Ethnobotanical and ecological approaches for conservation of

Ethnobotanical and Ecological Approaches for Conservation of Medicinal and Aromatic Plants C.P. Kala Ecosystem & Environment Management Indian Institute of Forest Management P.B. No. 357, Nehru Nagar, Bhopal - 462 003 Madhya Pradesh India Keywords: traditional resource management, sacred species and grove, sustainable harvesting, biogeographic zones, protected areas Abstract In the recent century, the close relationship between ethnobotany and economic development has raised global concerns towards shrinking populations of medicinal and aromatic plants (MAPs). With the globalization and advent of commercial interest, the ethnobotanical knowledge on useful MAPs is being transformed into commercial gains, whereas, the traditional practices and methods developed by local people for sustainable harvesting and conservation of MAPs are generally overlooked. Notwithstanding, the causes for declining MAPs are not all anthropogenic. The natural factors, such as, habitat specificity, narrow range of distribution and low population size of MAPs, including herbivores and seed predators could substantially limit the MAPs in any given area. The present paper, therefore, attempts to explore the various ethnobotanical and ecological approaches for conservation of MAPs. INTRODUCTION Worldwide, in the present century, there is a growing recognition of plant-based medicines and perfumes because of substantial values and traditional knowledge associated with plants that help in producing herbal drugs and perfumes. According to an estimate of the World Health Organisation (WHO), almost 80% of the human population still rely on plant based medicines despite the heavy flow and demand of synthetic drugs in the market. At present, the business in medicinal plants has reached upto US$ 14 billion per year, which is growing at the rate of 15 to 25% annually, and according to an estimate of the WHO, the demand for medicinal plants is likely to increase more than US$ 5 trillion in 2050. Similarly, the cosmetic industries are using plants heavily in their products, which include extract of several medicinal plants (Lange, 1997; Kala, 2005a; Kala et al., 2006). Apart from health care and perfumes, the medicinal and aromatic plants (MAPs) are mainly the alternate income generating source of rural and underprivileged communities. The instant rising demand of MAPs is unfortunately creating heavy pressure on some selected high-value MAP populations in the wild due to unsustainable harvesting (Kala, 2000). Hitherto, an estimated 4,000 to 10,000 species of medicinal plants exclusively have reached a critical level of potential local, national, regional or global extinction, with subsequent serious consequences for livelihoods, economies and health care systems (Hamilton, 2004). The causes for the declining population of MAPs are not all anthropogenic, many MAPs have slow growth rates, low population densities, narrow geographic ranges, habitat specificity, low fertility and high mortality (Kala, 2005b); hence the additional anthropogenic pressure may enhance the rate of their extinction (Jablonski, 2004). In view of the wide acceptability of plant based products and ongoing pressures on existing populations of MAPs, it is imperative to explore their viable and possible conservation strategies. Further, being a vital income generating resource for the development of various social groups including disadvantaged communities, there is an Proc. 4th IS on Breeding Research on Medicinal and Aromatic Plants (ISBMAP 2009) Eds.: Baričevič et al. Acta Hort. 860, ISHS 2010

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urgent requirement of long-term sustainability of MAPs. The present paper, therefore, attempts to explore the various ethnobotanical and ecological approaches for conservation of MAPs. ETHNOBOTANICAL APPROACHES Historically, the geographic barriers played a major role to weaken the linkages and localized distribution of ethnobotanical knowledge developed by various ethnic communities on the use and management of surrounding biological resources. With the globalization and advent of market forces, most of the useful ethnobotanical knowledge including knowledge on MAPs developed by various groups of people has been transformed into commercial gains. Within China, before the 1990s, more than 70 plant species were exported from Southeast Asian and African countries for preparing traditional Chinese medicines. The continuous exploration and research on substitute native plants based on ethnobotanical knowledge has led to a decline in this figure from 70 plant species to 30 species (Pei, 2001). However, in most parts of the world, the indigenous practices adopted by the local communities for conservation of useful ethnobotanical species have been overlooked with due course of time (Sajwan and Kala, 2007). Disconnecting the use of MAPs from their indigenous conservation practices has become one of the causes of concern because of their rapid decline even in the wilderness areas. The indigenous communities have not only co-evolved with the surrounding environmental conditions but also they have actively maintained it in a diverse and productive state on the basis of several kinds of beliefs and practices. Since the use of MAPs is deeply rooted in their social and cultural fabrics, the sustained availability of these resources was the necessity of these communities. Such necessity had made them to evolve a system having some customary laws and practices, which in the long run might help to conserve the useful ethnobotanical species. Some prominent live examples of ethnobotanical ways of conserving MAPs still exist, which include the philosophy of sacred groves, sacred species and sacred landscape. Sacred Landscape Historically, the Greek and Roman landscapes were dotted with several sacred places, which usually contained groves of trees, and Romans often had personified these trees as the ‘Forest King’ (Hughes, 1990). In the Indian subcontinent, traditionally, many mountain peaks and wilderness areas are venerated as the haunts of deities, demons and fairies. In India, many mountain peaks, such as, Nanda Devi, Nilkanth, Gauri Parbat and Trishul symbolize the Gods and the Goddesses and hence people worship these majestic peaks. The land, tributaries of many sacred rivers and various natural and man-managed ecosystems, all together represent a set of interconnected ecosystems. The Ganga is venerated a holy river by Hindus, which originates from the Gaumukh glacier of the Himalaya and wherever the Ganga traverses that landscape is also considered sacred. The sanctity of these landscape helps in conservation of biodiversity including MAPs. Sacred Grove The evolution of the sacred grove’s concept is mainly based on the strong interaction of society with the surrounding forested areas, which in the long run secure the group of species and natural habitats. The historical evidences suggest that this concept of conserving species has been adopted by various communities worldwide, such as, aboriginals of Australia, Caucasus Mountains community, ancient Slavic people, German tribes (Tokarev, 1989), Greeks and Romans, Kikuyu of Africa (Hughes, 1990), and Mbeere tribe of East Africa (Gowda, 2006). Before the spread of Christianity and Islam the sacred groves covered much of the Middle East and Europe. The concept of sacred grove for conservation of species is so much important that it still persists in many parts of Asia, Africa and Mexico (Gadgil et al., 1993). More than 130 major ethnic communities live in the eastern Himalayan region of India (Kala, 2005c), and it was not 20

uncommon in the past to locate one sacred grove maintained by each village community. At present, when in most parts of the world the forest cover and the biodiversity are dwindling; these sacred groves are increasingly being recognized as the stronghold for precious biological species including MAPs. Sacred Species Several important MAPs are symbolized as sacred species. Many sacred MAPs have low population size, Saussurea obvallata, Saussurea simpsoniana, Angelica glauca, Angelica arch-angelica, Nardostachys grandiflora, Zanthoxylum armatum, Santalum album, Ocimum sanctum, for example. The multiple values and high importance of these species have made the people to link these species with religion in order to protect them from overuse and exploitation (Kala, 2006; Gowda, 2006). Many plant species are medicinal as well as religious and aromatic, and many MAPs are worshipped as a symbol of local gods and goddesses. Hence, there is a general fear in indigenous communities towards the over-exploitation of such plant species (Kala, 2005a). Such a traditional belief in the society is a way of conserving the useful natural resource, which needs to be kept alive in order to sustain the MAPs populations for future generations. There are many examples of associating useful species with local deities in the Indian sub-continent. Aegle marmelos is one of the important MAPs, which is used in various indigenous systems of medicine in India, China, Burma and Sri Lanka (Kirtikar and Basu, 1984). More than 66 ethnobotanical uses of Aegle marmelos are reported within India, of these 48 uses are related to medicinal and aromatic purposes (Jain, 1991; Kala, 2006). Its aromatic cold drink and jam has high demand. Since Aegle marmelos has quite a high number of uses and its subsequent over-exploitation has led to associate this species with the Lord Shiva and goddess Lakshmi by Hindus so that people can pay regard to this important useful plant species and avoid its destruction. The traditional healers also avoid disclosing many medicinal properties of this tree in view of reducing the overwhelming pressures of its collection (Kala, 2006). While transferring knowledge to the next generation, many herbal healers take an oath from their disciples not to misuse the knowledge on medicinal plants. Earlier, such conservation oriented practices of important ethnobotanical species was enforced by traditional beliefs and customs, which are still alive today, though in fragments, on the name of their traditional cultures. ECOLOGICAL APPROACHES MAPs and their supporting natural systems may be sustained by dynamic ecological patterns and processes. The MAPs and their associates evolve together over thousands of years, which made them to adapt for a particular climatic condition. Some MAPs may affect communities disproportionately to their abundance and biomass, while some survive only in the presence of other symbiotic species. Besides, the loss of habitat can reduce the survival rate and viability of MAPs and too much disturbance can lead to ecosystem collapse. All these factors are interlinked and in some way or another helps in the survival of the species in its natural habitat (Wallington et al., 2005). The various ecological characteristics such as climate, soil, habitats, geography, phyto-sociology, etc., are important and decisive factors for conservation of MAPs. The distribution of MAPs, generally, varies with biogeographic zones. Some of the MAPs have wide geographic range and adaptability hence they inhabit in more than one biogeographic area while others have a narrow range of distribution and are even endemic to a particular locality (Kala, 2005b). Coptis teeta, endemic to eastern Himalaya and Declapis hamiltonii endemic to south India are the examples of this fact in the case of medicinal plants. Many medicinal plants, such as, Saussurea obvallata, Taxus baccata, Dactylorhiza hatagirea, Picrorhiza kurrooa, etc., have habitat specificity. Further, if such species are domesticated out of their natural habitat, the natural efficacy in the forms of medicinal and aromatic properties got diminished (Kala et al., 2006). It is important to conserve such species in their natural habitats by means of in situ conservation. Further, conserving representative areas of MAPs in a biogeographic zone facilitates conservation 21

of the majority of the species. The anthropogenic pressures, mainly in the form of human-induced landuse change and overexploitation of MAPs for commercial gains, have the largest effects on MAPs survival in the natural habitats including biodiversity (Kala and Shrivastava, 2004; Wallington et al., 2005). To minimise the impacts of such disturbances, the philosophy of setting a protected areas network has been brought in. Realizing the need of conservation as well as the utilization of bio-resources, the legal status of protected areas varies with national parks, sanctuaries, reserve forests and biosphere reserves. The legal provisions that do not allow harvesting MAPs from the national parks and also regulate their harvest from the sanctuaries mainly help in conservation of these important species including rare and endangered categories. Apart from in situ conservation approaches (e.g., national parks, wildlife sanctuaries, biosphere reserves, reserve forests and biodiversity hotspots), the ex situ conservation practices by developing nurseries, herbal gardens, botanical gardens, seed banks and tissue culture play an important role in saving the MAPs. Studies conducted in the Himalayan region have claimed that the population of rare and endangered MAPs was higher in the protected areas compared to the adjacent unprotected areas (Kala, 1998, 2005b). The heavy livestock grazing is mainly considered an important factor for the loss of MAPs, especially of threatened categories across the globe. This may result in habitat alteration, habitat destruction, change in plants assemblages and composition, and providing space for invasive species (Kala, 1998, 2004; Kala and Shrivastava, 2005). It is also presumed that MAPs have different responses to harvesting by humans and browsing by livestock. Therefore, conservation tactics may deal accordingly. In order to mitigate the pressure of livestock grazing rotational grazing is recommended, apart from managing the herd size of grazers and browsers. In order to conserve species including MAPs by means of ecological approach, it is necessary to monitor the changes in ecosystem and abundance of the concerned species in such ecosystems (Gadgil et al., 1993; Folke et al., 1998). Some MAPs grow in specific habitats and microhabitats hence such habitats must be protected. If the species holds low abundance and density, the total protection may be granted to such species. Besides, the vulnerable stages of the life history of important MAPs may be given protection for their survival. The temporal restrictions may be imposed on the harvesting of MAPs. The different ecological processes at multiple scales are required to be assessed and managed for conservation of MAPs. HARVESTING MAPS: ETHNOBOTANICAL AND ECOLOGICAL OUTLOOK Over years of observations, the indigenous communities have developed their own knowledge on the sustainable harvesting of MAPs, which still remains an important instrument for their conservation. In most of the communities, the traditional herbal healers mainly adopt the selective harvesting of medicinal plants, which depends on numerous factors (Kala, 2005a, d). In India, the traditional herbal healers mostly used to collect mature plants. Underground plant parts (root and rhizomes) of perennials were generally gathered after 2 or 3 years of growth. Tubers and bulbs of the annual species were collected at the end of the flowering or fruiting. Young leaves of medicinal plants were gathered throughout the growing period to maximize the quality of active compounds. When the whole herb was required for medicine, the herb was collected at the beginning of the flowering stage. Fruits and seeds of medicinal plants were collected when mature. The bark was collected when trees and shrubs began to bud in spring and after leaves shed in autumn (Kaul, 1997; Kala, 2002). In the Himalayan region of Nepal, young leaves, if required, are harvested in the spring, flowers and mature leaves in the summer, and fruits, seeds and rhizomes are collected in the autumn. In the Tibetan Medicine System, the harvesting of medicinal plants is determined by the cultural and religious calendar. In late September or early October, when most of the alpine plants complete their life cycle, Amchi (medical practitioners of the Tibetan Medical System) collect plants to prepare medicine (Ghimire et al., 2004; Kala, 2005d). 22

Since the MAP forms a large group of species with variety of growth forms, responses to environment and life forms along with mode of their harvesting are also diverse. Similarly, after harvesting the recovery of species depends on various environmental and ecological factors. MAP tolerance to harvest varies with climatic conditions as the temperate herbs become highly vulnerable to harvest of individuals (Ticktin, 2004). Furthermore, rising demand with shrinking habitats may lead to the local extinction of many medicinal plant species. For instance, the current practice of gum collection from some MAPs, such as, Commiphora wightii and Canarium strictum is no more sustainable because of changes in traditional gum collection strategies and weakening of customary laws. Earlier, as soon as the natural fissures appear on the C. strictum tree, the local people in south India chip the resin protruding from the large tree (Varghese and Ticktin, 2008). Only few individuals collect resin regularly and fulfil the demand of rest of the villagers. Collection of resin from naturally formed fissures has proven advantageous over the artificially formed incision on the tree (Varghese and Ticktin, 2008). Studies conducted across various eco-regions have culminated to the point that indigenous methods of resource utilization are often more sustainable than most globally and commercially oriented practices, hence traditional ecological knowledge is a powerful tool for conservation and management of natural resources, including MAPs (Ghimire et al., 2004; Ticktin, 2004; Kala, 2005b). DISCUSSION There are some inherent problems with MAPs conservation. It is believed that MAPs collected from the wild have greater efficiency than those cultivated commercially as crops. Although there are many advantages of domesticating wild MAPs and conservation is one of them, the success rate of many species is low due to their specialized environmental requirements. Precariousness of market forces also creates a fear among MAPs growers. A plant, which has a powerful market today, may not have the same market tomorrow, for example. Further, the changing life style and socioeconomic values have superseded the traditional values. Though laws have been enacted to prevent over-harvesting but illegal collection is continued (Kala, 2002). Influential people even hire laborers from outside. These laborers are not trained and hence the unsystematic and unscientific harvesting of many high value MAPs has led to increasing rarity of such species. To understand the species rarity in view of their conservation needs, it is imperative to have the ecological information in terms of their population status, habitat preferences and distribution pattern. However, the meager availability of data, especially on the population density of MAPs in the wild has restricted their categorization to a few species on the basis of herbarium collection and by consulting a few experts (Kala, 2000). The problem in assessing MAPs is increased to the remote areas, and therefore the available data are not sufficient to determine the species rarity (Kala, 2005b). It is important to understand the population status of MAPs for setting priorities for their conservation. In addition to this, different use patterns of MAPs across the society determine the degree of threat to the concerned species. The Santalum album of the Mysore region in South India, Rauwolfia serpentina of the Neemach region in central India, and Aconitum heterophyllum of the Uttarkashi region in northern India are considered to be of the best quality available. Since the genetic diversity within species makes possible the commercial breeding of higher-yield and disease-resistant plants, and allows for adaptation to changing climatic conditions, identifying locality specific populations of MAPs may help for setting proper conservation measures. Globally, more than 52,000 species are known exclusively for their medicinal properties and within India about 6,500 species are reported as medicinal plants (Schippmann et al., 2002; Hamilton, 2004; Kala et al., 2006). Within this large group of medicinal plants, because several species are under various threats, it is important to prioritize the important species for conservation. A set of criteria may be identified for this purpose, which may include the mode of harvesting, population status in the wild, 23

endemism, use value (number of uses of a species), commercial value, rarity status, etc. Through applications of 4 major parameters such as rarity, endemism, mode of harvesting, and use value, a total of 17 important medicinal plants have been prioritized for immediate conservation in the Himalayan region of India (Kala et al., 2004). Such models may be designed and applied for prioritizing MAPs of different biogeographic zones for long term conservation and management. There are many threatened MAPs, which need special care and attention. Santalum album, for instance, grows in the Western Ghats and like many other religious plants it is used in worshipping Hindu gods since antiquity. Because of its high and increasing prices (within the past 5 years $ 1000-1500 for per kg essential oil) and despite the fact that the Government of India owns all sandalwood trees and there is strict control on their harvesting, many trees are illegally harvested and smuggled out of the country. This has led some countries to think and regard the sandalwood oil trade as ecologically harmful because it encourages the overharvesting of sandalwood trees. Large scale farming of useful and threatened MAPs is mostly recommended as possible solutions for their conservation in the wild. Based on this philosophy the Government of India has been promoting large scale cultivation of MAPs for the past couple of decades. More than 80 species of MAPs have been selected and brought under cultivation. However, the proper agro-techniques are available for only a small fraction of such species. So far more than 40,000 ha of land is claimed to have been brought under cultivation of MAPs, exclusively in the supervision of one of the departments of the Government of India, the National Medicinal Plants Board. Besides, an area of approximately 20,000 ha of land is brought under in situ conservation measures and >4,000 under development of herbal gardens. However, still it is a matter of scrutiny to prove or disprove the notion that present cultivation policy has benefited the conservation of MAPs in their natural habitats. An integrated management approach is strongly felt in order to address the local people’s concerns and to mitigate the conflicts while conserving the MAPs. The adaptive indigenous knowledge, practices and perceptions associated with surrounding complex environmental and ecological systems may cope with the uncertainty of the ecosystems and diminish the intensity of ongoing impacts. The long association and historical continuity of local people to their surrounding natural resources make them understand not only the ethnobotanical uses of species but also the complexity of locality specific ecological systems. The conservation practices for useful ethnobotanical species developed by these people are grounded in a series of rules of thumb, which involve an intimate relationship with the belief system. Although such knowledge may not be explained in a modern sophisticated scientific doctrine, it is vital and has been useful in conserving species from antiquity (Gadgil et al., 1993). Dovetailing both ethnobotanical and ecological tools used for their conservation is required for sustained availability of such useful natural resource. There are also opportunities to incorporate the conservation policies for MAPs within the framework of existing legal instruments such as, the Convention on Biological Diversity and the Convention on International Trade of Endangered Species of Wild Flora and Fauna. Since the Convention on Biological Diversity under Article 8 (j) has strongly recognized the importance of indigenous knowledge for conservation of biodiversity, the policy makers and academicians may need to synergize the values of ethnobotanical and ecological knowledge for conservation of useful species. In the present era of globalization, especially in the democratic countries, a need of participatory approach seems to be more suitable for viable conservation of MAPs. ACKNOWLEDGEMENTS The author thanks the Director, Indian Institute of Forest Management, India for help and support. Prof. Dea Baričevič, University of Ljubljana, Slovenia and Dr. Friedrich Pank of Germany are acknowledged for help during the course of writing the paper.

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