K+ HC034 SC*2 cr1. Before Acid Fowder Treatment. 1 905A 3ft72. 21.0. 17.1 270,9. 3.0. 11.0. 24.2 236.2. 640. 2 905B 29.80. 20.1. 20.5 260.1. 1.6. 13.2.
CHAPTER: IX
RECLAMATION OF SALINE-ALKALI SOILS A saline soil is one which contains high percentage of salts that can impair plant growth. An alkaline soil is one having a Ugh level of exchangeable sodium. An alkali soil may also have high pH. The limits erf salinity and alkalinity as given by USDA Laboratety (97) are: conductivity above 4 mmhos/cm. pH valtie above AS (for the saturation c x tra cta t 25°c) and exchangeable sodium percentatge (ESP) above IS. A higher percentage of indsoluble caroonaces is another problem relating to soils of the arid and semi-arid and semi-arid zones. The level of CaCO^ a t which P fixation become an agricultural problem is perhaps the margin a t which soil can be considered calcarious soil. The response of plants to saline environment is of interest to people of many disciplines. In agriculture the problem of salinity is bccomming more acute and severe every year as the exploitation of non-saline soils increases. The Cultivation of saline soils and the use of waters with relatively higher content of soluble salts must b e taken into consideration for the expansion of agriculture. The adverse effect of saline condition on plant growth and development causes considerable reduction in crop yield. W orld wide population increase of two percent per annum is a stress on existing food producing system^ In tike face o f die increasing dependence by tike expanding population on crop production it is necessary to increase area under cultivation. Therefore the reclamation of saline, alkali soils for agricultural purposes should be given priority. Chapman (17) has gleaned a substantial body of information about the factors responsible for excess of salinity in many parts of the world like frequency of tidal inundation, precipitation, effect of drainage system, soil structures, vegetation, water table, depth of salt deposits and temperature. W ater inflow and outflow from any saline/alkali area is obviously of great significance. The non judicious application of irrigation water without proper drainage practice ^ and improper drainage facilities leads to the formation of the saline soils. Besides r these factors, Bernestein (11), reported th&rt heavy fertilization intensive agriculture and glass house operation are frequent sources of salinity problem. Plojakoff-Mayber and Gale (69) explained that scanty and erratic rainfall is the main cause of increasing occurence of arid and semi-arid regions where teaching
205
**
salts by ground water does not occur. Warm weather and ill distribution of rain intensity the salt injury. Millions of hectares of land throughout the world are too saline to procure economic crop yield and more and more land becomes non-productive every year, as the non saline soils become more intensively exploited. The problem of reclamation of salme-alkali soils is multidisciplinary and has engaged attention of workers all over the world. It is a problem for engineers, chemists and agronomists. The wise use of available sources of water m il ultimately lead to better utilization of land. On the other hand, wasteful methods of irrigation and agriculture will lead to the spread of salinity and alkalinity into once fertile regions. In India, there are one crore acres o f saline-alkali soils; out of which 30 lacs acres are located in Gujarat Many factors axe responsible for formation of saline-alkali soils but they differ in different areas. (i)
In Kuteh, North Gujarat and some parts of Saurashtra, semi-arid climate is responsible for formation of saline soils.
(U) In North Gujarat, Bhai-Kantha and Nal-Kantha, Old-sea inundation has been a prominent factor, which can be cas ly traced out by fpnsidering nature of salinity of sols and Waters to be of Na-Mg-Ct-SO^ type. (iii) In areas close to sea-coast and interior upto 3-10 km, sea-salt composition is traceable close to Suart, Bulsar Dandi, Ubhrat, Kavi, Cambay, Dholeta, Bhavnagar, Porbandar, Dwaraka, Morvi, Bhachau, Mandvi, Mundra, etc. Gujarat has 1850 km long coastal area. Evca wind spread salinity is likely. (iv) In Oil-field areas close to Ankteshw&r, Navagam, Dholka, Sanand, Kalol, Mehsa&a, oil-field tube well waters are of Na-HCOj type, leading to salinization and alkalization of the soils.
'
(v) Salinity due to canal irrigation is spreading at alarming rates in Matar taluka of Kaira district Olpad taluka of Surat district and many other areas. Once canal water is available, the farmers use the irrigation water indiscriminately and within S years, there is salinity increase in soil and water logging, where sodiumisation of ~ " ’Sbil complex is high. The conventional methods existing for the reclamation of such soils ate: exhaustive tilling followed by drainage, mulching with plant materials so as to Jh«ease*fie organic miring with sand, sugar-cane waste etc. and with chemical amendments containig sulphur such as gypsum, FeSO+, A l^ O ^ y HLjSO^ followed by drainage.
208
In Gujarat saline, saline-alkali and alkali soils of different types are dispersed throughout die state. Ahmedabad is an industrial city, where we could produce w a^e sulphuric acid, altim-sludge, hydrochloric acid, sulphur and process out chemic&lslfke iron sulphate, calcium chloride. Hence beginning in 1974, the waste acid method was used for reclaiming 600 acres land in G ujarat A fter th a t using other acid producing chemicals, use of mix amendment was designed Various scientists have used different methods in this field to evolve an easy and economic reclamation. A review of the contemporary literature on the subject has been attempted here under. Kelly (37) was file pioneer to use gypsum, sulphur, sulphuric acid, iron and aluminium and farm yard manure. Gypsum has been used by several workers. Abel-Kuddons (3) tried some experiments in which gypsum treatm ent Of 2.5, 5, 0, 10, IS, 20 and 40 tons/ha was given to a sodic so il B ut under high w ater table conditions, gypsum had no effect on correcting ratios between exchangeable cations, although hydraulic conductivity were improved. Semcendyera, H.V. (81) while studying the effectiveness of die gypsum to low sodium solonetz soils, observed that calculated amount of gypsum had improved ti e soil fertility and the crop yield. A decrease in gypsum does led to decreased effects of its application. He has observed that application of 9 ton gypsum and 80 ton manure/hac. gave the best results. Abducv and Kuliev (2) reclaimed saline soils by applying 10 tons gypsum plus 40 tons/ha fram yard mannure followed by three leaching irrigations. The sofy gave better crops of rice, barley and cotton. Antipov-karataev Pak (7) have tried gypsum for reclamation of solonetzs under irrigated and unirrigated conditions. Berg and W cstrhot (10) in Netheriand studied reclamation using gypsum. The structural deterioration of soil was minimised by application of gypsum a t die rate of 5 to 7.S tons/ha which was calculated from the amount of adsorbed sodium in the soil. Bugayevskiy and cO-workers (15) fo u n d th at gypsum applied a t a rate of 10 tons/ha reduced the adsorbed Na in soil and improved the physical properties o£ the soil Buras and co-workers (16) considered application of 5 to 7.5 tons/ha of gypsum to be necessary treatm ent for reclamation of some saline lands.
Gorbunov and co-workers (26) have studied die rate of gypsum and calcitc dissolution of gypsum was slow and depended on the amount of w ater used, crystal size and speed of removal of dissolved salts. 4
4
Hamdi and co-workers (27) have gypsum as an ameliorating agent for the deteriorated soils in the United A rab Republic. S tsons/ha appeared to have no effect on reducing absorbed sodium in the s o i complex, except in soils irrigated with water having low concentration of salinity 4 tons/ha gypsum was effective against saline w ater contaiing 2000 ppm of salts and 65% sodium for the d ay loam. 'Hauser (28) has studied Afghan alkali soils and its improvement Treatment with 4 5 tons/ha gypsum decreased exchangeable sodium, increased water permeability by 24.4% and the crop yield of wheat increased by 105%. Oats increased by 35% and Barley by 70%. Heafield and Ashley (29) have studied scafloodcd soil in lidsay and Licolnshire. Application of 15 ton$.ha of gypsum ever 2 years to silty loams flooded by sea in 1953 could not stabilize soil below the cop 7.5 cm, this indicated that under drainage was necessary. Johnston (34) has studied reclamation of a saline-sodic soil in the N.K. Walini Valley, using 31 tons/ha gypsum o r 6 tons/ha sulphur. Gypsum a t this does is slightly superior to sulphur. Both the treatm ent were more beneficial titan the control. For the first sugercane crops, average yield were 100, 99 and 82 tons/ha for gypsum, sulphur and contdrl respectively. oLaktionov (41) applied 4 tons/ha of gypsum on solonetz like soil. It improves its physical properties and increases crop yield. Lopatnik (43) has studied improvement of saline soils in Chezkeslovakia jusiag gypsum. Mehlich and Tiwari (45) have discussed the role of gypsum in Agriculture in a book publishecTby Unites States Gypsum. Company, Chicago in 1974. Moustafa and Shabasi (51) reported that the physical and chemical properties of black alkali soils improved only in the layer in which gypsum was added. Hence, gypsum should be applied deeply in the soil, using a sub-soiler. Narbaev (54) has studied the source of salinazation and the order of soluble salts to be leached out, when application of gypsum was made. Obrcjanu and co-workers (56) have studied the sgcon^ary salinazation caused by rising of highly mineralized ground w ater above a critisal-leysi, allowing permanent contact of, ground watet, irrigation w ater and soil. Deepening the outlet channels contributes to preventaioiu}%
Pair and Lewis ($1) found that treatm ent of slick spots with CaSC>4 increased the intake of irrigation w ater from 0,025 cm to 0,25 cm for 25 tons/ha application. Patel, M M . and co-workers (64) have studied effects of nutrients and gypsum on crop yoelds and on reclamation of saline sodic soil. The results of field experiments showed that with the rice-wheat-rice cropping pattern, the soil came to norms! production within three seasons. Sharma and Fehrebacher (85) have studied the effect of hydrated lime and gypsum on tee leachate and sodium removal from tee B horizon of a natric soil. According to them, the effectiveness of the amendments in sodium removal from tee columns was in the order. Gypsum slurry =
gypsum
hydrated lime:
that of the rate of application was
2%
1%
0%
According to Sambur (78) on applying gypsum tee yields of sevaral crops were increased on solonchakous but on the soda-solonetzed annual, application of gypsum was completely ineffective. Sambur and Kovalenko (79) suggested te a t gypsum increases yields on less wet soils but decreases on very wet soil. Sen and Rewari (82) suggests 12.5 tons/ha gypsum to improve a sandy saline so i. Sindhu and Cornfield (90) studied effect of reclamation treatments (gypsum). However a dose of 10-12.5 tons/ha is common because gypsum is solubel to the extent 0.25% in water. This low solubility requires a high amount of water. Hence the method may be restricted to (i) high rainfall areas and (ii) canal irrigation area). Shainbcrg, Keren and Frankel (89) have studied reclamation of sodic soil using gypsum and calcium chloride amendment. They tried to measure tee effect over long period. O ster and Frankel (58) have also studied the recaimation of sodic soil. Jerry, Jerrell and Devitt (32) have discussed the recaimation of saline-sodic soil by teaching. In Gujarat the climate is semi-arid in 60-70% areas hence an alternate method was to be searched for. Sulphuric ad d has been used for reclamation of saline-alkali soils by many woken. Abduev (1) used gypsum, its combination with manure, organic mineral waste, and acidifier (wastes from oil refineries and chemical plants). He also used sulphuric acid in varying doses from 10 to 80 tons/ha. Most efficient and economically advantageous methods of improving hardly reclamablc soionetz were obtained.
Alawai, Strohldn, Hanlon and Turner (6) studied die effects of sulphuric ad d and gypsum on soil properties. They concluded th a t sulphuric a d d was superior to gypsum in terms of yield increases and soil improvemnt Berezin and co-workers (9) have shown that advantage of soil addificadon by sulphuric a d d lies in the accelerated dbplacem nt of exchangeable sodium during the first two years, whereas the advantage of gypsum application becomes apparent in the third-fourth year; thus gypsum is dow er tan sulphuric add. Boras (12) used a method for the reclamation which involves neutralization of soil solution by dilute H^SO^ o r F cS0 4 and removal of exchangeable sodium by use C aS 04 and subsequent leaching. Chena (20) earned out laboratory studies for reclamation of saline-sodic so il Sulphuric a d d alone removed the sodium almost twice as rapidly as gypsum alone did. Miyamoto and Rayon (48) suggested the use of H^SO^ for the treatm ent of ammoniated irrigation waters. Ammoniated w ater cause predpitaion of CaOQ^ and increase in exchangeable Na and NH4, thus causing low infiltration in soils. H ^S04 application reduced Ca precipitation and exchangeable Na by neutralising OH produced by NH^ and consequently preventing dedine in infiltration rates. Kovda (38) has studied reclamation of alkaline, soda saline soils. H e reports that in order to ensure permanent improvement of soda soils application of large quantities of gypsum (4 0 - 9.0 tons/ha), sulphur 1-2 tons/ha and sulphuric a d d are required. Drainage is uecessaty besides using chemical treatments. Melkouyan (46) has reported redam ation of saline-alkali soils of A rarat plains by addification. He has used 2% sulphuric ad d for treatm ent Oganesyan (37) has reclaimed Solonchak* solonetzes and moderately saline solonctz soils by applying sulphuric ad d after sowing. He has sprayed 0.5% H ^S04 a t 13 tons/ha and therby enabled the seedlings of wheat to emerge. The improvement in chemical properties had extended down to atieast 100 cm. Overstreet, Martin and King ($9) have tried gypsum sulphur and sulphuric a d d lo r '. reclaiming alkali soils. The superiority o f sulphuric a d d treatm ent was confirmed in second series of trails in which application of 7.12 and 3.33 tons/ha were made. Overstreet and co-woriters (60) found th at 4 tons/a of C aS 04 or 3.S tons of H S 0 4 were maximum requirements for redam ing a fine sandy loam.
210
Petrosian and Avundjian (68) have studied chemical reclamation and effect on physical and water physical properties of soda saline soils in ProArax low land. The acidification with sulphuric acid affected partial neutralisation of alkalinity and significant decrease in BSP: the Ca+ * ions of die newly formed gypsum release the exchangeable sodium. The permeability o f soils increases very much. Prather (71) used H ^ 0 4 as an amendment for reclaming soils high in Boron. Prather and co-workers (72) have studied reclamation of sodic soils using three chemical amendments C&S€>4, CaCl2 and H^SO^ As single amendment H^S04 was more effective than C aS04> Combining either CaQ^ or H^S04 with CaS04 appreciably reduced the time and leaching needed to achieve reclamation, compared with CaSt>4 alone. Shanna and Mehrotra (86) used waste H jS0 4 on saline soils of Kanpur and compared the results with gypsum treatment Sharma and co-workers (87) carried out reclamation with gypsum and and suggested that die best improvement taken place in case of H^SO^ Tyulenina and Fomina (96) have suggested chemical improvement of solonetzes using 54% HjSO f The yield of grass from plots treated with H^S04 was 523-63 quintals/ha h itler than that of control. As early as 1915, Kelley (37) used pure HjjSO^ But with availability of waste sulphuric acid from chemical industry, synthetic fibre industry, dye stuff industry etc and with the availability of plastic ware, waste acid method has established its rote as quick and superior method to gypsum method. This is used in Arid regions of Arizona by Miyamoto and Strohlcin (49) and by many Russian scientists. Of course waste acid spray on a small scale is difficult to handle. Hence add formers fulfil the same role with a little decrease in quickness and efficiency. A dd formers like sulphur, iron-sulphate, aluminium sulphate, pyrites are used with advantage in calcareous sodic soils. Acevedo-Ramoss, Bonnet and Ortiz Velez (4) reclaimed saline sodic soil with 25 tons/ha bagasse with or without sulphur and GaC^ at the equivalant of 10 tons/ha sulphur. Araay (8) has discussed the principles for reclamation of saline soils by using sulphur mineral adds, hydrolytically dissociating salts [Al2 ( S O ^ F eS04, Fe^S] gypsum, lignite and sand. Bottini and Lisanti (13) improved the permeability of soil whose p ly&s above 9.0 aod which contaied N ,20 0 3 by aaing JcSO, aad CaSO,. With FeSO,, Bocculatbn 211
%
*
appeared more vigorous and pH was reduced a greater extent than with CaSO^. Branson and Firemn (14) reclaimed an impossible alkali soil Paloverde valley in California. H ie most effective treatm ent consisted of the application of C aG ^ Following C aQ 2 in effectiveness were th e acidifying amendments viz sulphur and ferric sulphate. Gypsum increased yields to the some extent as die acidifying amendments did, b u t only after a much longer period of leaching Treatments which supplied litter o r no soluble calcium were not effective. These studies indicated that alkali soils in other areas could be reclaimed by applying known treatments. Gidnavar, Gumaste, Krishnamurthy (24) have studied effect of amendments on the properties of saline alkali soils of Nargund (Dharwar district). Sulphur was applied a t the rate of 150*300 kg/ha with o r without form yard manure on saline-alkali soil (pH > 9.0). Infiltration rate of treated soil was increased. Heckel (30) has studied improvement of alkali soils with C a Q y , C aS 04, soluble iron, aluminium salts, sulphur and lignite. Kacar and Akgul (35) have studied influence of heavy dressing of sulphur on availability of soil phosphorous in alkaline calcareous soil. 250-800 kg/100 sq. m t sulphur was applied to calcareous sandy loam soil, phosphorous P isotpe was used and it was found that sulphur increases the availability of soil phosphorous in alkdine calcareous soil. Laktionov (42) used FeS04 to improve the physical properties of solonetz soils and obtained increased yields of winter wheat and sugar beet and the increased s?gar content in the b e e t Manukyan (44) has discussed chemical amendments HjSO^, H O , HNG3 and FeSOj. Tha salt content was reduced below the toxicity level and the soil was desolonetezized. The pH changed from 9.5 to 7.6 Ferrous sulphate is preferable for improving sodic solonchak-solonetzes. Nurijantan and Khizantsian (55) have studied the efficiency of chemical reclamation of soda salinized soils against the background of d o se horizantal drainage. The redam ation is carried out with FeSO^ in powder form. It was followed by desalinization of recaimed soils a t depth of 1 meter. From die estimated 1 meter fyyer, th$ alkaline reaction has been neutralized cpmpletely. J h e active sodium has been replaced by calcium.
212
Pak and co-workers (62) have recaltmed soloaetz in USSR using gypsum, CaCb and byproducts e.g, ferric sulphate and of the chemical industry. There are about 100 million hectares of soloaetz soils in USSR. 10% of rise above soils suffer from soda salinization, Petrosian (66) suggets that waste HJSO^ and FeSO^ are the most efficient amendments for improving soda-saline soils. The ameliorative influence can be observed in a very short time. Applying H^SO^ or FeS04 causes neutralization ol the allkaline reaction and desalinization of the soil, sharply increasing infiltration rate and permeability. Poonia and Bhumbla (70) have studied the effect of H G and AL^SO^j on yield of dhaincha (sesbania aculeata). The extent of yield enhancement by those amendment was in the decreasing order.,
Ha > h ^o 4> Rai and co-workers (74) have reclaimed calcareous saline-alkali soils using low grade pyrites applied at 4 tons/ha. containing iron sulphide and sulphur. Sandaoval and co-workers (80) suggested that crop yield tended to increase with both sulphur and gypsum amendments on the IS cm plowing depth., Shchurina and Kurbatov (88) have stnidcd properties of a solonchak solocetz during reclamation by application of gypsum. H^SO^ and FeSO^. They observed that the mlnerological composition of rite water-peptizable clay fraction was unaffected by the chemicals. Szabollcs (92) presented a review on the reclamation of solonetz soils in different European countries. Szekely and Pantos (99) have discussed the possibility of reclaiming alkali soils with coal slag and blue dust and compared it with results by CaSO^, H^SO^, A12(S 0 4)3. Taha and co-workers (94) have reclaimed alkali calcareous soil in Egypt using gypsum and sulphur. Sulphur was found to give best results for these alkali soils. Taskaeva (95) has studied the effect of by-products of the lacquer industry containig 59% dcrric sulphate in increasing the fertility of solonetzes. Ryan and Tabbara (77) have observed that Urea phosphate improve water infiltration and permeability in tails whose structure'is adversely affected by excess, of Na, The improvement in infiltration race was probably due to H^PO^ solubilizing CaCOj for exchange reactions of Ca + + with soil N a+ . The use of urea phosphate and other acid fertilizer in improvement of problem soil have also been studied by
213
>
Mikkelsen and Jarrell (47), Gregory (25), Mortvcdt and Kclsoe (5), Ryan end co-workers (75, 76), Yadav, J.S.P. (99) in an exhaustive review paper presents information on different methods of reclamation and management of salt affected soils in India and abroad. The chemical methods deal with use of gypsum its dose, size of particles, depth of application and frequency of application; C a Q ^ Sulphur; pyrites; phosphogypsum; sulphuric add; lime and pressmud. Calcium chloride has been used by some workers. Laboratory studies performed by Doering and Willis (2) showed th a t hydraulic conductivity of sodic strip-mine soil is maintained a t an acceptable level by leaching with high salt water and that soil materials can be reclaimed using highly soluble Ca sline. C aQ ^ solutions stronger than 0.5 N leading to satisfactory reclamation. Mozhciko (52, 53) has studied chemical reclamation of sodic solonetzes by application of gypsum and C a d y Application of gypsum was most effective in shallow solonetz soils, but it was less effective in deep solonetz soils and in alkali soils. Efficiency of C aC ^ application in the first year was hiigher than that of gypsum. The combined application of gypsum and CaO^ was rather promising in speeding of the reclamation. He reports the use of Q C L, for chemical reclamation of solonetz coils of Ukrainian S.S.R. field and pot experiments showed that of CaC32 was effective particularly for soda solonetzes. Qadar and co-workers (73) have studied the effect of calcium salts on induction of sodicity resistance in rice. The rice seedlings treated with 0i5 and 1% solution of calciium chloride, 1 and 2% solution of calcium nitrate, for 16 hrs transplanted in the sodic soil, increased the grain yield by 19 to 48%. Of all the treatments, 1% C a d 2 solution treatm ent was the b est Vasil’Chikova (98) have made comparative investigation of gypsum, FeSO^ and C a d 2 on soda solonchaks. FeSO^ was found to be the best, next comes C a d 2 and the last gypsum. C a d 2 is superior to gypsum (CaSG^, 2H20 ) because of its high solubility. The filters like molasses, petrol mud, press mud, sewage-sludge, rice-husk, Deem leaf, krillium sand improve soil structure on mechanical principle. The soil containing filters have improved percolation rates. However, saline-alkali land reclamation is not only a chemical problem. I t has engineering and hydrologic (drainage) and agronomic aspects to be taken care of.
214
Improvement by drainage has been discussed by many workers. Atteman and Vigneron (5) have studied in France the sub-surface drainage as a means to re d a m saline and alkali soils. Dhruva Narayan (21) has discussed engineering aspects tor reclaiming alkali soils. The role of sub-surface and surface-drainage has been discussed and hydtologoc factors have been evaluated. Framji (23) has reviewed die w ater logging and drainage problems and their solutions in India. Research needs for obtaining scientifically precise antiwatcrloggiig measures and their design criteria have been indicated, but it is concluded th at with the modem methods of Systems Approach it should be possible to evolve, without waiting for research results, the optimised measures for meeting the requited conditions of integration of groundwaosr and surface w ater uses, of irrigation and drainage networks for stable groundwacer conditions a t the required degree of relief and for ensuring permanent irrigated agriculture. Jaiswal and Dhuvanarayan (31) have studied the design of sub-surface drainage. The design is based on the field data of HC and the dranaige requirement on the basis of rate of water table fluctuation and infiltration rate, and depth of the impermeable layer. Kovda and co-woricers (40) have published an international sourcebook covering die aspects of irrigation drainage and salinity. Kovda and Egorov (39) discussed the problems of applying drainage as an important measure against the salinization of irrigation soils. Penskoi (65) has determined the distance of effective functioning of drains. The distance of 150 mts. appears to represent the limit of effectiveness of drains on the water salt cycle in saline soils. Chaudhary and co-workers (19) found that use of green manure, dhaicha caused better aggregaion of the soil when used with gypsum and paddy crops. Chaudhary and co-workers (IS) have also investigated the role of Suaeda fructicosa in relamatioc. of saline and alkali soils in W est Pakistan plains. It takes three years to reclaim the soils. Johnson (33) has studied land reclamation in Saskatchewan (Canadian Land Reclamation Association, Regina). He stressed on the need for continous cropping or permanent vegetation on saline soils w iti emphasis on tolerant forage crops such as tall wheat p a ss, slender wheat grass, wild rye cv. A ltai, Lucerne and sweet clover. Kanwar, Bhumbla and Singh (36) have studied reclamation of saline and sodic soils in Punjab. They have used dhaicha as green manure and gypsum and press mild as chemical amendments. Palkhiwala and Shah (63) have suggested plantation of Prosopis Julifiora, use of gypsum, petroleum mud, resins and lime sludge jo reclaim saline-alkali soils of Saurashtra.
215
Petrosian (67) kave studied the role of lucetenr in reclamation of salini2ed se ll According to him due to lucerne growth there is decrease in capillary rise of mineralised groundwater. Shah and Vora (83) suggest growing c f prosopis juliflora for improving saline soils. Yadav, Pathak (100) studied five saltne alkali soil profiles one each from Andhra Pradesh, Madhya Pradesh, Maharashtra, Rajasthan and U ttar Pradesh. All were calcareous and deficient in organic matter, nitrogen and available nutrients. Various forest speies viz. Acacian Arabics, ATbizzia procera, Azadirachta indies, Prosopis Juliflora, Prosopis spicigera, Eucalyptus etc. have been suggested for reclamation. United States Salinity Laboratory (97) has done excellent services to farmers resid ing in slaine alkali land. All the chemical methods discussed above have been suggested by U.S. Salinity Laboratory. Szabolcs (91,92) has also made a review of work on reclamation of saline alkali soils in many European countries and USSR Shah and co-workers (84) suggested first the use of from dairy industry for the reclamation of saline and alkali soils. In the first successful reclamation tesi: in die field of Patan and Zilia (North jGtijarat) the waste from Dudhsagar dairy, Mehsana urns used. Later ad d waste from detergent slurry industries were also tried. The percentage composition of the a d d waste from die former sources was 1.
Sulphuric a d d
60 - 65%
2.
Milksoilids
5%
3.
Remaining
W ater
While that from the latter was 1.
Sulphuric ad d
60 - 70%
2.
Alkylbenzene sulphonate
4-5%
3.
Remaining
W ater
In the present work redam ation of saline alkali soils by ad d powder method (mixed amendment of iron Sulphate, Sulphur, Gypsum and Humic a d d ) was studied at few places in G ujarat Permeability of air and w ater can be improved by chemical amendments which replace sodium in the soil complex by calcium. The higjh ESP of alkali soils can be lowered down when Ca+ + ions from CaCOj are generated by interaction with addic material. Favourable results have been obtained within 15 to 20 days after applying the ad d powder method on field. A t the same time this acid-powder method is quicker and cheaper. It also controls pollution of water streams because it uses industrial waste-add.
216
Experiments of reclamation on field were conducted by acid powder method on saline-alkali soils of Varana, Dhudhakha, Boratwada and Chanasma. The constituents of acid-powder (pH = 2.0) are 32% iron sulphate (waste sulphuric ad d of induatries was fixed as iron iron sulphate by reaction with iron). 32% industrial waste sulphur, 32% gypsum and 4% humic acid (prepared by the reaction of jaggery oil seed cake). This a d d powder was applied a t a levd of 2.5 tons/ha and IS cm of w ater was put on the land. In the present work chemical amendments (i) Iron sulphate (ii) Gypsum (iii) Sulphur were mixed in equal proportions and applied a t 1 ton/ha dose. The results have been presented in Table No. 9.A1 to 9.A4, 9.B1 to 9.B4, 9.C and 9.D
217
TABLE: 9.A1
(I) CHEMICAL ANALYSIS OF SOIL SAMPLES FROM VARANA (SATURATION EXTRACT ANALYSIS)
Saturation Extract Determination Meq/Lit EcxlC? at Sr. No. Sample 25*C No. mhoifem Ca+2 Mg+2 Na+ K + HCO3'1 SO4 2 O '1
SAR
Before Acid Powder Treatment 1
901A
6.82
&4
10.2
53.2
0.6
11.1
3.0
564
iai
2
901B
7.68
7.2
6.6
61.1
1.1
13.1
5.8
62.2
23.2
3
901C
5.92
62
88
49.1
Tr
12.1
4.6
441
17.8
After Add Powder Treatment 1
901A
3.38
mo
4.0
mi
Tr
3.7
10.8
21.4
7.3
2
901B
3.80
m2
3.8
27.2
0.3
65
11.4
21.5
m2
3
901C
4.01
&S
6.7
27.3
Tr
1.6
13.5
261
10.4
218
TABLE: 9.A2
(I) CHEMICAL ANALYSIS O F SO IL SAMPLES FROM BHUDKAKHA (SATURATION EXTRACT ANALYSIS)
EcxlO5
Saturation Extract Determination Meq/Lit
at 25°C Sr. No. Sample No. mhampl< No. No. &P.
A C Ur
CV A HAM n?A R l P IA M C\
ILAIJriAPi iilyUiLlli lUWoj
Soil Determination Alkaline PH T.RC Naas meq/100g. a.'Tpr' erth 7V1LJL* of mcq/ &£. 100* Ca+2+M g+2j K -fl Na+1 (ESP) Carbonate % Before Add Powder Treatment 19.1
13.2
0.7
5.5
286
3.9
38
as a3
34.3
24.1
0.7
iai
29.2
5.6
59
8.6
2&4
221
07
5.8
20.4
49
1
901A
40
2
901B
3
901C
AfterAcid Powder Treatment 1
901A
40
7.1
27.1
24.8
Tr
24
ao
1.2
2
9WB
40
7.4
19.9
mi
0.3
24
124
4.3
3
901C
51
ai
23.1
19.2
0.4
3.5
15.1
4.4
222
TABLE :9.B 2
(II) CHEMICAL ANALYSIS O F SO IL SAMPLES FROM DHUDHAKHA (DETERMINATION O F EXCHANGEABLE IONS)
Sr. lample No. No. SLP.
Soil Determination Naas Alkaline PH T.&C meq/lOOg. erth of Iuvt| / SB. 100* Ca+2+Mg+2 K + l Na+1 (ESP) Carbonate % Before Add Powder Treatment
1
902A
37
&1
20.2
16.5
0.4
27
13.5
29
2
902B
41
A3
27.4
19.9
0.5
63
24.2
3.1
3
903A
51
8,2
43.5
27.4
07
15.8
37.1
29
4
903B
47
ao
447
26.3
03
iai
401
3.4
AfterAdd Powder Treatment 1
9G2A*
35
7.3
19.4
* 17.2
Tr
1.7 —&J-
1.4
2
902B’
. 41
7.2
24.9
21.8
Tr
3.4
128
26
3
903A’
51
69
26.5
246
TV
27
100
1.5
4
903B*
47
7.8
309
27.4
Tr
45
141
3.2
223
TABLE :9.B 3
(II) CHEMICAL ANALYSIS OF SOIL SAMPLES FROM CHANASMA (DETERMINATION OF EXCHANGEABLE IONS)
Sr. iampk SLP. No. No.
Soil Determination Alkaline Naas T.EG meq/lOOg. %TEC «th meq/ 100* Ca+2+M g+2 K + l Na+1 (ESP) Carbonated
PH of aE
Before Add Powder Treatment 1
904A
48
at
44.9
37.7
Tr
64
14.6
12.6
2
904B
38
7.4
46.3
42.7
0.3
3.8
62
0.9
3
904C
37
7.9
3ai
33.9
03
3.8
9.9
63
ampi< No. No. &P.
OF
EXCHANGEABLE IONS)
Soil Determination PH TEC Naas AlkaHne meq/lOOft q C iD r of IIXC€| / ertfa S.E. 100ft Ca+2+Mg+2 K + l Na+1 (ESP) Carbonate % BeforeAcid PowderTreatment
1
905A
50
8.8
41.1
19.2
1.8
20.1
4a7
3.6
2
905B
52
&9 43.9
0.8
226
51.4
26
3
906A
56
&1
46.6
ms mi
16
26.6
55.3
43
4
906B
55
ai
39.9
1&5
2.4
lft9
48.4
41
AfterAcid Powder Treatment 1
905A’
42
7.1
27.4
24.1
0.3
3.0 11.2
1.6
2
905B*
50
7.3
36.9
27.9
0.4
a
6
23.1
21
3
906A’
53
7.1
35.4
27.8
0.6
7.1
19.9
20
4
906B*
55
7.6
26.2
17.0
21
7.6
29.4
3.9
225
TABLE 9.C (III) MECHANICAL ANALYSIS O F SO IL SAMPLES Sr. No.
1
Place of Sampling
S
iampleNo. C’oarse . Btfois- r ?in« Silt □ay GaCOj Qcgmatter and Sol. tare ota! kind Depth Salts Sand *
VARANA
Before Acid Powder Treatment 11.6 64.2 7.1 101 901A 3.1 (0-r) ' 901B 5.0 7.8 59.8 7.5 15.2 901C
