Ethnobiology Research Paper

One of the concerns of ethnobiologists and related researchers is to document and assess the value of ethnobiological information, especially in regard to rapidly depleting biodiversity and other forms of ecosystem degradation. Unlike modern human societies whose impact upon ecosystems may be seen as exogenous transformations, traditional societies tend to influence the functioning of ecosystem from within (Ramakrishnan et al. 1998) in order to derive a variety of benefits. These benefits are of three kinds: (a) economic—traditional crop varieties and lesser known plants and animals of food value, medicinal plants, and so forth harvested from the wild (Ramakrishnan 1992); (b) ecological social—manipulation of biodiversity for coping with uncertainties in the environment and global change, for controlling soil water regimes and hydrology, soil fertility management through soil biological processes, and for efficient organic residue management; and (c) ethical—cultural, spiritual, and religious belief systems centered around the concept of the sacred species, sacred groves, and the sacred landscapes.

2. The Context

Ethnobiology started off as an appendage to classical taxonomy and systematic biology, essentially listing species collected from the wild and used by traditional societies. Whilst there is much accumulated literature of a descriptive nature on the food and medicinal species used by traditional societies from different parts of the world, which in itself is important (National Academy of Sciences 1975, Jain 1991, Berlin 1992, Hladik et al. 1993), it is only recently that ethnobiology has begun to look at the dynamics of the relationships existing between individual species and populations, and between ecosystems and landscapes.

A pioneer of ethnobiology, Conklin (1954) distinguished two distinct shifting agricultural (swidden) systems among the Hanunoo forest farmers in the Philippines: (a) the ‘partial’ performed by migrants from outside and using swidden as a simple means of producing a crop and (b) the ‘integral’ reflecting the traditional, year-round, community-wide, largely selfcontained and ritually sanctioned way of life. Subsequently, a plethora ethnobiological research has followed, exemplified by the work of Kunstadter and Chapman (1978) which classifies swidden systems in Thailand on the basis of the use of resources and the relationships between cultivation and fallow periods in these agroecosystem types. Ramakrishnan (1992) has further elaborated this typology for north-east India, taking into consideration ecological, socioeconomic, and cultural considerations. ‘Traditional Ecological Knowledge’ (TEK) emerges from such work and constitutes a rapidly evolving area of research (Johannes 1989), with serious implications for our understanding of the human dimensions of ecology. That TEK is often embedded in local belief systems blurs the heretofore boundaries between ethnobiology and ethnology (Ramakrishnan et al. 1998).

There is an increasing realization that traditionally valued species could play a more important resource role for society at large, including food and medicinal resources (National Academy of Sciences 1975). More recently, however, interest in TEK has moved in the direction of understanding the interconnections that exist between ecological and social processes, determining the functional attributes of ecosystems landscapes (Ramakrishnan 1992), and exposing the long-term interactions between nature and society that give rise to ecosystems that might otherwise be seen as ‘natural’ (Alcorn 1984). The way in which traditional societies perceive and manipulate bio- diversity in the landscape, both in space and time, to ensure ecosystem stability and resilience, and have evolved ecologically sound biotechnologies of land management, such as those geared for soil fertility and soil water enhancement, to cite two examples, are now deemed important for environment and development and, increasingly, for global change science (Ramakrishnan et al. 1996). At the rate at which global change is occurring, a major proportion of all species on earth will be lost over the next century, and yet it is those species that we need to build a secure future (Raven 1998). TEK offers improved understanding of ecosystem maintenance and, hence, species preservation as well as holistic and cost-effective approaches to sustainable development.

3. Economic Benefits

There have been various attempts to evaluate the economic value of tropical forest biodiversity used by traditional societies, apart from the fact that these species provide basic subsistence. Such evaluations are partial, largely concerned only with the direct uses, and rely upon various assumptions about and mechanisms for attributing market values. Examples include an annual value of US$16–22 per ha for the forests near Iquitos, Peru, in Amazonia (Padoch and de Jong 1989), and US$117–244 per ha for non-timber forest products used by forest dwellers from different parts of India (Chopra 1993).

3.1 Medicinal Plants And Alternate Medical Systems

The ethnobiology of medicinal plants from the tropics has been rediscovered, complete with an understanding of how traditional uses reflect alternative medical systems. The traditional system of medicine in India, Ayurveda, provides many medicines from the Neem tree, Azadirachta indica. The recent commercial patenting of the active principle Margosan-O derived from this tree, which has been extracted successfully, chemically stabilized, and patented by Western industry for its pesticidal properties, is an elegant example of commercial exploitation of traditional knowledge. The term exploitation is appropriate, given that this species has been part of the Indian traditional systems of medicine since antiquity, and yet the economic rewards of the patent do not return to the people on whose knowledge the patent is partially based.

Alternate medical systems currently form the basis of primary healthcare for a very large number of the world’s population. The role of these indigenous practices in addressing the healthcare needs of developing countries, integration of these alternate systems into the national planning process, and investments for capacity building to preserve and perpetuate this traditional knowledge and for renewed research to build upon this knowledge base, increasingly is recognized (Bodeker 1994). In spite of a variety of myths that marginalized traditional healthcare in the past (Fig. 1), some developing countries, such as India and others from Asia, have taken steps to strengthen research on these remedies and to integrate the holistic practices into the national healthcare. These events challenge the belief that Western medicine is the only effective way of dealing with health problems and seek to provide complementary therapy.

TEK health systems have served some 2,800 culturally distinct communities living in India composed of over 50 million ‘tribals’ belong to over 600 ethnic communities (Dube 1998). About 76 species of animals—16 invertebrates and about 60 vertebrates— are known to be part of the tribal medicine in India alone. Over 9,500 wild plants are recognized to be of ethnobotanical value of which over 7,500 as medicines, 3,900 as edibles, 500 for fibre, 400 as fodder, 300 as pesticides; many of them have the potential for commercial exploitation (Ministry of Environment & Forests 1994). The Ayurveda system, noted above, can be traced to Vedic (Hindu religious texts of antiquity) times (circa 1500 BC). With vegetable products dominating this ancient medical system, diet, and drugs derived from plants were considered to be part of a holistic approach to treatment of diseases. Reserpine yielding Rauwolfia serpentina for hypertension and a gum that is hyoplipidemic drug yielding, Commiphora wightii, are just two examples of the untapped wealth of resources available in this system. Apart from this, there are a variety of traditional medical practices, including the Unani system largely restricted to the northern part of India and the Siddha system in the southern region. With such a rich tradition in India alone and equally diverse systems elsewhere in the tropical world, the opportunities to develop refined drugs to feed the global market are vast. These cheap herbal remedies are part of a thriving alternate system of medicine, with minimal side effects in clinical experience (Valiathan 1998).

3.2 Lesser Known Plants Of Food Value

Humans have used a few thousand plant species and a large number of animals as a source of food collected from the wild. Of these, only a small fraction has been domesticated, and still fewer numbers are used extensively. Today, about 20 plant species largely sustain the entire world population with food. Alarms have been raised, however, that this reliance may be imprudent and concern mounts to consider an increase in the use of lesser known plants to meet food demands of a growing world population, especially those with less access to the dominant crops, to cover the possible risk involved in our dependence on those species, and to explore pathways for agriculture less dependent on high energy input, modern agriculture alone. Many of the lesser crop species are cultivated by traditional societies as part of multispecies complex agroecosystems, others are collected from the wild (Swift et al. 1996). These considerations prompted a panel of experts of the US National Academy of Sciences (1975) to evaluate a range of under-exploited tropical plants of promising economic value, and select list of a few dozen species that, in their opinion, hold promise for development. Similarly, another set of promising leguminous species were identified for their value as food, fodder, timber, gum, green manure, and soil reclamation (National Academy of Sciences 1979).

3.3 Traditional Tropical Phytopractices

Moving from individual to collective species, Halle (1996) identifies a variety of manipulation techniques and practices applied to individual or groups of plants in order to improve the quality and quantity of products obtained from them (Fig. 2). He concludes that these traditional technologies from diverse geographical regions share some common features based on an intimate knowledge of plant growth that offer possibilities for transfer to other systems of plant management.

4. Ecological Social Implications

4.1 Interconnections Between Ecological And Social Processes

Historically, scientific research on biodiversity in ecosystem functioning omit humans in the definition of the ecosystem boundary, although the synergism between human activity, such as burning, and the resulting landscape have long been known. Traditional societies, intimately linked to the environment for their livelihoods, afford the opportunity to examine their part in the functioning of the ecosystem, especially in the tropics. In such contexts, the role of biodiversity in ecosystem functioning portends to change substantially as the social, economic, and cultural dimensions determining ecosystem properties are revealed. Such a shift in understanding the interconnections between ecological and social processes has implications for sustainable management of natural resources in developing countries in which local communities have a participatory role.

In this new approach, the village is seen as an ecosystem, with all its ramifications for agriculture, animal husbandry, and the domestic sector embedded with the forest and forest-related activities, such as hunting and gathering of food, fodder, fuel wood and medicinal plants collection, and forest-linked traditional farming practices, such as shifting agriculture (Ramakrishnan 1992, Swift et al. 1996). This approach integrates humans within the ecosystem. It implies that much ecosystem structure and function must be understood as an integrative process and that conserving biodiversity is crucial for the immediate survival of people and ecosystems.

4.1.1 Traditional Agroecosystems. Traditional societies maintain a variety of complex, multispecies agroecosystems, operated under varied levels of production intensity. These range from casually managed shifting agricultural systems through an array of rotational fallows, agroforestry systems, compound farms, traditional cash cropping systems, and crop rotation systems at the middle intensity levels, to modern high input agriculture. The ecological complexity of these agroecosystems are due to biodiversity (subspecific and species level—crop and associated biodiversity) both in space and time.

4.1.2 The Concept Of Home Garden. Of all the traditional agroforestry systems, the ‘home garden’ of the tropics, variously called kitchen, house, or forest garden, deserves special attention. They display much variation in their structural and functional attributes, depending on the ecological and social settings in which they occur. Imitating a natural forest with a highly stratified and compacted set of economically important trees, shrubs, and herbs in small plots of 0.5 to 2 ha, these gardens can have over a hundred species (Millat-e-Mustafa 1998). The household is able to obtain many of its requirements from this system year round, such as food products, firewood, spices, ornamentals, and medicinal plants. Detailed economic and energy output input analysis done on the north-east Indian systems (Ramakrishnan 1992) suggest that, generally speaking, these systems are highly efficient.

Contrary to suggestions that home gardens are confined only to more fertile soils, studies in Cherrapunji in north-east India indicate that they can also be a TEK response to declining soil fertility and site degradation from shifting agriculture (Ramakrishnan 1992, Millat-e-Mustafa 1998). In this case, more fertile conditions are humanly induced. Indeed, TEK-based changes in garden diversity, structure, and management have been reported from the upland central region of Mexico as a response to industrialization and population increase (Gliessman 1990). Such adaptations are a response to labor constraints, available off-farm employment opportunities, and insurance against possible loss of outside income.

Much more needs to be known about the organization and functioning of these unique humanmanaged ecosystems. A redeveloped system built upon TEK is critical to meet with sustainable livelihood concerns and provide cash income to traditional societies in the biodiversity-rich regions of the world, especially in the context of global environmental change.

4.1.3 Agroecosystem Biodiversity Manipulations. It is not only the mere presence of biodiversity and the functional role it has for traditional societies that is significant, but the manner in which these societies manipulate this biodiversity for ecosystem functional attributes and landscape integrity. In the shifting agriculture of the hills of north-eastern India, for example, the number of species in a mixed cropping system declines drastically with shortening of the agricultural cycle (Ramakrishnan 1992). The farmer also shifts emphasis from cereals under a long 30-year agriculture cycle, to tuber and vegetable crops under a shorter 5-year cycle, which are more nutrientuse efficient species. Even on the same slope, such crops are emphasized on the top of the slope and the less efficient ones are largely placed towards the base, reinforcing the diversity of species while improving production and risk aversion. Through mixed cropping involving a large number of species in space and time, and traditional weed management strategies, shifting agricultural farmers in north-east India, as elsewhere, ensure effective checks on nutrient loss during the cropping phase. The traditional weed management practice, where about 20 percent of the weed biomass is left undisturbed in the plot by the shifting agriculture farmer is also a practice common to the Mayan agriculture in Mexico, with implications for agroecosystem sustainability (Altieri and Liebman 1988).

Traditional societies also ensure the integrity of the systems at the level of the landscape. The Apatani tribe in north-east India have evolved elaborate wet rice cultivation systems that are adapted to gradients in soil fertility and water availability, linked with traditional management options possible within the landscape (Ramakrishnan 1992). Widening plots by digging adjacent higher ground down to an irrigable level seems to be successful responses to population increase and new market opportunities, as also demonstrated for Tara’n Dayaks of West Kalimantan in Indonesia (Brookfield and Padoch 1994).

The lessons learnt from such manipulations of biodiversity done both in space and time as adaptation to a variety of environmental changes involving population pressure, land degradation, biological invasion, and climatic uncertainties, are important for biodiversity management in resource-rich regions of the tropics (Ramakrishnan et al. 1996). These are being used to design strategies for agroecosystem redevelopment (Swift et al. 1996).

4.1.4 Pathways For Agroecosystem Redevelopment. TEK is embedded in the complex, multispecies agroecosystems maintained by their various custodians and offers a basis for more environmentally sustainable systems of resource production. The objective of TEK-based redevelopment efforts is to maximize production focused on in situ conservation of agro-biodiversity (Swift et al. 1996) and on strengthening internal processes for relative stability and resilience within the system (Altieri and Liebman 1988, Gliessman 1990, Ramakrishnan 1992, Woomer and Swift 1994). To achieve these goals, TEK focuses on cropping patterns based with such attributes, among others, as (a) optimization of production along a nutrient gradient where it occurs, (b) synchrony in nutrient release from the soil and uptake by the crop, (c) efficient recycling of biomass residues, and (d) weed management rather than weed control.

This approach to developing agroecosystems stands in contrast to the ‘green revolution pathway’ based on high intensity management predicated on external energy subsidies. To reach it often requires an ‘incremental pathway’ (Swift et al. 1996) which builds upon traditional systems in a step by step manner sensitive to ecological, social, and cultural constraints under which traditional societies function. This pathway builds towards a ‘contour’ one in which the full range of agroecosystem principles are employed to reach ecologically attuned but high levels of production.

4.1.5 Manipulating Natural Crop Biodiversity Through Keystone Species. The role of socially selected, ecological keystone species in conserving and enhancing biodiversity and manipulating functions in forest ecosystems has not been explored adequately. Keystone species provide critical ecosystem functions that help to preserve biodiversity. Often they are also socially or culturally valued as well. Therefore, they can be used not only to manage pristine ecosystems (Ramakrishnan 1992), but also to build biodiversity in degraded natural and human-managed ecosystems through appropriate rehabilitation strategies (Wali 1992, Lamb and Tomlinson 1994) that ensure people’s participation (Ramakrishnan et al. 1994). For example, in areas of north-east India where the shifting agricultural cycle is less than 5 years and the landscape is highly degraded, a legume of lesser known food value, Flemingia estita, is socially valued and used to support a 1–2 year fallow and even nonfallow system of cultivation. By fixing 250 kg of nitrogen per hectare per year, this keystone species ensures sustainability of these low-input agroecosystems, under conditions of extreme pressure on the land and low soil fertility (Ramakrishnan 1992). The adjacent successional forests are also enhanced by a socially selected keystone species. Nepalese alder (Alnus nepalensis), a nitrogen-fixing species, and many bamboo species (Dendrocalamus hamiltoni, Bambusa tulda, and B. khasiana) with ability to conserve nitrogen, phosphorus, and potassium play a key role.

The interphase between ecological and social processes, exemplified in socially selected keystone species, is critical for biodiversity management in the context of rapid change, but has only just started to receive research attention. Such keystone species may also be found within the sacred groves of traditional societies, as in the case of Englehardtia spicata, Echinocarpus dasycarpus, Sysygium cuminii, and Drimycarpus racemosus which conserve high levels of nitrogen, phosphorus, and potassium in otherwise highly infertile soils in north-east India. They are also found at the landscape level within indigenous ‘forest reserves’ set aside within the forest-agriculture landscape as found among the Tara’n Dayaks of West Kalimantan, Indonesia (Padoch 1993) and elsewhere (Alcorn 1984, Ramakrishnan et al. 1994). The species within these reserves are protected by strictly enforced, community rules of use, with implications for sustainability.

5. Ethical Considerations. Conserving The Sacred

In some cases, refugia in a given region are given the status of ‘sacred groves,’ complete with cultural beliefs, institutions, and practices that create ‘social fencing’ for relict ecosystems. Often these groves occur within derelict landscape, otherwise heavily affected by humans. To this concept can be added those of the ‘sacred species’ and ‘sacred landscape.’ The former are keystone or resource critical species as described above (e.g., sacred Basil, Ocimum sanctum, and Neem, Azadirachta indica). Sacred landscapes scale up from species and groves to large areas intermeshed natural and human-made ecosystems. The Ganga watershed of the Central Himalayan Garhwal region in India, for example, consists of a variety of landscapes sacred to Buddhists (Ramakrishnan et al. 1998), while sacred mountains exist elsewhere, such as the holy hills of the Dai of Xishuangbann in Yunnan province in China (Messerli and Ives 1997). Such landscapes and related uses are ancient in time and worldwide in distribution (Monasterio 1994).

The state-of-art ecological knowledge on conserving this sacred cultural heritage is now synthesized (Ramakrishnan et al. 1998) with a view towards biodiversity conservation and seeking new paradigms for sustainable management of natural resources. Ethnobiology has, thus, evolved through TEK towards a holistic view in which ecology, economics, and ethics combine. A major aim is to recast the circular connections among them, now broken (Bormann and Kellert 1991), in order to provide alternative understanding and means of addressing questions of environment and development.

6. Conclusions

Ethnobiology has moved from an important descriptive stage of study to an even more important understanding of the linkages between ecological and social processes as they affect biodiversity and ecosystem functioning. This understanding, in turn, is being used to address biodiversity conservation and sustainable land-use management. Ethnobiology also lends itself to system-level assessments, linking its process studies to traditional agroecological management strategies, such as water harvesting systems, which can be used to produce for human consumption while triggering ecological rehabilitation. It is heartening to witness the growing recognition of the historic and existing interaction of various cultures with their surrounding ecosystems and landscapes and the extent to which these interactions have shaped them. Thus, ethnobiology increasingly promotes synergism between science and world views arguing against the segregation of the biosphere into the ‘natural’ and the ‘people,’ and for holistic concepts, such as the ‘biocultural region’ (e.g., Walton and Bridgewater 1996). Based on this movement, ethnobiology is becoming increasingly relevant in the area of sustainable management of natural resources, with concerns for livelihood and development of traditional societies based on a value system that they understand, appreciate, and therefore engage.

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