environmental impact assessment of alternative fuel ...

Journal of Environmental Protection and Ecology 11, No 1, 1–6 (2010) Air pollution

Environmental impact assessment of alternative fuel use plans in urban buses of Thessaloniki A. Lioliosa, K. Nikolaoub* Alexander Technological Educational Institution of Thessaloniki, P. O. Box 141, 57 400 Thessaloniki, Greece E-mail: [email protected] b Organisation for the Master Plan and Environmental Protection of Thessaloniki, 105 Vas. Olgas Street, 54 643 Thessaloniki, Greece E-mail: [email protected] a

Abstract. The subject of the present study is the local as well as the total environmental impact of a future introduction of different types of alternative fuels in the urban buses system of Thessaloniki. Specifically, it is being studied to which extent do the emissions from the buses burden the atmosphere of Thessaloniki and the area around the city, and how could these emissions be reduced by the implementation of alternative fuels. From the present study the following general conclusions come out: the use of biodiesel at the buses of Thessaloniki has an advantage over diesel because it causes a relatively greater reduction of HC and CO2 emissions on a large scale, and CO, NOx and HC emissions on a local scale, whereas the use of natural gas predominated over diesel, because it causes a relatively greater reduction of NOx and particulate matter (PM) emissions on a large scale, and noise and particulates reduction on a local scale. Keywords: biodiesel, compressed natural gas (CNG), COPERT III method, urban transit buses, environmental assessment.

aims and background The contemporary diesel engine vehicles present very low power yield and simultaneously comprise one of the major air-polluting sources mainly with CO2 and particulate matter (PM). Directive 2003/30/EC of the European Parliament and of the Council of 8 May 2003 aims at promoting the use of biofuels or other renewable fuels to replace diesel or petrol for transport purposes in each member state, with a view to contributing to objectives such as meeting climate change commitments, environmentally friendly security of supply and promoting renewable energy sources1–3. The current work focuses on the study of the local as well as the total environmental impacts of a forthcoming introduction of different types of alternative fuels in the transit buses system of Thessaloniki. Specifically, it is being studied *

For correspondence.



to which extent do the emissions from the transit buses burden the atmosphere of Thessaloniki and of the area around the city, and how could these emissions be reduced by the application of biodiesel mixtures and natural gas. In Greece, an alternative automotive fuel is already being used. Since 2005, petrol diesel contains a small amount of biodiesel (4% v/v) and through legislation this amount will be gradually increased until 2010 (Ref. 2). experimental In this study, three 12-year projection time scenarios were configured, which involve the introduction of diesel alternatives into the bus fleet of Thessaloniki. The first scenario anticipates the switch from B4 (biodiesel 4%) mixture to B12 (biodiesel 12%) after 2009, the second one the switch from B4 to B20 (biodiesel 20%), also after 2009, and the third one – the gradual introduction of compressed natural gas (CNG) buses (the main fuel remains B4), again from 2009 forward. The theoretical calculations performed in this study, according to the COPERT III method, showed that in the year 2007 the buses of Thessaloniki will cover 45.3 mil. km, 63% of them inside the urban area and the rest 37% outside the bounds of the city. The same calculations also showed that the entire bus fleet will consume 22.26 mil. l of B4 mixture, and that the average consumption of each bus will be 0.491 l/km. Regarding the pollutants emissions, in 2007 there will be released in the atmosphere: – 227 t of CO – 676 t of NOx (nitrogen oxides) – 86.1 t of HC (hydrocarbons) – 30.8 t PM (particulate matter). From among the total amounts of these emissions, 75% of them will be released in the atmosphere of the city of Thessaloniki and the rest in the atmosphere of the surrounding regions. Also, from this total, 40% are being emitted from articulated buses, 58% from normal buses and 2% from mini-buses. Results and Discussion Figures 1, 2 and 3 present the projections of the legislated emission gasses, CO, NOx, PM and HC, for the 3 scenarios. These concern the implementation of 2 alternative fuels in the transit bus fleet of Thessaloniki.



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Fig. 3. Column plot of the total emissions per year for scenario 3 (CNG)



At the 1st scenario the B4 fuel is substituted by B12 fuel after the year 2009. This is assumed in order to conform to the European Commission directive 2003/30/ EC, which anticipates the usage of at least 5.75% (per volume) of bio-fuels from the total amount of fuels used for automotive transits. The conformation time limit of the directive is the year 2010. According to the standard bus replacement program (after they have completed 12 years of circulation), 103 ‘Euro 4’ new buses will be running by the year 2008. After that, all the other old buses are assumed to be substituted gradually by new ones of ‘Euro 5’ technology, by the year 2018. At the 2nd scenario everything is assumed to change as in the 1st scenario, but the alternative fuel will be B20. Finally, at the 3rd scenario the main fuel is B4, but it is assumed that pass the year 2009 every new bus will be of CNG technology. From these 3 scenarios these results can be deduced: 1. The contemporary buses of Euro 4 and Euro 5 are highly low-polluting. In the scenarios that concern biodiesel mixtures higher than 4%, the emissions reduction is radical. So, in scenarios 1 and 2 the CO, PM and HC emissions are reduced during the 12 years duration. More specifically: – CO emissions are cut down by 92.1 and 92.5% in scenarios 1 and 2, respectively; – PM is reduced by 94.2% in the 1st scenario and 94.5% in the 2nd scenario; – HCs are reduced by 95.1% in the 1st scenario and 95.5% in the 2nd scenario. These reductions constitute a highly ideal situation, since the emission factors used for the calculations were taken from the construction factory. Driving the specific buses under real conditions could alter these numbers. So, it is specified that these calculations contain a high degree of uncertainty. 2. Compressed natural gas exhibits low CO and PM emissions but it is well known that it promotes hydrocarbons emissions. The 3rd scenario showed for the year 2018, a 96% increase of the HCs compared to the year 2007. For this increase, most responsible is the CH4 and not the rest of the non-methane hydrocarbons (NMHCs), which are responsible for the photochemical fog. From the 3rd scenario the following emissions reduction come out, during the period 2007–2018: – CO 89.7% – NOx 50% and – PM 96%. 3. CNG buses, when operated, produce less noise. Various European studies have shown that the use of this type of buses produces up to 14% less external noise4. 4. Carbon dioxide (CO2) comprises the major factor of the green house effect. The use of biodiesel is beneficial for the CO2 emissions in the atmosphere, since 

the life cycle of this fuel shows very little total emissions. More specifically, the life cycle analysis (LCA) on heavy type vehicles shows a 13% reduction of the CO2 emissions for the CNG and a 56–72% reduction for the biodiesel5 (compared to diesel). 5. From a more general environmental aspect of view, total emissions of the rest of the legislated air pollutants (for the alternative fuels studied here), in comparison to diesel fuel, exhibit various fluctuations. In some cases, total emissions from alternative fuels overcome those of diesel. Specifically, for the biodiesel NOx increase by 18–27%, particulates decrease by 2–10%, CO emissions vary from –19% to +112% and hydrocarbons from –32% to +20%. Respectively, the LCA of the CNG (always compared to diesel) shows a 155–488% increase for the HC, a 0–430% increase for the CO, a 85% reduction for the PM and a 65–84% decrease for the NOx (Refs 2 and 6). 6. In general, biodiesel is a fuel more expensive than diesel. Although, when the production of the biodiesel (from the so-called energy plants) is localised and certain environmental taxation policy is followed, then the benefit is double. First of all, the final price of the product is reduced, since there is no need to import it and secondly, new working positions are being opened. But the energy plant crops demand vast land cultivation, so it is possible that other types of cultivations are suppressed1. 7. The biggest and most important air pollutant in the atmosphere of Thessaloniki is probably the particulate matter. Going through the 3 scenarios studied here, it comes out that the use of both biodiesel (12 or 20%) and CNG cuts down the PM emissions dramatically (by 94.2, 94.5 and 96% for the 3 scenarios, respectively). This could easily imply that both of these alternative fuels would be beneficial for the atmosphere of Thessaloniki, as far as particulate matter is concerned vehicles traffic is responsible for most of the quantities of the CO, NOx and NMHCs emissions. All 3 scenarios studied here foresee major reduction for all these pollutants. Conclusions The following 2 major conclusions can be drawn from the current study: – the use of biodiesel at the transit buses of Thessaloniki has the advantage of a relatively greater reduction on the total emissions of HC and CO2 in a greater atmospheric scale and on CO, NOx and HC in a local scale; – the use of natural gas has the advantage of a relatively greater reduction on the NOx and PM emissions in a greater atmospheric scale and on noise and PM in a local scale.



References 1. G. SAKELLAROPOULOS: Investigation of Alternative Fuel Sources and Technologies for the Improvement of the Energy and Environmental Behavior of the Public Transit System of Thessaloniki. Bus Transit Council of Thessaloniki, 2003. 2. G. SAKELLAROPOULOS: Investigation and Formulation of Proposal for the Usage of Natural Gas in the Urban Transit System of Thessaloniki. Final essay, Bus Transit Council of Thessaloniki, 2007. 3. 3rd National Assay for the Promotion of Usage of Biofuels or Other Renewable Fuels for the Transportation in Greece in Period 2005–2010. December 2006. 4. P. COROLLER, G. PLASSAT: Comparative Study on Exhaust Emissions from Diesel- and CNG-powered Urban Buses. In: Diesel Engine Emissions Reduction Conference, Newport, Rhode Island, 2003. 5. International Energy Agency, Automotive Fuels for the Future: The Search for Alternatives, IEA AFIS & IEA-AMF, 1999. 6. EPA: A Comprehensive Analysis of Biodiesel Impacts on Exhaust Emissions – Draft Technical Report, Assessment and Standards Division Office of Transportation and Air Quality, U.S. Environmental Protection Agency, 2002. Received 10 June 2008 Revised 11 July 2008



Journal of Environmental Protection and Ecology 11, No 1, 7–19 (2010) Water pollution

Decolourisation ofazo dyes containing wastewater by Phanerochaete chrysosporium in a rotating biological contactor G. Demir Faculty of Engineering, Department of Environmental Engineering, Bahcesehir University, 34 349 Besiktas, Istanbul, Turkey E-mail: [email protected] Abstract. In this study, removal efficiencies of colour, COD, copper and aromatics in different concentrations of Remazol Yellow RR gran, Remazol Red RR gran and Remazol Blue RR gran were analysed using white rot fungus, namely Phanerochaete chrysosporium. Colour and COD removal efficiency values were compared with respect to EN ISO 7887 standards and Turkish water pollution and control legislation limit values. Colour measurements were made using values of the index of transparency parameter. Values of index of transparency = DFZ (DurchsichtsFarbZahl), in accordance with the EN ISO 7887 standards, were obtained by taking absorbance in 436, 525 and 620 nm. DFZ values were calculated from these measurements. The reactor hydraulic retention time was kept at 4 days (1ml/min of continuous flow rate) and 2 days (2 ml/min of continuous flow rate) with a 10 mg l–1 concentration of Remazol mixture and the disc rotating speeds were 10 and 15 rpms. The optimum reactor hydraulic retention time was determined to be 4 days. After the determination, experiments were carried out at the dye concentrations of 5, 10, 15, 20, 25 mg l–1 and disc rotation speeds of 5, 10, 15 rpms. As a result, disc rotation speed and removable dye concentration were determined to be 10 rpm and 10 mg l–1, according to the EN ISO 7887 standards for Remazol mixture and the specific type of reactor used. Keywords: textile wastewater, azo dyes, biodegradation, Phanerochaete chrysosporium, rotating biological contactor, decolourisation.

aims and background When coloured wastewater is discharged directly to the environment, the already toxic dyes cause the formation of more toxic wastes, especially in anaerobic conditions and this creates significant environmental problems1. Nowadays, the most common and standard treatment applied to textile wastewater involves biological and chemical methods2. Dyes can not be reduced to CO2 by adsorption, but instead pass from liquid phase to solid phase. Degradation of dyes can only be realised by chemical or biological oxidation. Since synthetic dyes are resistive to biological degradation, colour removal by biological processes is difficult. Colour removal is generally realised by adsorption of dyes on bacteria rather than oxidation in aerobic systems. Literature has shown that some of the anaerobic microorganisms degrade dyes by reducing their nitrogen bonds, but toxic and carcinogenic 

compounds might be formed as final products as a result of the biological degradation3,4. Nevertheless, colour can be regained through contact of anaerobic degradation products with oxygen5. Using bacteria, these problems restrict the colour removal in large amounts. Because of the above-explained problems, faced with active sludge systems or aerobic, anaerobic bacteria during colour removal, colour and organic load removal with white rot fungi was studied in this study. It has been shown that white rot fungus has the ability to degrade many substances which are difficult to degrade, such as lignin, chlorinated aromatic and aliphatic hydrocarbons, and dyes by using extracellular enzyme systems1,6. The most commonly used white rot fungus types are Phanerochaete chrysosporium, Coriolus versicolor and Trametes versicolor. White rot fungus has a more active biological degradation in nutrition media where nitrogen is limited7–9. For this reason, by using a nitrogen-limited nutrition media in the study, the goal has been to make the white rot fungus take the nitrogen necessary for their microbiological activities from the nitrogen existing in the structure of the azo dyes. In the existing literature, there have been studies related to colour removal with white rot fungus in wastewater containing only one dye8,10,11. From this point of view, in this study, colour, COD, aromatic group and Cu removal using one of the white rot fungi has been investigated. The white rot fungi used was Phanerochaete chrysosporium, in a model wastewater containing certain concentrations and mixtures of Remazol Blue RR gran, Remazol Red RR gran and Remazol Yellow RR gran, which have been produced by the Dyster company and are of the widely used azo dyes because they are new. The obtained biological degradation efficiencies were compared with limit values in the legal regulations12,13. During colour measurements, a new colour parameter called Index of transparency parameter (DFZ = DurchsichtsFarbZahl) was used in accordance with the European Norm EN ISO 7887 (Refs 14 and 15). COD values were interpreted with respect to Water Pollution Control Legislation discharge limit values. As a result, in case of Remazol Yellow RR gran, Remazol Red RR gran, Remazol Blue RR gran, which have wide range of utilisation areas in the textile sector, exist in aquatic environments separately or together. The treatability of the colour and pollution load by one of the white rot fungi Phanerochaete chrysosporium, has been investigated. experimental Material and Methods

Microorganism. Phanerochaete chrysosporium ME 466 was first isolated by forest products laboratory in USA (Ref. 16). 

Cultivation conditions. Cultivation conditions of Phanerochaete chrysosporium culture were performed according to the method used by Demir12. Decolourisation medium. In the studies, the medium suggested by Zang et al.17 was used as basic nutrition medium. Nutrition medium components, which existed in very small amounts, were initially prepared as stock solutions. Later, the abovestated amounts were used from these stock solutions. The same procedure was also followed while adding the dyes. Azo dyes. Three Remazol group dyes, namely; Remazol Yellow RR gran, Remazol Red RR gran and Remazol Blue RR gran, produced by Dystar company were used both separately and together in order to analyse the colour removal efficiency. Reactor. The reactor was used in all the experiments designed for this study. The system can be seen in Fig. 1 (Ref. 12).

Fig. 1. Schematic diagram of operating system: 1 – entering water tank; 2 – exiting water tank; 3 – biodisc unit; 4 – peristaltic pump; 5 – heater with thermostat; 6 – electrical motor; 7 – air filter; 8 – flowmeter; 9 – air compressor; 10 – control panel

Sterilisation and colonisation. The reactor was filled with 70% methanol for sterilisation up to the working volume before being commissioned12,18. In order to see the biological adsorption effect of the dyes on the fungi, distilled water containing the same concentration of dye and fungi, but without nutrition substance, was used to make checks in the batch reactor and was incubated at the same conditions with the biological degradation experiments18. Analytical Methods

Colour measurements. In the studies, DFZ parameter was chosen in accordance with the standards determined by the European Norm EN ISO 7887. DFZ limit values



determined according to European norm, are 7 m–1 for 436 nm, 5 m–1 for 525 nm and 3 m–1 for 620 nm (Refs 13–15). DFZ calculation was made according to: DFZ= 100 (Eλ/d)

where Eλ is extinction (at a known wavelength), and d – the thickness of sample in cm. COD analysis. COD experiments were realised according to the standard method (open reflux, titrimetric method) stated in APHA 5220 B (Ref. 19). Aromatic group analysis. Aromatic group analyses were realised by using a Jenway type 6105 UV/visible spectrophotometer at 280 nm after the wastewater sample, which passed colour removal process, was passed from the processes stated in Section Colour Measurements20. Biomass measurement method. The formed biomass amounts were determined by making dry weight measurement experiments21,22. For the changes of biomass formed on the reactor disc surface, samples having a certain area (about 1cm2) were taken from the surface23. Metal analysis. In order to determine the removal ratio of copper existing in the structure of the Remazol Blue RR gran in 2%, an UNICAM 929 AA atomic adsorption equipment was used20. Results and Discussion Colour, COD and Aromatic Group Removal in Biodisc at Various Dye Concentrations

First of all, the optimum hydraulic retention time was determined for the biodisc system by studying colour removal at different hydraulic retention times (hydraulic retention time 4 days = feed flow rate 1ml/min, hydraulic retention time 2 days = feed flow rate 2 ml/min) using the treatable dye concentration of 10 mg l–1 (10 mg l–1 R. mixture, 10 mg l–1 R. Yellow, 10 mg l–1 R. Red, 10 mg l–1 R. Blue), which was determined for batch system13. Using the model wastewater of 10 mg l–1 R. mixture when the reactor hydraulic retention time was kept at 4 days (1 ml/min) and disc rotation speed was kept at 10 rpm, it has been observed that all dyes provided the required EN ISO 7887 discharge limit values (λ(1)= 436 nm (Yellow) 7 m–1, λ(2)= 525 nm (Red) 5 m–1, λ(3)= 620 nm (Blue) 3 m–1). After these values had been determined, colour removal efficiency of 10 mg l–1 1 R. mixture at hydraulic retention time 2 days (2 ml/min flow rate) and disc rotation speed at 10 rpm was determined. It can be seen that both R. Red and R. Yellow values are above the desired values of 5 and 7 m–1. It has been known that passage speed and amount of oxygen in water can be increased by increasing disc rotation speed in a surface ventilated reactor. From 10

suspended biomass amount in biodisc (mg/20 ml)

this point of view, hydraulic retention time was kept 2 days and disc rotation speed was increased to 15 rpm in order to see the effect on the removal efficiency. However, this modification did not have a significant positive effect on the treatment efficiency. Nevertheless, some breaks were observed due to the increase in the disc rotation speed. Limit discharge values required by EN ISO 7887 could not be attained at dye concentrations of 10 mg l–1 both for R. Red and R. Blue. The required limit discharge value (7 m–1) was attained for 10 mg l–1 of R. Yellow. Whenever the hydraulic retention time was kept at 4 days (1 ml/min flow rate), 200–300 mg l–1 of COD values required by Water Pollution and Control Legislation were attained with all dyes (10 mg l–1). However, when the hydraulic retention time was 2 days (2 ml/min), COD values were observed to be as high as 400–450 mg l–1 for all dyes (10 mg l–1). These results are above the Water Pollution and Control Legislation limit discharge values, which are 200–300 mg l–1. During the colour removal experiments, changes in suspended microorganism amount and the amount of biomass clinged to the disc surface were also observed. The suspended microorganism amount in the reactor initially dropped, then decreased for a while, but increased after a period. Since there were some breaks in the biofilm formed on the biodisc surface due to thickening, if the biofilm suspended, microorganism amount increased (Fig. 2). One of the most important characteristics of the white rot fungi is that they grow very well on the surfaces. Due to the substrate, the microorganism showed significant growth on the surface during the disc surface growth. Later, biofilm thickness reached to a certain amount and breaks were faced, and thus the biofilm thickness decreased (Fig. 3). This fact is supported by the information gathered from treatment of toluene in a reactor cultivated with petrochemical wastewater in a laboratory scaled biodisc system23. 3.5

R. Yellow R. Red R. mixture - 1 ml/min R. mixture - 2 ml/min R. Blue

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Fig. 3. Biomass changes on disc surface in removal of R. Yellow, R. Red, R. Blue and R. mixture dyes with biodisc system. Hydraulic retention time for R. Yellow, R.Red, R. Blue and R. mixture 4 days (feed volume flow rate 1ml/min); hydraulic retention time for R. mixture 2 days (feed volume flow rate 2ml/min); in all experiments ventilation flow rate 1.5 l/min, disc rotation speed 10 rpm, total dye feed concentration 10 mg l–1

During the experiments carried out with 10 mg l–1 R. mixture and 10 mg l–1 R. Blue, removal of copper consisting in the structure of the R. Blue dye was investigated at a hydraulic retention time of 4 days. 0.2 ppm of copper exists in 10 mg l–1 of Remazol Blue dye concentration. It has been determined that 39% of this copper could be removed during a process of 105 h. Up to the 45th hour, copper removal rate increased progressively. After that time, it has been observed that removal percentage decreased. The reason for this fact is that copper in the wastewater loaded to the reactor was tolerated by the microorganisms up to a certain time and used for conversion to the biomass. However, with a high concentration of 0.2 ppm for copper and a continuous flow rate of 1 ml/min, copper entering continuously to the system could not be totally transformed to biomass and also had some toxic effects. Aromatic group measurements were carried out in the UV region at 280 nm wavelength on the samples taken during the colour removal operations. As a result of the measurements, it has been revealed that there has been non-degraded aromatic group in the wastewater used for colour removal processes12. However, the Dystar company that supplied the dyes did not give any detail about the chemical composition of the dyes. For this reason, there could not be a clear conclusion about the type of the aromatic groups contained in the wastewater after the processes. After trial experiments carried out at 10 mg l–1 dye concentration using the biodisc, studies were continued with making trials at dye concentrations of 5, 15, 20 and 25 mg l–1 and at various disc rotation speeds (5, 10, 15 rpm). The obtained results are gathered in the Tables 1–6. Using the model wastewater of 5 mg l–1 R. mixture, when the reactor hydraulic retention time was kept at 4 days (1 ml/min) and disc rotation speed was kept at 5, 10 and 15 rpm, colour removal was observed (Table 1). It has been observed that all dyes provided the required EN ISO 7887 discharge limit values (λ(1)= 436nm (Yellow) 7 m–1, λ(2)= 525 nm (Red) 5 m–1, λ(3)= 620nm (Blue) 3 m–1). 12

Table 1. Colour removal values (DFZ m–1) of 5 mg l–1 of R. mixture dye at various disc rotation speeds

Time (h)  0 12 22 36 44 59 67 83 91 105 DFZ removal efficiency (%)

5 rpm 10 rpm 15 rpm R. Y. R. R. R. B. R. Y. R. R. R. B. R. Y. R. R. R. B. 4.9 5 1.5 4.9 5 1.4 5 4.9 1.5 2.5 3.2 0.9 2.1 2.5 0.8 3 3 0.8 2.6 3.3 0.5 2 3 0.6 2.9 3.1 0.7 2.5 3.2 0.7 2 3 0.6 3 3.1 0.7 2.6 3.4 0.9 2.1 3.1 0.7 2.8 3 0.8 2.5 3 1 2.2 3.1 0.7 2.8 3.2 1 2.7 3.4 0.9 2 3 0.7 2.6 3.3 0.8 2.6 3.4 1 2.1 3.1 0.6 2.8 3.2 0.9 2.6 3.2 0.9 2.2 3 0.7 2.9 3.2 1 2.6 3.2 0.9 2.2 3 0.6 2.9 3.2 1 46 36 40 55 40 57 42 35 33

EN ISO 7887 discharge limit values (λ(1)= 436 nm (Yellow) 7 m–1, λ(2)= 525 nm (Red) 5 m–1, λ(3) = 620 nm (Blue) 3 m–1).

Using the model wastewater of 10 mg l–1 R. mixture when the reactor hydraulic retention time was kept at 4 days (1 ml/min continuous flow rate) and disc rotation speed was kept at 5, 10 and 15 rpm, colour removal was observed. As it can be seen in Table 2, R. Yellow has given 4.8 DFZ exit value from 9.2 DFZ start value at a disc rotation speed of 5 rpm. With this value, 48% of DFZ removal efficiency was obtained. This DFZ value provides standard discharge value, which is 7 m–1. R. Red has given a DFZ value of 5.2 m–1 after an initial DFZ value of 9 m–1. This has resulted in a removal efficiency of 42%. This DFZ value, however, does not provide standard discharge value. R. Blue has given a DFZ value of 1.9 m–1 after an initial DFZ value of 2.4 m–1. This has resulted in a removal efficiency of 21% and correspondingly provided the standard discharge value of 3 m–1 (Table 2). In the experiments carried out using 10 mg l–1 R. mixture model wastewater at disc rotation speed of 10 rpm, DFZ value of R. Yellow decreased from its initial value of 9 m–1 down to 4.2 m–1. 53% of removal efficiency has been obtained from this value. It has been observed that reactor exit DFZ value has provided the discharge standard value, which is 7 m–1. DFZ value of R. Red decreased from its initial value of 9 m–1 down to 4.8 m–1. 47% of removal efficiency has been obtained from this value. Besides, it has been observed that reactor exit DFZ value has provided the discharge standard value, which is 5 m–1. DFZ value of R. Blue decreased from its initial value of 2.3 m–1 down to 1.6 m–1. 30% of removal efficiency has been obtained from this value and it has been observed that reactor exit DFZ value has provided the discharge standard value that is 3 m–1 (Table 2). 13

Table 2. Colour removal values (DFZ m–1) of 10 mg l–1 of R. mixture dye at various disc rotation speeds

Time (h) 0 12 22 36 44 59 67 83 91 105 DFZ removal efficiency (%)

5 rpm 10 rpm 15 rpm R. Y. R. R. R. B. R. Y. R. R. R. B. R. Y. R. R. R. B. 9.2 9 2.4 9 9 2.3 9.1 9 2.4 5 5.5 1.9 4.3 4.5 1.6 5 5.2 2 4.8 5.2 1.8 4.8 4.7 1.5 4.5 5.1 1.7 5 5.3 1.8 5 5 1.5 4.6 5.3 1.6 4.5 5 1.7 4.3 4.8 1.5 4.6 5.2 1.6 4.5 5.1 1.8 4.8 4.8 1.7 4.7 5.2 1.7 5 5 1.8 4.7 4.9 1.7 4.8 5.2 1.8 4.9 5.2 1.9 4.5 4 1.6 4.2 5.2 1.7 4.8 5 1.8 4.5 4.9 1.6 4.8 5.3 1.6 4.8 5.2 1.9 4.2 4.8 1.6 4.8 5.2 1.7 48 42 21 53 47 30 47 42 29

EN ISO 7887 discharge limit values (λ(1) = 436 nm (Yellow) 7 m–1, λ(2)= 525 nm (Red) 5 m–1, λ(3) = 620 nm (Blue) 3 m–1).

In the experiments carried out using 10 mg l–1 R. mixture model wastewater at disc rotation speed of 15 rpm, DFZ value of R. Yellow decreased from its initial value of 9.1 m–1 down to 4.8 m–1. 47% of removal efficiency has been obtained from this value. It has been observed that reactor exit DFZ value has provided the discharge standard value that is 7 m–1. DFZ value of R. Red decreased from its initial value of 9 m–1 down to 5.2 m–1. It has been calculated that 42% of removal efficiency could be obtained from this value. It has been observed that reactor exit DFZ value did not provide the discharge standard value, which is 5 m–1. DFZ value of R. Blue decreased from its initial value of 2.4 m–1 down to 1.7 m–1. It has been calculated that 29% of removal efficiency could be obtained from this value. Reactor exit DFZ value has provided the discharge standard value, which is 3 m–1 (Table 2). DFZ removal values of 15 mg l–1 of R. mixture dye can be seen in Table 3. It has been observed that R. Yellow has provided the EN ISO 7887 standard value of 7 m–1 with its DFZ values 6.3, 5.7 and 6.9 m–1 at disc rotation speeds of 5, 10 and 15 rpm, respectively. One of the other dyes constituting the mixture, namely R. Blue, provided the standard value of 3 m–1 while R. Red did not provide the standard value of 5 m–1. DFZ removal values of 20 mg l–1 of R. mixture can be seen in Table 4. It has been observed that R. Yellow, which is one of the dyes in the mixture, provided the standard 7 m–1 value of EN ISO 7887 at disc rotation speeds of 5 and 10 rpm with DFZ resulting values of 6.8 and 6.5 m–1, respectively, while it did not provide the standard value at 15 rpm with resulting DFZ value of 7.5 m–1. One of the other 14

dyes constituting the mixture, namely R. Blue, provided the standard 3 m–1 value of EN ISO 7887 at disc rotation speeds of 5 and 10 rpm with DFZ resulting values of 2.6 and 2.4 m–1, respectively, while it did not provide the standard value at 15 rpm with resulting DFZ value of 3.2 m–1. On the other hand, all DFZ values of R. Red were above the standard value of 5 m–1. Table 3. Colour removal values (DFZ m–1) of 15 mg l–1 of R. mixture dye at various disc rotation speeds

Time (h) 0 12 22 36 44 59 67 83 91 105 DFZ removal efficiency (%)

5 rpm 10 rpm 15 rpm R. Y. R. R. R. B. R. Y. R. R. R. B. R. Y. R. R. R. B. 14 13 3 14 13 3 14 13 2.9 6.5 8 2.1 7 7 2 8 8 2.4 6.6 7 2 6.5 6.8 1.9 7 7.8 2.3 6.3 7 2.2 6 6.8 1.8 7.1 7.3 2.2 6.2 7.2 2 5.5 7 1.7 7 7.5 2.4 6 7.3 2 5.6 7.1 1.6 6.9 7.5 2.4 6 7.3 2.2 5.8 7 1.6 6.9 7.6 2.3 6.1 7.2 2.2 5.8 7.1 1.6 6.8 7.4 2.2 6.3 7.1 2.3 5.7 7 1.7 7 7.5 2.3 6.3 7.1 2.2 5.7 6.8 1.7 6.9 7.5 2.4 55 45 27 59 47 43 51 42 17

EN ISO 7887 discharge limit values (λ(1) = 436 nm (Yellow) 7 m–1, λ(2) = 525 nm (Red) 5 m–1, λ(3) = 620 nm (Blue) 3 m–1). Table 4. Colour removal values (DFZ m–1) of 20 mg l–1 of R. mixture dye at various disc rotation speeds

Time (h)  0 12 22 36 44 59 67 83 91 105 DFZ removal efficiency (%)

5 rpm 10 rpm 15 rpm R. Y. R. R. R. B. R. Y. R. R. R. B. R. Y. R. R. R. B. 17 17 4.4 17 17 4.3 17 17 4.3 6.8 10 2.4 9 8.6 2.4 10 11 3.3 6.5 8.1 2.5 6.5 7.5 2.1 9 9 3 6.5 8.2 2.5 6.4 7.8 2 7.5 8.4 3 6.8 7.9 2.4 6.5 7.8 2.2 7.7 8 3.1 6.7 7.8 2.6 6.5 7.6 2 7.6 7.9 3.3 6.8 7.4 2.6 6.6 7.6 2.3 7.4 7.6 3.2 6.8 7.4 2.6 6.3 7.7 2.4 7.5 7.5 3.2 6.7 7.5 2.7 6.2 7.6 2.3 7.5 7.9 3.2 6.8 7.4 2.6 6.5 7.7 2.4 7.5 7.9 3.2 60 56 41 61 54 44 56 54 26

EN ISO 7887 discharge limit values (λ(1) = 436 nm (Yellow) 7 m–1, λ(2) = 525 nm (Red) 5 m–1, λ(3) = 620 nm (Blue) 3 m–1).

15

Table 5 shows that all DFZ values of all dyes constituting 25 mg l–1 or R. mixture were above the standard values determined by EN ISO 7887. Table 5. Colour removal values (DFZ m–1) of 25 mg l–1 of R. mixture dye at various disc rotation speeds

Time (h) 0 12 22 36 44 59 67 83 91 105 DFZ removal efficiency (%)

R. Y. 20 12 11.5 11 12 12 12 12.1 12.1 12 40

5 rpm R. R. R. B. 21 5.4 14 4.8 14 4.3 13.1 4.2 16 4.3 15 4.5 14.8 4.7 14.8 4.6 14.7 4.3 14.5 4.5 31 22

R. Y. 20 11 11 11.5 12 11 11.1 11.2 11.1 11.2 44

10 rpm R. R. R. B. 21 5.4 13 4.3 13.5 4.1 13.5 4 14 4.6 14 4.3 14.3 4 14.3 4.1 14 4 13.8 4.2 34 17

R. Y. 20 13 13.2 13 13 12.5 12.7 14 14.2 14.3 29

15 rpm R. R. R. B. 20 5.3 14.2 4.6 14.1 4.3 13.9 4.3 13.5 4.4 13.5 4.6 14 4.6 14.6 4.7 14.5 4.7 14.7 4.6 27 13

EN ISO 7887 discharge limit values (λ (1)= 436 nm (Yellow) 7 m–1, λ(2) = 525 nm (Red) 5 m–1, λ(3) = 620 nm (Blue) 3 m–1).

Table 6 shows the DFZ removal efficiencies corresponding to the first 12 h after the loading which was done after the reactor reached the steady state. The removal efficiencies for R. Yellow, R. Red and R. Blue obtained for disc rotation speed of 5 rpm were 46, 39 and 21%, respectively, for 10 rpm – 52, 50 and 30% and for 15 rpm – 45, 42 and 17%. Table 6. Colour removal (DFZ m–1) of 10 mg l–1 R. mixture dye during the first 12 h at various disc rotation speeds

Time (h) 0 2 4 6 8 10 12 DFZ removal efficiency (%)

5 rpm 10 rpm 15 rpm R. Y. R. R. R. B. R. Y. R. R. R. B. R. Y. R. R. R. B. 9.2 9 2.4 9 9 2.3 9.1 9 2.4 8 8 2.2 7.5 7.6 2 8 8 2.2 6.8 7.5 2.1 6.7 7 1.8 7.3 7.5 2 6 7 2 5.8 6.5 1.6 5.5 7 1.9 5.5 6.5 2 5.3 5.3 1.5 5.2 6 1.9 5.3 6 1.9 5 5S 1.4 5 5 2 5 5.5 1.9 4.3 4.5 1.6 5 5.2 2 46 39 21 52 50 30 45 42 17

EN ISO 7887 discharge limit values (λ(1) = 436 nm (Yellow) 7 m–1, λ(2)= 525 nm (Red) 5 m–1, λ(3) = 620 nm (Blue) 3 m–1).

16

It can be observed that the resulting COD values provided the required discharge limit of 200–300 mg l–1 for all disc rotation speeds after 44–59th hours after the system was run continuously (1 ml/min continuous flow rate) at dye concentrations of 5, 10 and 15 mg l–1, when the COD removal values of R. mixture dyes are compared with the limit discharge values of Water Pollution and Control Legislation. For dye concentrations of 20 and 25 mg l–1, however, the limit discharge values of 200–300 mg l–1 were exceeded. It has been known that heavy metals affect the cellular enzymatic reactions positively or negatively. If the concentration is low, the living thing can tolerate this and even use it for metabolic activities, but causes death if it is high. For this reason, the removal of copper existing at 2% in the structure of R. Blue RR gran by fungi during the experiments carried out in the biodisc. For the R. mixtures of 5 mg l–1 (0.012 ppm copper), 10 mg l–1 (0.024 ppm copper), 15 mg l–1 (0.036 ppm copper), 20 mg l–1 (0.048 ppm copper) and 25 mg l–1 (0.06 ppm copper) the arithmetic average of the copper removal values at 5, 10 and 15 rpm are 97, 90, 73, 51 and 48%, respectively. It has been determined that toxicity showed effect or at least microbial activities were slowed down with increasing concentration. Conclusions For dye concentrations of 10 mg l–1, which was determined for batch reactors, both separate and mixture of the Remazol dyes were used for the experiments with the biodisc system initially. Discharge standards were attained for 10 mg l–1 of R. Yellow according to the EN ISO 7887 at hydraulic retention time of 4 days, disc rotation speed of 10 rpm, but could not be attained for the dyes R. Red and R. Blue. When the hydraulic retention time was 4 days and the disc rotation speed was 10 rpm, all dyes provided the discharge limit values of EN ISO 7887 at 10 mg l–1 R. mixture. When the hydraulic retention time of 10 mg l–1 of R. mixture was kept at 2 days (2 ml/min flow rate) and disc rotation speed at 10 rpm, both Remazol Red and R. Yellow have been observed to be above the required limit discharge values when colour removal efficiencies have been analysed. When the results of the experiments at different disc rotation speeds were analysed, it has been observed that increasing the disc rotation speed to 15 rpm decreased the colour removal efficiency. It has been determined that this decrease was due to the breaks from the biofilm. For this reason, it has been revealed that disc rotation speed of 10 rpm is the proper one for a pilot reactor used in the studies. All values were observed to be above the standards for R. mixture concentration of 25 mg l–1 using the biodisc. During colour removal processes, aromatic group measurements were taken in UV region at 280 nm wavelength for experiments carried out both in batch re17

actors and on biodisc. As a result of these measurements, it has been revealed that there was non-degraded aromatic group in the model wastewater used for colour removal experiments at the end of the process. This fact is supported by other literature studies20. The great portion of the COD of the wastewater is composed of glucose, which is used to prepare the wastewater, and is a component of the nutrition media. For this reason COD removal has been realised by the white rot fungi rapidly. This fact is supported by the other literature results24. References  1. K. I. Kapdan, F. Kargi, G. Mcmullan, R. Marchant: Comparison of White Rot Fungi Cultures for Decolorization of Textile Dyestuffs. Bioprocess Engineering, 22, 347 (2000a).   2. I. A. Balcioglu, I. Arslan: Treatability of Textile Industry Wastewater by Photocatalytic Oxidation Method. Gebze Institute of Technology, Environmental Pollution Symposium, Vol. 2, Turkey, 1997, 193–199.   3. M. A. Brown, S. C. Devito: Predicting Azo Dye Toxicity. Critical Reviews in Environmental Sciences and Technology, 23, 249 (1993).   4. K. T. Chung, S. J. R. Stevens: Decolorization of Azo Dyes by Environmental Microorganism and Helmiths. Environmental Toxicology Chemistry, 12, 2121 (1993).   5. J. S. Knapp, P. S. Newby: The Microbiological Decolorization of an Industrial Effluent Containing a Diazo-linked Chromophore. Water Research, 29, 1807 (1995).   6. J. A. Bumpus, S. D. Aust: Studies on the Biodegradation of Organopollutants by a White Rot Fungus. In: Intern. Conference on New Frontiers for Hazardous Waste Management, 1985, 404–410.   7. D. C. Eaton: Mineralization of Polychlorinated Biphenyls by Phanerochaete chrysosporium – a Lignolytic Fungus. Enzyme Microbial Technology, 7, 194 (1985).   8. F. Zhang, J. T. Yu: Decolorization of Acid Violet 7 with Complex Pellets of White Rot Fungus and Activated Carbon. Bioprocess Engineering, 23, 195 (2000).   9. F. Zhang, J. S. Knapp, K. N. Tapley: Decolorization of Cotton Bleaching Effluent in a Continuous Fluidized Bed Bioreactor Using Wood Rotting Fungus. Biotechnology Letters, 20 (8), 717 (1999b). 10. K. I. Kapdan, F. Kargi: Biological Decolorization of Textile Dyestuff Containing Wastewater by Coriolus versicolor in Rotating Biological Contactor. Enzyme and Microbial Technoloy, 30, 195 (2001). 11. F. C. Yang, J. T. Yu: Development of a Bioreactor System Using an Immobilized White Rot Fungus for Decolorization. Bioprocess Engineering, 16, 9 (1996). 12. G. Demir: Decolorization of Textile Wastewaters Containing Azo Dyes by White Rot Fungus (Phanerochaete chrysosporium). Ph. D. Thesis, Istanbul University, Institute of Science and Technology, Department of Environmental Engineering, 2002. 13. G. Demir, M. Borat, C. Bayat: Decolorization of Remazol Red RR Gran by the White Rot Fungus Phanerochaete chrysosporium. Fresenius Environmental Bulletin, 13 (10), 979 (2004). 14. Europa Norm. 1994. EN ISO 7887. 15. T. Akgun: Color Removal from the Textile Wastewater by Adsorption Techniques. Msc Thesis, Istanbul University, Institute of Science and Technology, 1999. 16. G. R. J. Mileski, J. A. Bumpus, M. A. Jurek, S. D. Aust: Biodegradation of Pentachlor­ phenol by the White Rot Fungus Phanerochaete chrysosporium. Applied and Environmental Microbiology, 54, 2885 (1988).

18

17. F. Zhang, J. S. Knapp, K. N. Tapley: Decolourisation of Cotton Bleaching Effluent with Wood Rotting Fungus. Water Research, 33, 919 (1999a). 18. K. I. Kapdan, F. Kargi, G. Mcmullan, R. Marchant: Effect of Environmental Conditions on Biological Decolorization of Textile Dyestuff by C. versicolor. Enzyme and Microbial. Technology, 26, 381 (2000b). 19. Apha-Awwa-Wpcf: Standard Methods for the Examination of Water and Wastewater. 17th ed. New York, 1989. 20. A. Heinfiling, M. Bergbauer, U. Szewzyk: Biodegradation of Azo and Phthaloccynine Dyes by Trametes versicolor and Bjerkandera adusta. Applied Microbiology Biotechnology, 48, 261 (1997). 21. G. Demir: Degradation of Some Chlorinated Organic Materials by White Rot Fungus (Phanerochaete chrysosporium) in Waters. Msc Thesis, Istanbul University, Institute of Science and Technology, Department of Environmental Engineering, 1996. 22. G. Demir, H. Barlas, C. Bayat: Degradation of Some Chlorinated Organic Materials by White Rot Fungus (Phanerochaete chrysosporium) in Waters. Fresenius Environmental Bulletin, 7, 927 (1998). 23. I. Alemzadeh, M. Vossoughi: Biodegradation of Toluene by an Attached Biofilm in a Rotating Biological Contactor. Process Biochemistry, 36, 707 (2001). 24. H. Cao: Decolorization of Textile Dyes by White Rot Fungi. Ph.D. Thesis, University of Georgia, Faculty of Graduate, USA, 2000. Received 29 May 2009 Revised 1 July 2009

19

Journal of Environmental Protection and Ecology 11, No 1, 20–26 (2010) Water pollution

Constructive solutions regarding the purification of used water coming from the beer industry L. Calin*, M. Jadaneant Politehnica University of Timisoara, 1 M. Viteazu Street, 300 223 Timisoara, Romania E-mail: [email protected]; [email protected] Abstract. This work presents the necessity to implement integrated systems for purifying used water as a result of the evaluation of the surface waters quality in our country, especially of the wastewaters from beer breweries. The authors propose a modular system with a central work unit that controls, on the basis of some programmed algorithms, all the electromechanic equipments connected. In essence, the proposed system for purifying used waters in beer breweries consists of an anaerobe pre-treating combined with an aerobe post-treating. The work begins with some considerations concerning the quality of the surface waters: the indicators of the used waters, the composition of the wastewater in beer breweries, methods to purify the used waters. Then it is presented the functional-constructive and technological scheme of the installation and, finally, the efficiency of the mechanical-biological method of treating of the used waters from beer breweries. Keywords: used waters, purifying, decantation, neutralisation, purification efficiency.

GENERAL MATTERS REGARDING THE QUALITY OF SURFACE WATERS Referring to the new conditions imposed by the EU and, of course, the increasing interest regarding the normal maintenances and exploit of the natural resources in our country it has been noticed a more and more intense preoccupation in conserving and development of the existing resources. Wastewaters contain different substances and all kinds of pathogen bacteria that represent an important source of contamination, so a serious danger threat for the public health1. Wastewater must be evacuated downstream of human settings, in natural ponds with the condition of maintaining the water cleanness necessary for the public health, fishing ponds and last but not least the specification of the existing microclimate. The infiltration of used waters in the soil may lead to the contamination of subterranean waters, making them improper for household water supply. *

For correspondence.

20

Direct dumping in water streams is modifying the natural way of streaming, damaging the quality of the water by increasing its turbulence, changes of chemical composition, ruining the tourist landscape, reducing the amount of oxygen in the water, inducing huge ecological hazards, so using this water as a source for supplying houses, irrigations or pools is impossible. The wastewaters produce awful smelling gases, and with the high content of pathogen germs these waters are an important source in the process of spreading disease2. Wastewater indicators. The overloading with pollution of used waters is accounted in an equivalent of inhabitants (e. i.) and it is calculated referring to the maximum average weekly load of BOD5 that has entered the wastewater cleaning station in the course of a year, except situations of unexpected phenomenon, like torrential rains. The main indicators analysed for establishing the level of overload of the used water and the appointed level of purification of used waters are: • TSS (total suspended solids) – gels within the used water, are less of sediment than the organic material and they precipitate in time in the decantation pools in the form of mud; • BOD (biological oxygen demand) – the biochemical consumption of oxygen represents an indicator of water pollution with biochemical substances; • COD (chemical oxygen demand) – the chemical consumption of oxygen represents an indicator of water pollution with oxidable organic substances. Composition of dump waters that result from the beer industry. Water that results from the beer industry represents a perfect environment for the growth of microorganisms that produce different organic acids and then they make this water to rot3. Used waters from the beer industry contain: • water for cleaning and moisture of barley; it contains sugars, proteins, salts, and other impurities; • cleaning water – used for cleaning the production spaces and the process machines; • cooling and condensation water, draffy and mash from the beer; • the used brewery mash and the used beer yeast that occasionally end up in the wastewater; • bases and acids from the washing up substances of different machinery, which used organic material; • polyphenols used with the alkaline water from the polyvinylpropylene (PVPP) filter, kieselguhr which appears after filtering; • insoluble material (paper labels); • glue from the bottle labels, oil and lubricants used in the factory. 21

Methods for used water purification. Used water purification is a sum of all methods which are causing the reduction under the imposed limit by the emissary of the mineral, organic, chemic and biologic impurity using with high efficiency different facilities to purify the used waters, and the waste product slit is worked under the dehydration, stabilisation and fermentation process3,4. The most common methods are: • mechanical method, • chemical-mechanical method, • biologic method. When a method and the appropriate facility are to be chosen for used water purification process, several criteria should be followed: • up-to-date regulations; • environmental protection regulations; • specific factors: – extension of the populated area, – expansion of the purifying station, – river edge protection, – surface, – main wind circulation, – surface properties, under-water levels, – nearby crops, – electrical energy and drinking water. For used waters with suspended particles over the maximum limit, and looking for a better mixing it is used the mechanical method. The mechanical method is also called implicit pre-purification: through the metal grills, un-sanding sieves, dislodges and the septic tanks are used to remove the big solid suspensions in the water; the method is a water flow unification, and the reduction concentration of the chemical compounds in the used water is done by collecting and separation tanks (suspension are reduced by 40–60% and the BOD5 – 25–40%). Biological purification of the used waters regards the reduction of the degradable substances using the microorganisms that live in the used waters (BOD5 reduction to 90–95% and 90–95% bacteria is removed). TECHNICAL SOLUTIONS The process that we want to present is based on the phenomenon according to which in certain conditions the anaerobe bacteria are capable to agglomerate in granular shape offering a good grip on the wall and a big biochemical attraction. The used water (Fig. 1) enters the pumping station and transfers it to the smooth grills where the solid particles are retained. The material then is transported in 22

the storage tanks (2), the solid particles witch can cause grinding of the facility inside the pipes or the electro-mechanical equipment are retained in the un-sander (4) and the diluted sand suspension is pumped to the sand separator5,6. The sand is dehydrated in the storage tanks and the used water without the solid particles and sand flows gravitationally to the first radial dislodger (5) where the dislodged material is removed through pumping into the slit storage tank (10). The used water obtained arrives into the buffering tank (6), then pre-acidity tank (7), where the unification of the flow and factor variations are made (pH is adjusted to the desired level through graduation of caustic soda or muriatic acid injected through 2 graduation systems connected to an automatic measurement system of pH, coordinated by microprocessor).

Fig. 1. Technological scheme of the used water purification facility 1 – used water pumping station, 2 – separation channel, 3 – water tank, 4 – un-sander, 5 – primary dislodger, 6 – buffer tank, 7 – conditioning tank, 8 – anaerobic reactor, 9 – after burner tank, 10 – overload slit tank, 11 – used water pumping station, 12 – gas flow meter, 13 – burner

After pH and nutrients adjustments (urea and phosphoric acid), the used pre-acidified water is pumped with a controlled flow into the reactor (8) that has 2 sections mounted on a cylindrical housing. The biogas collected from the first section generates a liquefied gas resulting in an internal circulation of the used water and silt. The effluent anaerobic treated from the reactor flows gravitationally into the after-burner tank (9), in this point it is mixed with the diluted active slit and main23

tained in the system without recirculation. The diluted methane is extracted and driven outside the facility, the waste organic matter and the sulphur compounds are oxidised to CO2 and sulphur-containing chemical substances. The treated effluent without the separation of the slit is unloaded at the treating line of the facility. Biogas collected from the gas separator is sent to the gas-meter (12) for deposition. An automated burning system (13) for biogas is used to burn the gas without odour. The overload of anaerobic slit is extracted periodically from the reactor with a reversible pump loaded into the train and sent to slit storage tank (10). The primary slit and the anaerobic one are stored, stabilised and grossed in the slit storage tank which is aired and lateron dehydrated in a centrifugal dislodge. The main advantages of the facility described above versus the conventional anaerobic facilities are: • higher efficiency in a reduced work space; • for slit anaerobic recirculation we do not need to have special conditions; • no need to have support material for the anaerobic bacteria immobilisation; • no energy consumption for the intermixing the matter in the IC reactor; • granular slit concentration is rather high; due to the methane specific effect of the granular slit a small quantity of anaerobic slit is produced; • the remaining anaerobic slit is very stable, permitting a total disinfection; • the IC reactor has a system to separate the water/gas/slit, corrosion resistant, different flows resistant, good quality of the used water, enhancing the life of the facility; • standard tank modules for dislodge process are compact and easy to install; • elimination of the unpleasant odours due to the attached reactor; • big tolerance of the large content of solid matter retained at the reactor entrance; • low cost for reactive neutralisation due to the automatic alkalinity recovery. MEASUREMENTS OF THE MAIN INDICATORS IN THE BEGA–TIMIs reservoir The measurements made during 2000–2006 had the main objective to monitor the main indicators of the surface waters in the Bega–Timis reservoir, and make assessment according to the environmental rules and find new future solutions to reduce pollution from the waters. In Figs 2–4 are presented the average values measured in the laboratory for the nutritive substances of surface waters according to Norm 1146–2002 updated with the modifications made on 25.11.2005, in the section Deta–Otelec (Refs 7 and 8). 24

concentration (mg N/l)

0.16 0.14 0.12

N–NO2

0.1 0.08

lower limit

0.06

upper limit

0.04 0.02 0 2000

2001

2002

2003

2004

2005

2006

year

Fig. 2. Average concentration levels for N–NO2 concentration (mg N/l)

6 5 4

N–NO3 lower limit upper limit

3 2 1 0 2000

2001

2002

2003

2004

2005

2006

year

concentration (mg N/l)

Fig. 3. Average concentration levels for N–NO3 7 6 5

N–NH4

4

lower limit

3

upper limit

2 1 0 2000

2001

2002

2003

2004

2005

2006

year

Fig. 4. Average concentrations levels for N–NH4

concentration O2 (mg O2/l)

Forward are presented measurements for oxygen made in laboratory according to Norm 1146–2002 updated on 25.01.2005, in the section Deta–Otelec (Figs 5 and 6). 8 7 6 5 4 3 2 1 0

O2 lower limit upper limit

2000

2001

2002

2003

2004

2005

2006

year

Fig. 5. Average concentration level for O2

25

concentration (mg O2/l)

12 10 8

BOD-5

6

lower limit upper limit

4 2 0

2000

2001

2002

2003

2004

2005

2006

year

Fig. 6. Average concentration level for BOD5

CONCLUSIONS 1. Reducing nitrate and nitrites to allowable values due to the removal of punctiform contaminations sources. 2. Perform this task according to the norms by the corporations that are involved in this area which was bench-marked. Removing/reducing the accidental contamination made by the human factor (houses, small farms, etc.), by the economical agents9. Applying these measures that reduced pollution on the surface waters levels made by the corporations in cause. 3. Also the oxygen (O2, BOD5) level are under control, but during a year one can observe big variations, it can not be said the same about the nitrate concentrations; all in one these factors with the modern technologies in our days are in a continuous diminution. From the study analysis presented in this paper, taking into account the development at global level correlated with the fundamental objective revealed by the environment protection laws regarding the durable development of the society a major conclusion is drawn that the integrated use water purification systems have a major impact on industry, agriculture, energy field, transportations and communications being indispensable for the environment balance, making the activity for preventing ecologic risks and damage a issue of strategic importance9. REFERENCES 1. 2. 3. 4.

R. Antoniu: Industrial Wastewater Treatment. Publisher Engineering, Bucharet, 1987. G. Burtica: Waste Treatment Technologies. Publisher Engineering, Timisoara, 2000. I. Mirel: Construction and Hydro Plants. Western Publishing, Timisoara, 2002. D. Robescu: Hydrodynamics Hydropneumatic Transmission Facilities and Water and Air Depollution. Publisher Engineering, Bucharest, 1982. 5. STAS 4162/1-/89: Primary Sedimentation Tanks. Design Prescriptions. 6. STAS 4162/2-/89: Secondary Sedimentation Tanks. Design Prescriptions. 7. NTPA 001/2002: Settings Regulatory Limits Pollutant Load of Industrial Wastewater and Natural City Release to Receptors. 8. NTPA 002/2002: Regulatory Conditions for Wastewater Discharge into the Sewer Networks of Localities and Directly Sewage Plants. 9. Law No 137/29.12.1995/ 17.02.2005 – Environmental Protection Law. Received 5 March 2008 Revised 21 April 2008

26

Journal of Environmental Protection and Ecology 11, No 1, 27–35 (2010) Soil pollution

Analytical investigation of some organic compounds from contaminated areas with petroleum products V. Iancu*, M. Mitrita, J. Petre, L. Cruceru National Research and Development Institute for Industrial Ecology (ECOIND), 90–92 Panduri Street, Sector 5, Bucharest, Romania E-mail: [email protected] Abstract. The role of soil within an ecosystem is to be an interface between air, surface water and underground water and also a zone of transit or accumulation for majority of organic and inorganic pollutants. Soil oil pollution represents a great environmental threat as it may contaminate the neighbourhood soils and surface and underground water. Contamination may occur anywhere during crude oil extraction and treatment, oil product transportation, storing and utilisation. The Romanian Environmental Legislation, according to Order 756/97 sets the normal values for petroleum products in soil below 100 mg/kg d.m., between 200–1000 mg/kg d.m. for alert levels and between 500–2000 mg/kg d.m. for intervention levels. The objectives of these analytical investigations were to assess the magnitude of pollution with petroleum hydrocarbons within oil field and the vertical and horizontal extent of soil contamination. The samples were collected in different locations throughout the Romanian oil fields and were analysed for mineral oil, BTEX compounds (benzene, toluene, methylbenzene and xylene) and PAHs (polycyclic arenic hydrocarbons) (11 compounds). Important differences of the organic level of pollution were observed as function of the position and depth of the soil samples investigated. The obtained values varied within the following ranges: from 25 to 1718 mg/kg for mineral oil, from 0.01 to 4.31 mg/kg for BTEX and from 0.01 to 8.43 mg/kg for PAHs. Keywords: soil, analytical investigation, petroleum products.

aims and background High toxicity and carcinogenic potential of some organic compounds are imposing analyses and monitoring of these pollutants from various water and soil categories, even if are present in traces. The role of soil within an ecosystem is to be an interface between air, surface water and underground water and also a zone of transit or accumulation for majority of organic and inorganic pollutants. Petroleum products are representing the most frequently category of pollutants founded both in water and in soil, the main sources of pollution being accidental spillages and discharges from industrial plants (oil extraction and treatment, refineries, storing and utilisation, gas stations) and transport vehicles. These types *

For correspondence.

27

of pollution are causing damages of agricultural soil, leisure areas, and beaches and are inducing bad taste and smell in water, putting in danger the life of aquatic or terrestrial organisms. For analyses of some organic compounds from soil and water were used analytical techniques like IR spectrometry1 or gas chromatography2,3 for mineral oil (TPH), high performance liquid chromatography4,5 or gas chromatography6 for determination of polycyclic arenic hydrocarbons (PAH) and gas chromatographic methods7,8 for benzene, toluene, ethylbenzene, xylene (BTEX). The Romanian environmental legislation, according to Order 756/97, sets the normal values for petroleum products in soil below 100 mg/kg d.m., between 200–1000 mg/kg d.m. for alert levels and between 500–2000 mg/kg d.m for intervention levels. For PAH Order 756 establishes the normal value in soil below 0.1 mg/kg d.m., the alert levels between 7.5–25 mg/kg d.m., and the intervention levels between 15–150 mg/kg d.m. Also, for BTEX the normal value range is between 0.01–0.05 mg/kg d.m., the alert limits are between 0.25–30 mg/kg d.m. and the intervention levels range is 0.5–100 mg/kg d.m. The analytical investigations objective was to assess the magnitude of pollution with TPH, BTEX and PAH within the Moinesti oil fields and the vertical and horizontall extent of soil contamination. ExPERIMENTAL The samples were collected in different locations throughout the Romanian oil fields and analysed for TPH, BTEX compounds and PAHs (11 compounds). The selection of optimal analytical method for soil samples depended mainly on the chemical structure of organic compounds and their concentration level. Determination of TPH from soil. For determination of TPH from soil it was used the IR spectrometric method. A primary processing was performed in case of granulation of the soil sample higher than 2 mm and pollutants were heterogeneously distributed. It consisted of removal of various objects (vegetation, glass, metals, etc.) followed by chemical drying. The operation of chemical drying was performed through contact of equal quantities of soil (15 g) and anhydrous sodium sulphate (15 g). The mixture was kept at cold temperature for 12–16 h and periodically mixed in order to avoid formation of agglomerates. Liquid–solid extraction was applied as separation method using carbon tetrachloride as extraction solvents for 20 g dried soil. Purification of the compounds was realised by adding 5 g of magnesium silicate (particle size 60–100 mesh) to each extract. The analyses of TPH were performed on a FTIR Spectrum BX II spectrometer Perkin Elmer, using natrium chloride cell with 0.3 cm optical length. The absorbance of organic extract obtained after the soil treatment was measured in range of 3100–2800 cm–1 for three wavelengths: ν1 = 2925 cm–1 (CH2 absorption band), 28

ν2 = 2958 cm–1 (CH3 absorption band) and ν3 = 3030 cm–1 (CH arenic absorption band). Determination of BTEX from soil. In order to analyse BTEX from soil it was applied a gas chromatographic method with a flame ionisation detector (FID) using a gas chromatograph Agillent 6890N. The soil samples (without drying) were extracted first with methanol and then with hexane, by shaking on a mechanical stirrer. The organic extract was washed with distilled water in a separatory funnel and then it was filtered on anhydrous sodium sulphate. For BTEX separation was used a HP-5 capillary column (30 m × 0.32 mm intern diameter × 0.25 µm film thickness). Operating parameters were as follows: career gas flow 1 ml/min, air flow 400 ml/min, hydrogen flow 35 ml/min, split/splitless injection, injection volume 1 μl. The carrier gas was helium (99.9999% purity). The temperature program that ensured an optimal separation was: injector 250oC, detector 275oC, and column 50oC (5 min); 3oC/min to 100oC, and 20oC/min to 225oC (5 min). Determination of PAH from soil. For the determination of PAH it was applied high performance liquid chromatographic method in reverse phase with UV detection. Soil samples (without drying) were subjected to solid–liquid extraction using acetone and petroleum ether by shaking on a mechanical stirrer. The organic extract was washed with distilled water in a separatory funnel for acetone and polar compounds removal and then it was filtered on anhydrium sodium sulphate. The extracts were concentrated by evaporation at low pressure using a rotary evaporator till 1 ml. Purification is realised by passing of extract through an aluminium oxide column and elution with petroleum ether and enrichment of residue with acetonitrile. From soil samples were analysed 11 PAH compounds (naphthalene, phenanthrene, antracene, fluoranthene, pyrene, chrysene, benzo(a)anthracene, benzo(b+k)fluoranthene, benzo(a)pyrene, benzo(g,h,i)perylene, indeno(1,2,3cd)pyrene). The analyses were performed on an Agilent 1100 liquid chromatograph. These compounds were separated on an reverse phase Lichrospher PAH C18 column (25 × 4.6 mm, 5 μm) at 20oC temperature with the following mobile phase program: isocratic acetonitrile–water 60:40 (v/v) in 3 min, gradient acetonitrile–water 100:0 (v/v) in 12 min, isocratic acetonitrile–water 100:0 (v/v) in 15 min, flow 1 ml/min, injection volume 10 μl and were detected at wavelength of 254 nm. RESULTS AND DISCUSSION In order to assess the soil pollution level with organic compounds like TPH, BTEX and PAH generated by mineral oil extraction, by storage of mineral oil and of petroleum residues, were collected soil samples from many depth from three 29

type of zones: extraction oil derrick zone, petroleum deposit zone and oil residue deposit zone. From extraction oil derrick zone were collected soil samples from three representative points of area (A, B, C) , in each case from four depths (0.3, 1, 3 and 5 m). A point was situated at 3 m from the oil derrick, B was situated at 10 m from the oil derrick and C was situated at 20 m from the oil derrick. For these three points were determinated the organic pollutants concentrations (TPH, BTEX, PAH) and the results are presented in Figs 1, 2 and 3. 1800

A B

C

normal value

alert limit

1600

TPH (mg/kg d.m.)

1400 1200 1000 800 600 400 200 0

0.3

1

3 depth (m)

5

Fig. 1. Variation of TPH concentrations in the oil derrick zone 4.5

A B C normal value

4 BTEX (mg/kg d.m.)

3.5 3 2.5 2 1.5 1 0.5 0

0.3

1

3 depth (m)

Fig. 2. Variation of BTEX concentrations in the oil derrick zone

30

5

9 0.3 m

8

1m

3m

5m

normal value

PAH (mg/kg d.m.)

7 6 5 4 3 2 1 0

A

B point

C

Fig. 3. Variation of PAH concentrations in the oil derrick zone

From oil deposit zone were collected samples from three different points: D and E points (situated near deposit) and F point (situated at border of deposit), from four depths (0.3 m, 1 m, 3 m and 5 m). Organic pollutants (TPH, BTEX, PAH) were analysed and the variation of concentration with depths is represented in Figs 4, 5 and 6. 350 300

D

E

F

normal value

TPH (mg/kg d.m.)

250 200 150 100 50 0

0.3

1

3

5

depth (m)

Fig. 4. Variation of TPH concentrations in the mineral oil deposit zone

31

0.09

D 0.3 m

E 0.3 m

F 0.3 m

normal value

0.08

BTEX (mg/kg d.m.)

0.07 0.06 0.05 0.04 0.03 0.02 0.01 0

benzene

toluene

ethylbenzene

xylene

BTEX

Fig. 5. Variation of BTEX concentrations at 0.3 m depth in the oil deposit zone D E

1

F

normal value

0.9 PAH (mg/kg d.m.)

0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0

0.3

1

3

5

depth (m)

Fig. 6. Variation of PAH concentrations in the mineral oil deposit zone

Also, for oil residue deposit zone used for storage of waste petroleum were collected soil samples from two different points (G – situated at 3 m from the waste oil deposit, and M – situated at 7 m from the waste oil deposit) from four depths (0.3, 1, 3 and 5 m). The concentrations of TPH, PAH and BTEX were quantified and presented in Figs 7, 8 and 9.

32

M

900

G

normal value

TPH (mg/kg d.m.)

800 700 600 500 400 300 200 100 0

0.3

1

3

5

depth (m)

Fig. 7. Variation of TPH concentrations in the oil residue deposit zone

PAH (mg/kg dm)

6 5 4 3 2 1 0 0.3

G 1

3

M

5

depth (m)

normal value

Fig. 8. Variation of PAH concentrations in the oil residue deposit zone M

4

G

normal value

BTEX (mg/kg d.m.)

3.5 3 2.5 2 1.5 1 0.5 0

0.3

1

depth (m)

3

5

Fig. 9. Variation of BTEX concentrations in the oil residue deposit zone

From the results of analytical study obtained for the oil derrick zone it was observed that the pollution level increases horizontally with decrease of distance from the oil derrick, the most contaminated samples being from the point situated beside the oil derrick (A). 33

The two samples from surface soil (A0.3 m, A1 m) presented big TPH concentrations (A0.3 m 1718.5 mg/kg d.m.) which were situated in the intervention limit (in conformity with Order 756/1997); PAH concentrations are situated in the alert limit for majority of samples with exception of two samples (C3 m, C5 m, situated at the biggest distance from the oil derrick) for which the concentrations are below the admissible value ( 5 year (%) Building symptom index (mean ± SD)

Total Male Female 1152 (100) 293(23.69) 886(76.31) 88.62 80.27 92.01 32.13±8.06 32.95±8.26 31.86±7.04 71.70 20.92 5.9 1.56

71.44 20.88 3.29 4.39

71.73 20.84 6.71 0.72

0.80

1.09

0.70

73.32 25.88

64.83 34.08

75.97 23.33

42.84 9.35 47.81

36.27 14.28 49.45

44.49 8.18 47.33

13.88 86.12 4.74±3.86

25.64 74.36 4.18±3.72

10.23 89.77 4.91±3.80

71.18 28.82 6.55±2.88

79.12 20.88 6.34±2.79

67.13 32.87 6.61±2.91

No symptom reported only 16.3% of employees, and more than 50% of them reported five or more symptoms (Fig. 1). Frequently reported symptoms were the general symptoms as fatigue (86.6%) and headache (83.2%). Facial-skin symptoms occurred more rarely (scaling/itching scalp or ears – 16.3% and dry, itching hands, red skin – 24.9% ).

115

yes, often yes, sometimes

hands dry, itching, red skin scaling/itching scalp or ears dry or flushed facial skin cough hoarse, dry throat irritated, staffy or runny nose itching, burning or irritation of the eyes difficulties concentrating nausea/dizziness headache feeling heavy-headed fatigue 0

10

20

30

40

50

60

70

Fig. 1. Presence of symptoms among study participants (%)

In Fig. 2 the prevalence of commonly disturbing environmental factors at the work place is presented. It could be said that physical attributes of buildings have high influence on worker well-being. The employees complained most frequently about dry air (75.7%), high indoor temperature (74.9%) and stuffy air (73.5%), whilst the least complaints were about static electricity (47.3%) and about low indoor temperature (45.2%). Their beliefs are dependent on the time the employee spent in the current job. The employees with the working status higher than 5 years in higher percentage believed that their health problems have been attributed to the work environment than people with working status of less than 5 years. more than 5 years

dust of dirt

less than 5 years

dim light or glare/reflections noise static electricity unpleasant odour dry air stuffy air room temperature to low varying room temperature room temperature to high draught 0

10

20

30

40

50

60

70

80

Fig. 2. Relation between believing that symptoms have been attributed to the physical work environment with working age

116

117

Draught Room temperature to high Varying indoor temperature Indoor temperature to low Stuffy air Dry air Unpleasant odour Static electricity Noise Dim light or glare/reflections Dust of dirt

Complaints 1.123 (1.123–2.033) 1.070 (0.627–1.828) 1.425 (0.723–2.810) 1.378 (0.668–2.845) 2.014 (1.076–3.771) 1.613 (0.888–2.932) 1.402(0.774–2.540) 1.948 (1.050–3.616) 1.216(0.628–2.358) 0.728 (0.381–1.392) 1.130 (0.637–2.003)

RR (95% CI)

General symptoms RR (95% CI)

0.701 1.183(0.549–2.546) 0.803 1.396 (0.670–2.910) 0.306 1.053 (0.443–2.504) 0.386 3.932 (1.619–9.554) 0.029 0.912 (0.365–2.277) 0.117   5.557 (2.110–14.636) 0.265 1.798 (0.793–4.078) 0.035 1.512 (0.680–3.365) 0.562 2.026 (0.895–4.586) 0.337 0.497 (0.211–1.174) 0.676 0.879 (0.393–1.962)

P 0.668 0.373 0.908 0.003 0.843 0.001 0.160 0.311 0.090 0.111 0.752

P

Mucous membrane symptoms

Table 3. Binary logistic regression for complaints about environmental factors and risk for high symptoms score

1.267 (0.513–3.127) 1.278 (0.553–2.952) 0.505 (0.160–1.591) 1.489 (0.483–4.592) 0.450 (0.153–1.328) 5.058 (1.652–15.485) 1.019 (0.372–2.792) 2.529 (1.030–6.208) 2.683 (1.064–6.766) 1.016 (0.395–2.609) 1.261 (0.485–3.276)

RR (95% CI)

Skin symptom 0.608 0.566 0.243 0.489 0.148 0.005 0.970 0.043 0.036 0.974 0.634

P

Using binary logistic regression (Table 3), we found that the low room temperature (p= 0.002), dry air (p= 0.015), static electricity (p = 0.007) and noise (p = 0. 024) were the most important factors for the high symptoms score, occured in 395 (34.28%) participants. The results of the study provide data about the highly frequent building-related symptoms in commercial centers. Employees reported a complex of compliants and the prevalence of the symptoms was higher than in other similar studies in industrial countries16–18. We anticipate that one of the reasons could be the structure of the participants. Generally, women have a higher prevalence of sick-building symptom than men19–21. Also, the environment of the workers was not smokefree and it could have influenced the result22 as well. Moreover, a long period of socio-economic crisis in Serbia should be taken into account. A lack of adequate technical supplies appear to contribute these facts. In contrast to other similar studies23,24, training physicians filled out questionnaires during interviews with workers and this way of collecting the data diminished the possibility of uncertainties about some answers. It was also noticed that participants were generally younger than 35, so an unhealthy work environment could have many implication for their health in the future. Other factors (work without legal work contract and health insurance, poor socio-economical situation in the country, high rate of unemployment, etc.) contributed to their job satisfaction. On the other side, the workers are not aware of the importance of these symptoms, since they are not specific and in many cases participants connect them with some other factors, such as seasonal disorders, or allergies. Beside, the symptoms are not permanent and they stop after leaving the building. The mechanisms to explain the symptoms of ‘sick-building syndrome’ have been identified, although acknowledgment of individual symptoms to individual exposures still remains a problem25. Several sets of data identify multiple deficiencies in almost all buildings in which complaints have been identified26–28. Only a few interventions have been done to improve the conditions in the commercial centers. The problem was mainly solved by separate installation of the air conditioning systems into individual premises. From our point of view, this only made the situation in the halls worse: the great number of single air conditioners caused increasing of air temperature. At the same time, many consumers are also affected. Although building-related symptoms in non-industrial workplaces, such as office buildings, have been reported since the early of 1980’s in the industrial countries29–31, there are very few investigations in the peer-reviewed literature among workers in Serbia. We think that public awareness of sick-building syndrome prevalence is crucial to eliminate it. A careful registration of the medical and oc118

cupational history is essential, and the symptom perception must be discussed in details by the physician. Last, but not the least, there are no legislative basis for working environmental control in this field in Serbia. Moreover, periodic general check-up for the nonindustrial employees are not compulsory. The recent studies indicate that it is possible to decrease the building-related symptoms considerably after doing different interventions in the object32 and that many of these symptoms may apparently have remediable causes. In conclusion, the results indicated that employees in commercial centers had an elevated prevalence of building-related symptoms. The study provides support for the hypothesis that the prevalence of sick-building syndrome is high in nonindustrial work places in the countries of transition. The occurrence of detected symptoms may be initiated by numerous integrated risk factors. The environment and characteristics of building could be one of the resons for this state. It is very important to point out this problem and to begin with a systematic supervision of the working conditions and the workers health at the non-industrial work places. Further confirmation studies are necessary to achieve the goal of creating buildings that are healthy for their occupants and suistanable in terms of their general environmental impacts. Acknowledgements. This study was funded by the Ministry of Science and Technological Development (No of Project 21016).

REFERENCES 1. WHO: Regional Office for Europe: Health Aspects Related to Indoor Air Quality. EURO Reports and studies, No 21, Copenhagen, Denmark, 1979. 2. S. Burge, A. HedgE, J. Harris-Bass, A. S. Robertson: Sick-building Syndrome: A Study of 4373 Office Workers. Annals of Occupational Hygiene, 31, 493 (1987). 3. P. L. Oi, K. T. Goh, M. H. Phoon, S. C. Foo, H. M. HYaP: Epidemiology of Sick Building Syndrome and Its Associated Risk Factors in Singapore. Occupational Environmental Medicine, 55, 188 (1998). 4. J. SUNDELL: On the History of Indoor Air Quality and Health. Indoor Air, 14 (7), 51 (2004). 5. WHO: Regional office for Europe: Indoor Air Pollutants, Exposure and Health Effects. EURO Reports and Studies, No 78, Copenhagen, Denmark, 1983. 6. R. Runeson, D. Norback, B. Klinteberg, C. Edling: The Influence of Personality, Measured by the Karolinska Scales of Personality (KSP), on Symptoms among Subjects in Suspected Sick Buildings. Indoor Air, 14 (6), 394 (2004). 7. G. H. HUTTON: The Way We Build Now. Archive of Environmental Health, 58 (8), 505 (2003). 8. J. bourbeau, C. Brisson, S. Allaire: Prevalence of the Sick-building-syndrome in Office Workers before and Six Months and Three Years after Being Exposed to a Building with an Improved Ventilation System. Occupational and Environmental Medicine, 54, 49 (1997).

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  9. R. Neuner, H. J. Seidel: Adaptation of Office Workers to a New Building – Impaired Wellbeing as Part of the Sick-building-syndrome. International J. of Hygiene and Environmental Health, 209, 367 ( 2006). 10. D. Nikic, D. Stojanovic: Sick Building Syndrome-A Result of Modern Lifestyle. Srpski Arhiv za Celokupno Lekarstvo, 132 (7–8), 240 (2004) (in Serbian). 11. M. Nikolic, D. Nikic, K. Lazarevic: Exposure to Environmental Tobacco Smoke and Respiratory Symptoms in School Children of Niš. Srpski Arhiv za Celokupno Lekarstvo, 134 Suppl 2, 104 (2006) (in Serbian). 12. L. J. Stosic, S. Milutinovic, M. Nikolic, D. Nikic, O. Radulovic, A. Stankovic: Indoor Exposure to Chemical and Biological Agents and Health Effects in Primary Health Children. Central European J. of Medicine, 1 (4), 379 (2006). 13. D. VELJKOVIc: Bioaerosols as Risk Factor in Occurence of the Sick Building Syndrome in Commercial Centers. Masther Thesis, University of Nis, 2005. 14. K. Andersson, G. Stridh, I. Fagerlund, B. Larsson: The MM-questionnaires – A Tool when Solving Indoor Climate Problems. Department of Occupational and Environmental Medicine, Örebro University Hospital, Örebro, Sweden, 1993. 15. D. Nikic, D. BOGDANOVIc, M. Nikolic, A. Stankovic, N. ZIVKOVIC, A. DJORDJEVIC: Air Quality Monitoring in Nis (Serbia) and Health Impact Assessment. Environmental Monitoring and Assessment. PubMed – as supplied by publisher, 2008. 16. K. Skyberg, K. R. Skulberg, W. Eduard, E. Skaret, F. Levy, H. KJUUS: Symptoms Prevalence among Office Employees and Associations to Building Characteristics. Indoor Air, 13 (3), 246 (2003). 17. B. Stenberg, K. Hansson Mild, M. SandstrÖm, J. Sundell, S. WAll: A Prevalence Study of the Sick Building Syndrome (SBS) and Facial Skin Symptoms in Office Workers. Indoor Air, 3, 71 (1993). 18. P. Wargocki, D. P. Wyon, Y. K. BAIK, G. clausen, P. O. erFANGER: Perceived Air Quality, Sick Building Syndrome (SBS) Symptoms and Productivity in an Office – Two Different Pollution Loads. Indoor Air, 9, 165 (1999). 19. B. Stenberg, S. Wall: Why Do Women Report ‘Sick Building Symptoms’ More Often than Men? Socal Science & Medicine, 40 (4), 491 (1995). 20. C. Gijsbers van Wijk, A. M. KOLK: Sex Differences in Physical Symptoms: the Contribution of Symptom Perception Theory. Socal Science & Medicine, 45 (2), 231 (1997). 21. S. Brasche, M. Bullinger, M. Morfeld, H. J. Gebhardt, W. Bischof: Why Do Women Suffer from Sick Building Syndrome More Often than Men? – Subjective Higher Sensitivity versus Objective Causes. Indoor Air, 11, 217 (2001). 22. T. MIZOUE, K. REIJULA, K. ANDERSSON: Environmental Tobacco Smoke Exposure and Overtime Work as Risk Factors for Sick Building Syndrome in Japan. American J. of Epidemiology, 154, 803 (2001). 23. M. Lahtinen, C. Sundman-Digert, K. REIJULA: Psychosocial Work Environment and Indoor Air Problems: A Questionnaire as a Means of Problem Diagnosis. Occupational and Environmental Medicine, 61 (2), 143 (2004). 24. K. REIJULA, C. Sundman-Digert: Assessment of Indoor Air Problems at Work with a Questionnaire. Occupational and Environmental Medicine, 61 (1), 33 (2004). 25. M. Hodgson: Indoor Environmental Exposures and Symptoms. Environmental Health Perspective, 110 (4), 663 (2002). 26. J. E. Woods: Cost Avoidance and Productivity in Owning and Operating Buildings. Occupational Medicine, 4 (4), 753 (1989). 27. P. L. Oi, K. T. Goh, M. H. Phoon, S. C. Foo, H. M. Yap: Epidemiology of Sick Building Syndrome and Its Associated Risk Factors in Singapore. Occupational and Environmental Medicine, 55, 188 (1998).

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28. C. Brauer, C. KOLSTAD, P. ORBAEK, M. Mikelsen: Non Consistent Risk Factor Pattern for Symptoms Related to the Sick Building Syndrome: A Prospective Population-based Study. International Archive of Occupational and Environmental Health, 79 (6), 453 (2006). 29. K. Andersson: Epidemiological Approach to Indoor Air Problems. Indoor Air, Suppl. 4, 32 (1998). 30. A. F. Marmot, J. Eley, M. Stafford, S. A. Stansfeld, E. Warwick, M. G. MARMOT: Building Health: An Epidemiological Study of ‘Sick Building Syndrome’ in the Whitehall II Study. Occupational and Environmental Medicine, 63 (4), 283 (2006). 31. H. Nakazawa, H. Ikeda, T. Yamashita, I. Hara, Y. Kumai, G. Endo, Y. ENDO: A Case of Sick Building Syndrome in a Japanese Office Worker. Industrial Health, 43 (2), 341 (2005). 32. H. J. Chao, J. Schwartz, D. K. Milton, H. A. BURGe: The Work Environment and Workers’ Health in Four Large Office Buildings. Environmental Health Perspective, 111 (9), 1242 (2003). Received 25 November 2008 Revised 15 January 2009

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Journal of Environmental Protection and Ecology 11, No 1, 122–129 (2010) Ecology

Structural responses of Platanus orientalis L. leaves to elevated CO2 concentration and high temperature D. Kolevaa*, M. Stefanovaa, Ts. Ganevaa, V. Velikovab, Ts. Tsonevb, Fr. Loretoc Faculty of Biology, Sofia University ‘St. Kliment Ohridski’, 1000 Sofia, Bulgaria E-mail: [email protected] b Institute of Plant Physiology, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria c CNR – Istituto di Biologia Agroambientale e Forestale, 00 016 Monterotondo Scalo (RM), Italy a

Abstract. Anatomical structure of the leaves and the leaf surface of two-year-old Platanus orienta­ lis L. plants after treatment with elevated СО2 (800 ppm) and high temperature (38oC for 4 h) were studied. Light microscopy analysis (LM) revealed that the examined stress factors have the strongest effect on the photosynthesising parenchyma of the leaves. They cause changes of the shape and structure of the photosynthetic cells and increase the apoplast volume in the spongy tissue. The most prominent effect on the tissue structure of expanding leaves has the combined treatment with stress factors. Scanning electron microscopy (SEM) analysis showed that elevated СО2 stimulates wax formation in expanding leaves as epidermal reaction in stress conditions. Keywords: leaf, anatomical structure, cuticle, elevated СО2, high temperature, Platanus orientalis L.

AIMS AND BACKGROUND Environmental factors, which affect plants as external facts, cause different kinds of responses. High troposphere concentration of CO2 is a factor with considerable consequences for forest tree productivity and stability of the forest ecosystems1. At the same time, the high temperature is a limiting factor for plant growth, photosynthesis and respiration2. The negative effect of the Global warming and increased CO2 concentration in the atmosphere is most visible in forest ecosystems. Aim of a lot of studies is to establish the relationship between structure and function of the photosynthetic apparatus in response to abnormal values of CO2 and temperature. Object of the major part of these structural examinations are herbaceous plants3–5, while the examined woody plants are considerably less4,6. Examining the effects of acidic precipitation and low temperature7 and plant responses to air pollutants8 *

For correspondence.

122

Finland scientists obtained representative data about the state of the coniferous forests. Complex structural and functional studies of plants under stress environmental factors have been a permanent tendency lately. This provides answers of some current questions: (1) How the high temperature and elevated СО2 influence the structural organisation and functional parameters of the photosynthetic apparatus? (2) What is the adaptive mechanism for detoxication, which has been occurred in different levels of organisation of the photosynthetic apparatus? (3) Is it possible the complex examination of wide spread woody plant species, grown in controlled conditions, to identify the effect of elevated СО2 and high temperature, to clarify the mechanisms of detoxication and obtained results to serve as a basis of future prognostic examination of these species in natural conditions? The present work is a part of a complex structural and functional study on the photosynthetic apparatus of 2-year-old Platanus orientalis plants, grown in controlled conditions in greenhouse and climatic chamber and treated with high temperature and elevated СО2. The aim of a part of the structural study is to establish the morphological changes in photosynthetic apparatus, leaf tissues and leaf surface with the methods of light microscopy (LM) and scanning electron microscopy (SEM) caused by the stress factors elevated СО2 and high temperature. EXPERIMENTAL Two-year-old Platanus orientalis (a strong isoprene emitter9) plants were grown in a greenhouse until appearance of the first leaves. Plants were regularly watered to keep soil at full water capacity, and were fertilised once a week with full-strength Hoagland solution. After appearance of the first leaves, plants were transferred to a climatic chamber under controlled conditions, namely 350 µmol m–2 s–1 photon flux density, 25°/20°C ± 2°C of day/night temperature, 65% of relative humidity, and 12 h of photoperiod. Plants were grown under these conditions for 1 month before starting the treatment. After that, plants were divided in two groups and transferred to two climatic chambers supplied with two different CO2 concentrations – 380 ppm (ambient CO2 level), and 800 ppm (elevated CO2). In both chambers controlled conditions of other parameters were also ensured, namely 350 µmol m–2 s–1 photon flux density, 25°C ± 2°C temperature, 65% relative humidity, and 12 h photoperiod. Plants were grown under these conditions for 1 month. Leaves termed as ‘mature’ already reached their fully expanded state when the 800 ppm CO2 fumigation was implemented, while leaves termed as ‘expanding leaves’ developed and reached maturity during the fumigation. High temperature (38°C) was applied to whole plants from both groups for 4 h to simulate exposure to a heat wave. The heat wave experiment was performed after the four weeks fumigation with the two different CO2 levels. 123

Light microscopy. Segments from the middle parts of the primary leaf were fixed in 3% glutaraldehyde and used for light microscopy studies. The thicknesses of the lamina, the mesophyll, the palisade and spongy parenchyma were measured. Leaves were cut by hand. Ten morphometric measurements were repeated in triplicate and microphotographs were taken using an Amplival 4 microscope (Carl Zeiss, Jena, Germany). Scanning electron microscopy (SEM). Segments from the middle parts of lamina were taken and fixed in 3% glutaraldehyde (pH 7.4) for 12 h at 4oC. Then the leaf tissue was dehydrated in ethyl alcohol. The samples were covered with 0.1 nm golden layer in vacuum-evaporator Jeol JFC-1200 fine coater and observed by using a scanning electron microscope Jeol JSM-5510 at cathode voltage of 10 kV. RESULTS AND DISCUSSION Leaf structure. The leaf of sycamore (Platanus orientalis) is dorsi-ventral and hypostomatic. Adaxial epiderma consists of one-layer big uniform cells, while the cells of abaxial epiderma are considerably smaller. Photosynthesising parenchyma in mature and expanding leaves is composed of one-layer palisade tissue and 2–3layer spongy parenchyma (Fig. 1А). Around the spongy parenchyma cells there are well-distinguished intracellular spaces, larger near the stomata complex. All examined expanding leaves of the control plants, in comparison with mature ones, have 20% smaller average thickness of the palisade tissue and 10% – of the spongy tissue (Table 1). Despite this, the values of the palisade factor of both expanding and mature leaves are almost equal (61.29 and 58.24%) and their reaction in the experiment will not depend on morfometric differences between the photosynthetic tissues. Table 1. Thickness (μm) of leaf lamina and its tissues and palisade factor (%) in sycamore plants, treated with elevated СО2 and high temperature

Variants

Palisade Spongy Palisade parenchyma parenchyma factor 25oC mature leaf 188.80±7.54 128.64±7.66 85.12±11.70 53.76±10.10 61.29 380 ppm expanding 172.16±26.89 120.96±21.43 67.84±12.14 48.64±9.15 58.24 СО2 leaf 1 month mature leaf 203.52±15.91 148.95±21.63 74.88±6.07 65.28±11.99 53.42 25oC expanding 177.28±23.96 122.88±19.51 72.96±9.64 51.20±13.49 58.76 800 ppm leaf СО2 4 h 38oC mature leaf 181.12±10.03 129.92±10.03 63.36±2.02 65.92±8.01 49.01 380 ppm expanding 178.56±24.41 122.24±23.26   63.36±19.89 51.20±12.80 55.31 СО2 leaf 4 h 38oC mature leaf 177.92±12.73 121.60±10.01 66.56±4.47 55.04±7.51 54.74 800 ppm expanding 200.96±23.79 146.56±18.21 74.88±6.07 71.68±13.76 51.09 СО2 leaf

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Lamina

Mesophyll

 

  Fig. 1. Anatomical structure of mature and expanding leaves in control plants and after elevated CO2 and high temperature (38oC for 4 h) treatment. A – climatic chamber under controlled conditions, mature control leaf; B – 25oC, elev. CO2, mature leaf; C – 25oC, elev. CO2, expanding leaf; D – 38oC for 4 h, elev. CO2, expanding leaf [× 200] AbE – abaxial epidermis; AdE – adaxial epidermis; P – palisade parenchyma; S – spongy parenchyma

The effect of elevated СО2 is most distinguished in the structure of mature leaves photosynthesising parenchyma. The thickness of the mesophyll increases by 16%, but more interesting is the fact that the average thickness of the palisade tissue diminishes by 12% while the average thickness of the spongy tissue rises by 21%. Thus, the palisade factor decreases by about 7% (53.42%). Light microscopy analysis revealed that apoplast volume of spongy tissue has been enlarged by means of changing the cell shape and visible reduction of the symplast (Fig. 1В). Concerning expanding leaves, the effect of elevated СО2 on the anatomic structure is not so distinguished. These morphometric deviations, despite nonessential, are quite well visible because of change of the palisade cells form (Fig. 1С). Their anticlinal walls are undulate and the cells have not typical cylindrical form. In the experimental conditions, the effect of factor ‘temperature’ caused unexpected histological changes. In mature leaves, the reduction of abaxial epidermis by 18% and of the palisade tissue by 26% was established. At the same time the spongy parenchyma increases its average thickness by 23%, and as a result the palisade factor is low – 49%. The quantitative changes do not perform structural manifestation. 125

Elevated СО2 and high temperature applied in combination on mature leaves cause diminish of the average thickness of photosynthesising parenchyma due to the lower thickness of palisade tissue. This is not in relation with any morphologic changes of the cells. Opposite tendency was established for expanding leaves. The average thickness of the leaf lamina is higher due to the increase of the thickness of photosynthesising parenchyma by 21%. During this type of treatment, the raise of the average thickness of spongy parenchyma is about 47%. This tissue has larger volume of the apoplast due to changes in shape, size and arrangement of the cells (Fig. 1D). Structural responses of the leaf tissue to еlevated СО2 and high temperature in our examination are in correlation with results, obtained from examination of woody plants treated with ozone, acid rain and low temperature7,10,11. Almost the same is the influence of ultraviolet-B radiation on the leaf anatomy of cotton12. In another study with aspen and birch elevated CO2 tended to increase the thickness of leaf and spongy mesophyll layer and intercellular air space volume in mesophyll13. The authors search for subordination between cell surface area, intercellular air space, apoplast volume and cell wall thickness and vacuole volume. For this reason the specified anatomical changes in Platanus must be considered only as universal type structural reaction in tissue level but not as destructive changes. In our experiment elevated СО2 is the factor that most strongly affects the leaf structure both in mature and expanding leaves. The combined influence of elevated СО2 and high temperature affects the leaf structure only in expanding ones. They show various types of tissue structure reaction, which presume more effective histological adaptation to extreme conditions. The cause of considerable morphometric changes in mature leaves after 4-hour treatment with 38oC remains unidentified. Surface structure of the leaves. SEM analysis of leaf surface in mature and expanding leaves revealed smooth cuticle, with well-shaped cuticle rims, which outline the epidermal cells both of adaxial (Fig. 2А) and abaxial (Fig. 2В) epiderma. Stomata are of cyclocytic type, almost evenly distributed in abaxial epiderma. The external rims and walls of stomata guard cells are thickened (Fig. 2В). In expanding leaves cuticle waxes have been observed on both leaf surfaces. The cuticle wax deposits are plates over the cuticle rims of the abaxial cuticle (Fig. 2С) and granules on the rest part of the leaf surface. (Fig. 2D, E and F).

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  Fig. 2. SEM analysis of adaxial cuticle (A) and abaxial cuticle (B) of expanding leaves in control plants and after treatment with elevated CO2 and high temperature (38oC for 4 h.) (C and D – adaxial cuticle, E and F – abaxial cuticle); CW – cuticular waxes

Recent examinations consider wax generation in plants, grown in extreme conditions, as a response with adaptive value based on stress resistance physio­ logical and biochemical mechanisms in ontogenic and phylogenic aspect14. Wax deposition is often a response to water stress and this can occur rapidly within few days15,16. These data give us foundation to presume that in our experiment with examined species it is absolutely possible the treatment with elevated СО2 to stimulate wax deposition. Data obtained from studies of other woody plants support our assumption. It was found out that elevated СО2 alone and in combination with O3 increased wax coverage on the abaxial leaf surface of an inland clone of 127

pubescent birch (Betula pubescens)17. Some of the major outstanding issues are the mechanisms of wax deposition onto the cuticle surface, control of composition at genetic, molecular and morphological levels, and how environmental pressures elicit an adaptive response14. CONCLUSIONS Light microscopy analysis of the experimental leaf material provides information about various types of structural reactions. The most significant are the changes in photosynthesising parenchyma, particularly cell form, symplast connection between cells and organisation of the apoplast in the spongy parenchyma. Morphometric measurements reveal that the еlevated СО2 enlarges the apoplast volume in mature leaves spongy tissue and changes the shape and probably the structure of the expanding leaves palisade cells. The data, achieved for expanding leaves, revealed that their morpho-anatomical features are more stable towards 4-hour temperature treatment than these of mature leaves. Obviously, the combined application of elevated СО2 and high temperature in experimental conditions affects expanding leaves more than mature ones. SEM analysis shows that for examined species the elevated СО2 causes formation of cuticle waxes onto the both leave surfaces as an adaptive reaction in stress conditions. Aknowledgements. This research was supported by Bulgarian National Science Fund (contract TKB-1604/2006).

references 1. C. D. Keeling, T. P. Whort, M. Wahlen, J. van der Plicht: Interannual Extremes in the Rate of Rise of Atmospheric Carbon Dioxide since 1980. Nature, 375, 666 (1995). 2. A. Mostowska: Environmental Factors Affecting Chloroplasts. In: Handbook of Photosynthesis (Ed. M. Pessarakli). Marcel Dekker, New York, 1997, 407–426. 3. J. Kutik, L. Natr, H. H. Demmers-Derks, D. W. Lawlor: Chloroplast Ultrastructure of Sugar Beet (Beta vulgaris L.) Cultivated in Normal and Elevated CO2 Concentrations with Two Contrasted Nitrogen Supplies. J. Experimental Botany, 46 (293), 1797 (1995). 4. O. Sam, M. Nunez, M.C. Ruiz-Sanchez, J. Dell’Amico, V. Falcon, M. C. de la Rosa, J. Seoane: Effect of Brassinosteroid Analogue and High Temperature Stress on Leaf Ultrastructure of Lycopersicon esculentum. Biologia Plantarum, 44 (2), 213 (2001). 5. M. Lambreva, D. Stoyanova-Koleva, G. Baldjiev, T. Tsonev: Early Acclimation Changes in the Photosynthetic Apparatus of Bean Plants during Short-term Exposure to Elevated CO2 Concentracion under High Temperature and Light Intensity. Agriculture, Ecosystems and Environment, 106, 219 (2005). 6. A. Noormets, A. Sober, E. J. Pell, R. E. Dickson, G. K.Podila, J. Sober, J. G. Isebrands, D. F. Karnovsky: Stomatal and Non-stomatal Limitation to Photosynthesis in Two Trembling Aspen (Populus tremuloides M i c h x.) Clones Exposed to Elevated CO2 and/or O3. Plant, Cell and Environment, 24, 327 (2001).

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  7. J. BÄck, S. Huttunen, U. Kristen: Carbohydrate Distribution and Cellular Injuries in Acid Rain and Cold-treated Spruce Needles. Trees, 8, 75 (1993).   8. M. Turunen, S. Huttunen: A Review of the Response of Epicuticular Wax of Conifer Needles to Air Pollution. J. Environ. Qual., 19, 35 (1990).   9. X. Zhang, Y. Mu, W. Song, Y. Zhuang: Seasonal Variations of Isoprene Emissions from Deciduous Trees. Atmospheric Environment, 34, 3027 (2000). 10. J. Reinikainen, S. Huttunen: The Level of Injury and Needle Ultrastructure of Acid Rain-irrigated Pine and Spruce Seedlings after Low Temperature Treatment. New Phytol., 112, 29 (1994). 11. E. Paakkonen, M. GÜnthardt-Goerg, T. Holopainen: Responses of Leaf Processes in a Sensitive Birch (Betula pendula R o t h) Clone to Ozone Combined with Drought. Annals of Botany, 82, 49 (1998). 12. V. G. Kakani, K. R. Reddy, D. Zhao, A. R. Mohammed: Effects of Ultraviolet-B Radiation on Cotton (Gossypium hirsutum L.) Morphology and Anatomy. Annals of Botany, 91, 817 (2003). 13. E. Oksanen, J. Sober, D. F. Karnosky: Impact of Elevated CO2 and/or O3 on Leaf Ultrastructure of Aspen (Populus tremuloides) and Birch (Betula papyrifera) in the Aspen FACE Experiment. Environmental Pollution, 115, 437 (2001). 14. T. Shepherd, D. W. Griffiths: Tansley Review: The Effects of Stress on Plant Cuticular Waxes. New Phytologist, 171, 469 (2006). 15. C. Bengston, S. Larsson, C. Liljenberg: Effect of Water Stress on Cuticular Transpiration Rate and Amount and Composition of Epicuticular Wax in Seedling of Six Oat Varieties. Physiologia Plantarum, 44, 319 (1978). 16. G. S. Premachandra, H. Saneoka, M. Kanaya, S. Ogata: Cell Membrane Stability and Leaf Surface Wax Content as Affected by Increasing Water Deficits in Maize. J. of Experimental Botany, 42, 161 (1991). 17. R. Vanhatalo, S. Huttunen, J. BÄck: Effects of Elevated [CO2] and O3 on Stomatal and Surface Wax Characteristics on Leaves of Pubescent Birch Grown under Field Conditions. Trees–Structure and Function, 15, 304 (2001). Received 18 March 2008 Revised 25 April 2008

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Journal of Environmental Protection and Ecology 11, No 1, 130–136 (2010) Ecology

Photopollution impacts and side effects on the ecosystem as well as on the economy P. S. Karagkiozidis School advisor of Central Macedonia, Greece E-mail: [email protected] Abstract. Photopollution, else known as light pollution, is a phenomenon that the general public is not familiar with. It is considered as a problem that only astronomers face, where in fact the issues that are derived from it, are concerning the welfare of us all. Based on the idea that this phenomenon refers only to astronomers its definition is incomplete. Therefore a new definition is necessary, which will include all its consequences. Keywords: photopollution, light pollution, definition, green house effect, glare, astronomers.

AIMS AND BACKGROUND The aim of the present paper is to present a new, complete definition of light pollution and to explain the reason why we should do so, to point out the consequences derived from it, to inform the general public and to suggest solution for its reduction. Artificial illumination consists one of the most useful and integral parts of the human civilisation as it allows all human activities to expand during the night or to take place in areas where the lighting is inadequate. Its misuse, though, causes a phenomenon known as photopollution/light pollution/luminous pollution. This phenomenon is caused because artificial light is being reflected from the various components of the atmosphere. Astronomers (professional and amateur) are familiar with this issue The definitions of photopollution that exist so far are rather inadequate. In this paper is suggested a new definition, and the consequences of it are presented. In brief the most severe consequences of photopollution are: ecological, financial, prevention of the sighting of the night starlit sky and cause glare in general, and contribution to the Greenhouse effect. The integral relation between photopollution and the greenhouse effect is also mentioned. The nocturnal illumination is accomplished exclusively with the consumption of electricity. The atmosphere is being aggravated with almost 1 kg of carbon dioxide (CO2) for each consumed kWh that is with 509 l of carbon dioxide calculated in standard conditions. The greatest contribution to the greenhouse effect possesses carbon dioxide because it is found in very large quantities1. 130

Experimental DEFINITION

First of all we must give the appropriate definition of light pollution. Various definitions exist so far, such as: ‘Photopollution is the prevention of sighting celestial objects due to artificial lighting.’ (Ref. 2). Personally I disagree because definitions such the above focuses only on a small part of the problem. Particularly, it describes photopollution in the sense that observers of the sky understand it, and it does not include the glare that is caused to the drivers from the mismanufacture or the mishandling of the luminaries placed on the streets. In addition it does not include the nuisance that these luminaries may cause when they lighten our residences as sometimes are responsible for insomnia problems. In order for the definition to be complete, it should be a definition similar to the definition of noise pollution or the pollution in general. The definition of noise pollution is: ‘Noise pollution is the phenomenon where distracting and irritating sounds prevent the hearing of desired sounds or they cause discomfort due to their magnitude’ (Ref. 3). Therefore, the photopollution could be defined as the disturbing or irritating lighting which prevents the sighting of objects we wish to see or causes nuisance. SOLVE LIGHT POLLUTION IMPACTS BY TALKING THROUGH

In order to face the impacts of light pollution, it is absolutely necessary to manufacture all the outdoor luminaries in such a way that the light is pointing only the objects that are designed to light. For instance, the street luminaries should only lighten the roadway, because otherwise the phenomenon of glare is caused to the drivers and, therefore, their visibility is reduced. Furthermore a number of measures could contribute to the resolution of this problem, such as sending written information to the competent local agencies and inform the general public. PREVENTION OF SIGHTING THE NIGHT SKY

Photopollution contributes to the creation of a bright background, which prevents the sighting of celestial objects. If someone tries to observe the night sky from an area with photopollution, he will only see the moon and some shiny stars without good resolution. On the other hand, from areas without photopollution, we could observe with a naked eye: the colours of the stars, some very faint stars, star clusters and nebulae. Also we could distinguish asterisms and finally observe the place transition of shiny planets mainly Jupiter and Venus in the vault in one-year time or even in a three-month period. 131

By means of optical equipment we can always penetrate deeply into the Universe. The celestial view has always been a source of inspiration for every human, regardless their occupation: scientists, litterateurs, artists or philosophers. Every human being has philosophical wonderings. We have all felt the unspeakable traction and the awe looking at the sky, as we believed for instance, out of instinct, that the sky holds the secrets of our existence or the answers about extraterrestrial creatures. Unfortunately, at our time there are teenagers that due to the photopollution phenomenon have never had the chance to face and admire the night sky, far away from the city lights during a moonless night (Fig. 1).

Fig. 1. Prevention of sighting the night sky

ECOLOGICAL CONSEQUENCES

The powerful illumination during the night disorientates the nocturnal animals, mainly insects and birds as well as the see turtles, disturbing the balance of the ecosystem4. ECONOMICAL CONSEQUENCES

According to a survey that was carried out in the United States of America a great part of the outdoor illumination is being wasted, since an amount of 30% lightens the sky, thus there is a huge damage loss that exceeds one point half billion dollars per year. In the percentage above it is not included the part that lightens areas that is not supposed to, like nearby buildings and landfills. ‘We spend billions of dollars every year in order to illuminate the belly of birds and airplanes’ underlined the American astronomer David Crawrord, one the founders of International Dark Sky Association5. In Greece the damage loss is much greater due to the very poor quality of the street luminaries. We are all familiar with the round shaped luminaries that lighten the cities, the villages and many private places, all of which mainly lighten the sky (Figs 2 and 3). 132

Figs 2 and 3. Street luminaries in Greece

According to the local records, at the area of Attica in 1997, 13.7×106 kWh have been wasted in order to vainly lighten the sky and the same number for Thessaloniki is 3.53 ×106 kWh (Ref. 6) In my opinion the financial consequences may be the only reason that could bring into action the governments of the states in order to deal with this phenomenon and actually contribute to its resolution.

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Results and discussion CONTRIBUTION TO THE GREENHOUSE EFFECT

The nocturnal illumination is accomplished exclusively with the consumption of electricity. The atmosphere is being aggravated with almost 1 kg of carbon dioxide (CO2) for each consumed kWh that is with 509 l of carbon dioxide calculated in standard conditions1. The data above applies for the European Union countries, which possess several types of electricity plants. The stations producing electricity from wind power, solar energy, waterpower as well as the nuclear plants, do not burden the atmosphere with carbon dioxide emissions. All the units that produce electric power by consuming mineral fuels thought, release large quantities of carbon dioxide into the atmosphere. More specifically the quantity of the produced CO2/kWh that corresponds to each fuel type is shown below1: According to the WWF for the European Union countries Natural gas     0.52 kg Coal        0.92 kg Lignite       1.25 kg

According to the Technological Institution of Kozani for Greece natural gas     0.40 kg lignite       1.2 kg

According to the WWF report, considering the 30 most polluting electricity units in Europe in 2006, the power station of PPC in Agios Dimitrios Ptolemaida and in Kardia Kozani occupied the first and the second place, respectively, as far as the pollution of the atmosphere with greenhouse gasses is concerned. In particular, the Steam Electric Station in Agios Dimitrios occupies the first place in the index with the emissions to reach 1.350 g of CO2/kWh and 12.5 million t of CO2 per year! At the second place we find the Steam Electric Station of Kardia with the emissions to reach 1.250 g CO2/kWh and 8.8 million t per year7. SHORT DESCRIPTION OF THE GREENHOUSE EFFECT

Some gases have the capacity to absorb solar radiation, contributing this way to the raise of the average temperature of the atmosphere and thus being responsible for global warming. This phenomenon is known as the greenhouse effect. The main gases that contribute to the greenhouse effect are: carbon dioxide, methane and nitrogen oxides. From these gases the greatest contribution to this phenomenon possesses carbon dioxide, not because it absorbs a greater amount of radiation per unit of mass or volume from the other gases, but because it is found in very large quantities. 134

The phenomenon described above should not be confused with the spread and the shrinkage of the glaciers as a consequence of periodic cooling and heating of the planet which is due to the periodic change of the eccentricity of the orbit of the Earth (Cycle of Milankovic) (Fig. 4) (Ref. 8).

Fig. 4. Glacier Trift, greenhouse effect

CONCLUSIONS To sum up, photopollution should not only be considered as a problem to the astronomers but plus as a problem to the general public. Moreover citizens should be informed about the above mentioned consequences of photopollution in order for them to be part of the solution of the phenomenon and start to demand from the local authorities to take measures in order to resolve it. REFERENCES 1. R. Currie, B. Elrick, M. Ioannidi, C. Nicolson: Electricity Consumption and Carbon Dioxide, Renewables in Scotland. University of Strathclyde, http://www.esru.strath.ac.uk/EandE/ Web_sites/01-02/RE_info/C02.htm#Electricity%20Consumption%20and%20Carbon%20Diox ide, May 2002. 2. V. Klinkenborg: Our Vanishing Night National Geographic Magazine. International Dark Sky Association (IDA), http://www.darksky.org, November 2008 3. D. Miglani – LLM from M. D. U. Rohtak: Noise Pollution: Sources, Effects and Control, Legal Service India.com, http://www.legalserviceindia.com/articles/noip.htm 4. T. Longcore, C. Rich: Ecological Light Pollution. Front Ecol Environ., 2 (4), 191 (2004). http://www.urbanwildlands.org/Resources/LongcoreRich2004.pdf.

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5. D. Crawford: Light Pollution Debate. http://archives.cnn.com/2002/TECH/science/03/28/ crawford/, CNN, March 28, 2002 Posted: 8:08 PM EST (0108 GMT). 6. P. SOYLIOTIS: Photopollution Map of the Balkan Peninsula. http://parnitha.pblogs.gr/2009/02/ harths-fwtorypanshs-balkanikhs-hersonhsoy.html, 2006. 7. WWF International: Dirty Thirty – Europe’s Worst Climate Polluting Power Stations. http://assets.panda.org/downloads/dirty30rankingfinal260905.pdf, 2005. 8. S. Rutherford: Milankovitch Cycles in Paleoclimate. http://deschutes.gso.uri.edu/~rutherfo/ milankovitch.html, 2004. Received 16 May 2008 Revised 20 July 2008

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Journal of Environmental Protection and Ecology 11, No 1, 137–146 (2010) Ecology

Maize growing under regulated water deficit irrigation without nitrogen fertilisation A. Mateva*, Hr. Kirchevb Department of Melioration, Agricultural University, 12 Mendeleev Street, Plovdiv, Bulgaria E-mail: [email protected] b Department of Crop Production, Agricultural University, 12 Mendeleev Street, Plovdiv, Bulgaria a

Abstract. The aim of the experiment was to establish the grain productivity of maize grown in the region of Plovdiv (Bulgaria) without fertilisation under water deficit conditions. The experimental work was carried out on Mollic fluvisols (FAO–UNESCO) in the period 2004–2007. The variants set in the field experiment were: 100% of the irrigation rate, 75, 50 and 25% reduction of it and a control variant without irrigation. The yield from the non-irrigated maize was within the range of 4.8–11.8 t/ha (8.7 t/ha in average). The yield varied throughout the years of study, when the water regime got better and at the full irrigation rate it was within the range of 11.3–12.6 t/ha (11.9 t/ha in average). The yield after 25% reduced irrigation was practically the same (11.2–12.6 t/ha). The maize yields obtained under experimental conditions were high and the production itself – ecologically sound. Keywords: maize growng, water deficit conditions, nitrogen fertilisation.

aims and background Studies on maize response to irrigation and fertilisation showed unidirectional results. Existing data in available literature show both the separate effect of each of the factors and their interaction. In the last 1–2 decades more concern has been expressed about the production of ecologically sound agricultural goods, which is more often related to obtaining lower yields from the respective crop, including maize. There is no denying the fact that the irrigation water sources are gradually diminishing and that necessitates finding out optimising decisions leading to a maximum economic effect of growing the crop under the conditions of water deficit. Bulgaria is located in the zone of the transitional continental climate characterised by insufficient in amount and unevenly distributed vegetation rainfalls, due to which irrigation is an indispensable part of the agrotechnique for most of the crops. *

For correspondence.

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According to Zhivkov1, in the region of Sofia the maize yield under irrigation could increase from several percent to several times depending on the annual conditions. The number of irrigations is from 3 to 5 and the irrigation rate – 60 mm. Those results were also confirmed by Davidov2, Kirkova3 and Varlev et al.4 Similar data were published by Encin5 according to whom in the region of Fundulea (Romania) maize needed 2–5 irrigations for obtaining yields from 7500 to 11 900 kg/ha. The author established that when reducing the irrigation rate by 25, 50 and 75% of the optimum rate, the yield decreased by 5.6, 29.0 and 51.1%, respectively. Those losses were significant and they could be used for an economic analysis after establishing the yield–water relationship. Irrigation had a decisive effect in maize production in the region of Adana (Turkey) as it increased the yield over three times6. Under the conditions of Slovakia the water factor optimisation resulted in a significant yield increase and it was 2.2 times higher in average compared to the yield from non-irrigated maize7. At the same time, when increasing the nitrogen fertilisation rates, the yield increase was from 7–8 to 20 %. After 12-year studies carried out in Germany, Martin8 announced that when maintaining soil moisture within the limits of 70% of the available one for the layer 0–60 сm, the yield increased by 3000 kg/ha at an irrigation rate of 180 mm in comparison with the yield obtained without irrigation. When increasing the nitrogen fertilisation rate from 150 to 300 kg/ha the yield increased by 2% under non-irrigation and by 7–9 % when the crop was grown under irrigation. The results in the mentioned literature references were the reason to carry out experiments with reducing the fertilisation rates in combination with economically substantiated disturbance of the optimum irrigation regime of the maize crop for grain production in regions of unstable natural wetting. The aim of the present study was to establish the effect of the relatively permanent water deficit on the maize grain productivity when growing the crop without fertilisation in the region of Plovdiv. experimental The experiment was carried out in the period 2004–2007 in the region of Plovdiv on alluvial-meadow soil (Mollic fluvisols). The late hybrid Knezha-613 grown after soya was used. The following variants with different water supply of the crop during the vegetation period were tested: 1. Non-irrigated; 2. Irrigation at pre-irrigation humidity of 75% of the water-holding capacity of the layer 0–80 cm; 3. The same irrigation as in variant 2 but applying 75% of the calculated irrigation rate;

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4. The same irrigation as in variant 2 but applying 50% of the calculated irrigation rate; 5. The same irrigation as in variant 2 but applying 25% of the calculated irrigation rate. The irrigation rates in variant 2 were calculated for watering the respective soil layer up to the water-holding capacity and in the rest of the variants the necessary reduction was made. The experiment was set by the plot method in 4 repetitions. The results of the yields by variants and repetitions were statistically processed using the specialised programme BIOSTAT 1.0. The yield–water relationship was established by a regression analysis. Results and Discussion The irrigation regime parameters and the effect of irrigation on maize productivity depended mainly on the meteorological conditions during the vegetation period in the given year. The years of the experiment were quite different concerning the rainfalls during the vegetation period. The first experimental year was characterised as moderately humid, the rainfall sum for the period May-September being 233.5 mm and probability level – 44.7%. In the same period of 2005, the rainfall was 455.5 mm, i.e. the season was humid and probability level was 6.4%. The third experimental year (2006) was also moderately humid, probability level being 48.9% and the rainfall sum during vegetation – 228.0 mm. The third year of the experiment (2007) was the most humid (463.2 mm) with probability level of 4.3%. However, the rainfalls were quite unevenly distributed, especially in July, when it did not rain at all. In the previous three years the rainfalls were significantly more favourably distributed and to a great degree they corresponded to the precipitation rates of the region. The yields from the different variants complied with the characteristics of the given year, the effect of the meteorological factors being strongest in non-irrigated maize and in maize irrigated at the lower rates (Table 1). In spite of all, under the conditions of the experiment, the yields were comparatively high in the years of moderate soil water supply – 2004 and 2006 (9310 and 8890 kg/ha, respectively). Although the rainfalls in 2005 and 2007 were almost equal, they were quite different concerning their distribution during vegetation. That affected directly the yields (11750 and 4800 kg/ha, respectively), the difference to the optimum irrigated variant being statistically insignificant in 2005 and in 2007 that difference was over two times bigger.

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Table 1. Effect of irrigation on the maize grain yield by variants, years and in average for the experimental period

Variant

to 2 signifi+/–D % cance 2004 1   9310 St. 100.0 St. – 2780 77.0 2 12090 + 2780 129.9 C St. 100.0 3 11330 + 2020 121.7 C – 760 93.7 4 10770 + 1460 115.7 B – 1320 89.1 5   9890 + 580 106.2 n.s. – 2200 81.8 GD P 5% = 700 kg/ha; P 1% = 1010 kg/ha; P 0.1% = 1520 kg/ha 2005 1 11750 St. 100.0 St. – 870 93.1 2 12620 + 870 107.4 n.s. St. 100.0 3 12600 + 850 107.2 n.s. – 20 99.8 4 12450 + 700 106.0 n.s. – 170 98.6 5 12230 + 480 104.1 n.s. – 390 96.9 GD P 5% = 1510 kg/ha; P 1% = 2200 kg/ha; P 0.1% = 3310 kg/ha 2006 1   8890 St. 100.0 St. – 2790 76.1 2 11680 + 2790 131.4 C St. 100.0 3 11580 + 2690 130.3 C – 100 99.1 4 10540 + 1650 118.6 C – 1140 90.2 5 10140 + 1250 114.1 C – 1540 86.8 GD P 5% = 510 kg/ha; P 1% = 740 kg/ha; P 0.1% = 1110 kg/ha 2007 1   4800 St. 100.0 St. – 6540 42.3 2 11340 + 6540 236.3 C St. 100.0 3 11160 + 6360 232.5 C – 180 98.4 4   9590 + 4790 199.8 C – 1750 84.6 5   6860 + 2060 142.9 C – 4480 60.5 GD P 5% = 510 kg/ha; P 1% = 740 kg/ha; P 0.1% = 1110 kg/ha Average for the period 2004–2007 Variant Yield to 1 to 2 kg/ha +/–D % +/–D 1   8690 St. 100.0 – 3240 2 11930 + 3240 137.3 St. 3 11670 + 2980 134.3 – 260 4 10840 + 2150 124.7 – 1090 5   9780 + 1090 112.5 – 2150

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Yield (kg/ha)

+/–D

to 1 %

significance C St. A B C n.s. St. n.s. n.s. n.s. C St. n.s. C C C St. n.s. B C

% 72.8 100.0 97.8 90.9 82.0

The grain yield from non-irrigated maize was 8690 kg/ha in average for the experimental period, which confirmed the high production capacities of the tested hybrid. By optimising the humidity factor, the yield became stable and it did not differ significantly during the four years of the study. Table 2. Extra yield and productivity of the irrigation rate

Variant

Yield (kg/ha)

Number of irrigations

1 2 3 4 5

9310 12090 11330 10770 9890

2

1 2 3 4 5

11750 12620 12600 12450 12230

1

1 2 3 4 5

8890 11680 11580 10540 10140

2

1 2 3 4 5

4800 11340 11160 9590 6860

3

1 2 3 4 5

8690 11930 11670 10840 9780

2

Extra yield (kg/ha) (%)

Irrigation rate (mm) (%)

2004 St. 0.0 + 29.9 160.2 + 21.7 120.2 + 15.7 80.1 + 6.2 40.1 2005 St. St. 0.0 + 870 + 7.4 80.0 + 850 + 7.2 60.0 + 700 + 6.0 40.0 + 480 + 4.1 20.0 2006 St. st 0.0 + 2790 + 31.4 144.6 + 2690 + 30.3 108.4 + 1650 + 18.6 72.3 + 1250 + 14.1 36.2 2007 St. St. 0.0 + 6540 +136.3 270.3 + 6360 +132.5 202.7 + 4790 + 99.8 135.2 + 2060 + 42.9 67.6 Average for the period 2004–2007 St. St. 0.0 + 3240 + 37.3 163.8 + 2980 + 34.3 122.8 + 2150 + 24.7 81.9 + 1090 + 12.5 40.9 St. + 2780 + 2020 + 1460 + 580

Irrigation rate productivity (kg/ha)

0.00 1.00 0.75 0.50 0.25

St. 17.353 16.805 18.227 14.464

0.00 1.00 0.75 0.50 0.25

St. 10.875 14.167 17.500 24.000

0.00 1.00 0.75 0.50 0.25

St. 19.295 24.815 22.821 34.530

0.00 1.00 0.75 0.50 0.25

St. 24.195 31.376 35.129 30.473

0.00 1.00 0.75 0.50 0.25

St. 19.780 24.267 26.251 26.650

The reduction of the irrigation rates and the increase of water deficit in the root soil layer led to a yield decrease. That decrease was directly dependent on the precipitation amount and distribution during the vegetation period and especially 141

between the stages of tassel emergence till milk maturity stage. In the second year of the experiment, which was the most favourable concerning water supply of the crop, the reported differences between yields of the separate variants were statistically insignificant. Small differences to the variant with optimal irrigation were established in the productivity of maize with applying 25% of the calculated irrigation rate, the losses being within 0.2 to 6.3%. Slightly bigger, although not much greater, were the losses in the variant of 50% irrigation rate applied. Those differences were statistically significant (with an exception of 2005) and they were within the limits of 1.4–15.4%. That irrigation regime is recommended when there is water deficiency. Applying 25% of the irrigation rate is practically inefficient as the yields in absolute values were close to those obtained under non-irrigation conditions. The major criterion for determining the irrigation efficiency is the extra yield and the productivity of the irrigation depth representing the extra yield obtained from 1 mm of irrigation water. Data about those indices are presented in Table 2. Figures 1 and 2 illustrate the relationship between the irrigation rate and its productivity expressed as an extra yield obtained from each millimeter of the irrigation rate. Data were presented as relative values. They varied within wide limits in the variant of the lowest irrigation rate (variant 5). This variation gradually decreased with the improvement of the water regime. Due to that, the optimally irrigated maize crop, despite the number of irrigations and the absolute irrigation rate, gave approximately similar yields. 2.3

2004 2005 2006 2007

2.1

relative productivity

1.9 1.7 1.5 1.3 1.1 0.9 0.7 0.5 0.2

0.3

0.4

0.5

0.6

relative irrigation depth

Fig. 1. Productivity of irrigation depth (2004–2007)

142

0.7

0.8

0.9

1

1.40 1.35

relative productivity

1.30 1.25 1.20 1.15 1.10

y = –0.84x 2 + 0.59x + 1.2525 R 2 = 0.9984

1.05 1.00 0.95 0.90 0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

relative irrigation depth

Fig. 2. Productivity of irrigation depth (average)

The relationship in average for the four-year period, is presented by a seconddegree curve, the averaged data obtained at R2 = 0.998. Another indicator about the irrigation efficiency is the yield–water relationship. It could be expressed in two ways: as a relation between the total yield and the irrigation rate, and as a relationship between the extra yield and the irrigation rate. The present paper presents the relation established between the total yield and the irrigation rate. It is known that it could be also presented as a square function. 1.1 2005

1 0.9 0.8

2004 and 2006

relative yield

0.7

2007

0.6 0.5 0.4 0.3 0.2 0.1 0 0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

relative irrigation depth

Fig. 3. Yield-irrigation depth (by years)

143

Figure 3 presents the summarised experimental data about the relative yield and the relative irrigation rate for the four years. Due to the specific meteorological conditions each year, there was great differentiation degree by variants that obviously decreased with the improvement of the water regime. Table 3. Yield–water relationship by years (Fig. 3)

Year 2004 2005 2006 2007

R2 0.861 0.994 0.974 0.986

Equation y = –0.2023x2 + 0.4339x + 0.7601 y = –0.0880x2 + 0.1548x + 0.9324 y = –0.1611x2 + 0.4015x + 0.7641 y = –0.4971x2 + 1.1103x + 0.4029

The equations expressing yield–water relationship by years are presented in Table 3. They averaged the experimental points at a high determination coefficient (R2 ≥ 0.86). The free term is the yield under non-irrigation conditions and it directly reflected the characteristics of the year. 1.1

1.0

relative yield

0.9

0.8 y = –0.1829x 2 + 0.4637x + 0.7237 R 2 = 0.9962

0.7

0.6

0.5 0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

relative irrigation depth

Fig. 4. Yield-irrigation depth (average)

The location of the curves towards the abscissa (Fig. 3) reflects the effect of the different irrigation regimes on crop productivity. In 2005 which was humid and with evenly distributed rainfalls, the curve is more linear, almost horizontal, that once again confirms the insignificant effect of irrigation in all the variants of the experiment. As it was already mentioned above, the precipitation in 2007 was almost the same as in 2005, the rainfalls were unevenly distributed and during the important crucial period of maize vegetation, they were lacking. Under such conditions, the effect of irrigation was insignificant and the curve describing the 144

relation in that concrete year is sloped and more curved. In 2004 and 2006 the conditions were approximately similar concerning both the meteorological factors and the irrigation regimes. That was why the effect of irrigation was similar and the curves describing the discussed relationship practically overlap. The average data for the four experimental years are presented in Fig. 4. The curve approximates the experimental data with an absolute precision at R2=0.996. Conclusions Under the experimental conditions with optimal irrigation and without fertilisation the tested maize hybrid produced a very high grain yield (over 11000 kg/ha). When water resources are insufficient, the maize in the region of Plovdiv could be successfully grown under regulated water deficit irrigation. The yields obtained when applying 25% of the irrigation rate were practically equal to the yield at optimum irrigation, representing 94–100% of it. 50% decrease of the optimal irrigation rate guaranteed the production of 85–99% of the maximum yield. Applying low irrigation rates caused a broad variation of productivity depending on the characteristics of the separate years. With the improvement of the plant water regime the variation decreased. The relationship between the irrigation rate and its productivity is a second-degree function that, under the experimental conditions, could be expressed by the equation y = –0.84x2 + 0.59x + 1.2525 averaging the experimental points at R2 = 0.998. Yield–water relationship is also adequately expressed by a quadratic equation. The equation curves for the separate years depended on the annual characteristics and they averaged the respective experimental points at a high precision. In average for the four years of the study, yield–water relationship represents a parabola defined by the equation y = –0.1829x2 + 0.4637x + 0.7237 approximating the experimental data at R2 = 0.996. References 1. Zh. ZHIVKOV: Irrigation of the Agricultural Crops at Limited Water Resources. Land Reclamation and Nature (Litva), (1995). 2. D. DAVIDOV: On the Grounds of the Relationship ‘Yield–Water’. In: Proc. of the 17th European Regional Conference on Irrigation and Drainage ICID–CIID, Varna, Bulgaria, Vol.1, 1994, 251–253. 3. Y. KIRKOVA: Water Depletion from Various Soil Layers by Some Crops under Different Water Regimes. In: Proc. of the 17th European Regional Conference on Irrigation and Drainage ICID–CIID, Varna, Bulgaria, Vol. 1, 1994, 305–314. 4. I. VARLEV, N. A. KOLEV, Y. KIRKOVA: Yield–Water’ Relationships and Their Changes during Individual Climatic Years. In: Proc of the 17th European Regional Conference on Irrigation and Drainage ICID–CIID, Varna, Bulgaria, Vol.1, 1994, 351–360.

145

5. M. ENCIN et al.: Unle aspecte ptivind irigarea pozombului; An. Jnst. Cerc. Centrale Plante Tehn. Fundulea, Bucurest, 47, 223 (1981). 6. O. YILDIRIM, S. KODAL, F. SELENAY, Y. E. YILDERIM, A. OZTURK: Corn Drain: Yield Response to Adequate and Deficit Irrigation. Turkish J. of Agriculture and Forestry, 20 (4), 283 (1996). 7. M. RUCKA: Production Increasing оf Maize for Grain Nutrition Value by Means of Irrigation and Fertilizers Application. Vedecké Prace VUZH (Bratislava), (16), (1981). 8. K. MARTIN: Ergebnisse von Feldversuchen zur Beregnung von Kornermais. Z. Bewaesserungs­ wirtschaft., 15 (2), 121 (1980). Received 27 May 2008 Revised 16 July 2008

146

Journal of Environmental Protection and Ecology 11, No 1, 147–158 (2010) Ecology

cold resistance of kohlrabi (Brassica oleraceae var. gongylodes) M. Deveci*, L. Arin, S. Polat Department of Horticulture, Faculty of Agriculture, Namik Kemal University, 59 030 Tekirdag, Turkey E-mail: [email protected] Abstract. In this study, two F1 hybrid Kohlrabi cultivars (Quickstar and Rapidstar) were tested for their cold resistance at four different plant development stages (seedling, tuber formation, tuber development and harvest stages),and at three different low temperatures (0, –5, –10ºC). By these cold temperature tests, changes in electricity conductivity and membrane permeability were examined. Trials were organised according to the randomised block design with three replications. Mean values were used in estimating vitality ratio (%). Cold tests also show that Quickstar becomes to be more sensitive after tuber development stage, but in Rapidstar, sensitivity starts by the tuber formation stage which is an earlier stage than other. Keywords: cold hardiness, Brassicaceae Family, kohlrabi, viability ratio.

AIMS AND BACKGROUND Temperature is an important ecological factor that limits agricultural production1. In areas having strong winters and late spring frosts, even the cool season vegetable production is very much restricted. As a consequence, selection and cultivation of cold resistant or tolerant cultivars has a prime importance for winter and in early spring plantations. Beyond the choice of low temperature resistant horticultural varieties, however, some convenient cultural practices improve varietal performance under adverse conditions. On the other hand, some factors such as soil fertility, short-term temperature changes and developmental period of plants at the time of frost incidence, affect the degree of cold resistance in somehow in addition to plants resistance. For these reasons, decision about the time of planting in relation to ecological conditions of the region is very important. On the other hand, varietal choice in relation to cold resistance under the prevailing ecology has a prime importance together with the factors effecting plants resistance2. Cold resistance studies are simply and best made under the prevailing open winter conditions of the region. With this way plants are established in field in autumn and their winter survival is recorded. Although the method gives most *

For correspondence.

147

reliable and possibly natural results, it is expensive, time-consuming and it may not be possible to catch extreme winters every year3,4. For this reason, this kind of studies is to be conducted in cold cabinets. Cold cabinets, developed in last decade for this purpose, are very functional with sensitive temperature and time adjustments. On the other hand, results obtained in this cabinets are strongly correlated with open field winter tests5,6. In regions where the rainfall is insufficient, especially at the main crop season, winter production may be a possible solution for water deficit. On the other hand, autumn planted plants produce a good root system and this helps a good plant development and this results in a good water and nutrient uptake. But in some regions, heavy rainfall and cold weathers restrict the plant development and crop production. In this case, cold resistance of varieties and control measures to improve the resistance of the plants themselves, takes more importance2. Kohlrabi (Brassica oleraceae var. gongylodes L.) is a member of the Brassicaceae Family, and its globular stem is mainly consumed raw or cooked as a salad. On the other hand, mineral composition of petioles are high, so, young petioles near the growing point is recommended to be consumed together with fleshy stem7,8. It is a cool season vegetable with short vegetation period, and also is an alternative vegetable crop for unheated cover production. Cold resistance of this plant is not sufficiently investigated and varietal differences for low temperature resistance are not known. For this reason cold resistance of two hybrid kohlrabi cultivars at different developmental stages was examined. EXPERIMENTAL Two F1 hybrid kohlrabi (Brassica oleraceae var. gongylodes L.) varieties, namely Quickstar and Rapidstar, were tested for their cold resistance in this study. Seeds were maintained from Sakata Seed Corporation. Seedlings were raised in an unheated glasshouse of the Department of Horticulture, Faculty of Agriculture, Namik Kemal University. Plants at four different developmental stages (seedling, tuber formation, tuber development and harvest) were tested for their cold resistance at 3 cold temperatures (Quickstar and Rapidstar). Seedlings were grown in plastic multipots each having 28 small potlets with a 150-ml volume. Black polyethylene bags of 1.5–2.0 l volume were used to grow plans for other advanced developmental periods. Peat-based soil compost (No 3) developed by Plantaflor Profi Corporation and obtained from the company distributor in Turkey, Rito Tohumculuk A. S. was used as a growing medium. Its qualifications are presented in Table 1.

148

Table 1. Some qualifications of the soil mixture used

N (mg/l)

P2O5 (mg/l)

K2O (mg/l)

pH

100–300

100–300

150–400

5.4–5.9

Elect.conductivity (µS/cm) 350

Seeds were sown in potlets filled with compost and multipot trays were kept in a laboratory room with an average 20°C, until germination. Media were then treated with Benomyl 50% against bacterial and fungal damping-off agents. Multipots were transferred to the glasshouse. Both glasshouse and open field temperatures are presented in Table 2. Table 2. Minimum, maximum and average temperatures (ºC) in open and in glasshouse

Months

October November December

Environments average temp. (°C) 14.9 12.7   8.7

open field avr. max. temp. (°C) 18.7 16.1 12.1

avr. min. temp. (°C) 10.4 7.6 3.8

average temp. (°C) 20.1 15.0 11.1

glasshouse avr. max. avr. min. temp. temp. (°C) (°C) 29.8 11.9 22.5 9.9 18.4 5.7

Plants which were transferred into the glasshouse were kept under transparent polyethylene cover to protect them from incidental temperature drops below freezing point and kept under cover until freezing tests. Determination of cold resistance. The cold resistance of the plants is tried to be determined by using three different parameters which are explained below. – The vitality ratio (%): This is a major parameter mostly used by various researchers to determine the cold resistance of the plants. Cold temperature tests were made in cold cabinets to which an automatic control device assembled. With this device, inner temperature of the cabinet can be sensitively adjusted to temperatures between +4 ºC and –20ºC with a ±0.5ºC sensitivity9–11. Plants were then taken into the cold cabinet for cold tests. Before the cabinet is started for temperature adjustment, a thermocouple was placed on the plant leaf blade to record the temperature attained at plant vicinity. At the beginning of tests, temperature of the cabinet was adjusted to +5ºC, which is the domestication temperature and kept at this temperature for 2 h. Then, by decreasing the temperature 5ºC per h, aimed cold temperatures were reached and kept at these temperatures for 2 h. Temperature of the cabinet was started to increase within the same way, by increasing 5ºC per h at the end of this period. Plants were kept in cabinets until the inner temperature equalises to the outside temperature. There was no illumination in the cold cabinet during the cold temperature application. Plants were then transferred to their places 149

in the glasshouse. A week after the cold treatments, number of death plants scored and vitality rates were calculated3,11,12. – Determination of cold resistance by electricity conductivity (dS m–1) method: It has been satisfactorily shown by many researches that resistance values obtained in cold cabinets studies are positively correlated with electrical permeability study results, thus this easy and quick resulting method can be used for this purpose5,6,13,14. Many investigators have reported that cold resistant and susceptible species can be successfully differentiated by application of this method4,9,12,15–17. The method followed in this study is the same explained by Dexter et al.13 with small difference to be adapted to kohlrabi laminas. – Determination of cold resistance by membrane permeability (nm): Chance method: This method was applied to various plants by many researchers. Leaf samples taken from each treatment were first washed with running tap water then with the distilled water, then the fresh weight of the samples was weighed on a sensitive balance and the results are noted. Then, these leaf blade samples were put in petri dishes, which contain 20 ml of distilled water and are kept in a 25ºC oven for 24 h. At the end of this period the liquid in petri dishes was transferred to the 25-ml test tubes by using pipettes. The absorption of the obtained samples were evaluated in a Hitachi U2000UV/ VIS model spectrometer in 280 nm of wavelength and the results are divided to the leaf sample weights. They were evaluated as the membrane damage in one g of leaf tissue. Here the amount of material in 25 ml liquid, is the material leaked from the damaged leaf cell membranes11,18–20. RESULTS AND DISCUSSION Vitality ratio (%). The average vitality ratios, interactions and LSD test groups on kohlrabi cultivars in different periods are presented in Table 3. If the cultivar main effect is considered, the vitality ratio of Quickstar is found to be higher than the other cultivar. On the other hand, when the plant developmental stages is concerned, the tuber formation phase has the highest vitality ratio with 64.44%, followed by tuber development period with 62.59% and by the harvest period with its minimum vitality ratio of 56.29%. At 0°C, vitality ratio is 93.33%. This means that 93.33% of the plants are remained alive. On the other hand, the ratios are 73.61% and 10.89% at –5 and –10ºC, respectively. Quickstar showed highest vitality ratio at 0ºC with 99.45% mean value. At –10ºC Rapidstar had highest damage with its lowest vitality ratio (5.50%). In this case Quickstar is more resistant to cold damage than other variety. If interaction between plant development stage and temperature is taken into consideration, plants at tuber formation stage are more resistant to cold at all temperatures. Plants are most sensitive at harvest stage.

150

Let us look at the results now from the three-way interaction. The main thing that can be easily said is that, at progressive plant development stages, cold resistance becomes to be sensitive. This is true in both varieties. And again in both of the varieties, tuber formation stage is the most resistant stage at all temperatures. If the problem is looked from varietal point of wiev, Quickstar is more resistant than Rapidstar. Table 3. Effects of low temperatures in different stages on average vitality ratios (%) in kohlrabi

Varieties and plant development stages Quickstar Rapidstar Seedling stage Tuber formation stage Tuber development stage Harvest stage

LSD

LSD

seedling stage Quickstar tuber formation stage tuber development stage harvest stage seedling stage Rapidstar tuber formation stage tuber development stage harvest stage LSD Temperature main effect LSD

0°C   99.45 a   97.22 b    2.95* 100.00 a 100.00 a   97.78 b   95.56 c    0.714* 100.00 a 100.00 a 100.00 a   97.78 b 100.00 a 100.00 a   95.56 c   93.30 d   1.010*   98.33 a    0.357*

Temperature –5°C 87.22 c 60.00 d

–10°C 16.11 e   5.50 f

73.32 f 80.00 d 75.56 e 65.55 g

  7.77 j 13.33 i 14.44 h   7.78 j

84.41 f 86.67 e 93.30 d 84.45 f 62.20 h 73.30 g 57.78 э 46.50 j

11.10 n 17.78 l 22.22 k 13.30 m   4.44 q   8.89 o   6.65 p   2.20 r

73.61 b

10.83 c

Varietal main effects 67.59 a 54.26 b 60.36 c 64.44 a 62.59 b 56.29 d   0.410* 65.17 c 68.15 b 71.85 a 65.19 c 55.55 e 60.74 d 53.33 f 47.40 g   0.583*

a, b, c, . . .: LSD groups; * significant at P