Keywords

Wild plant resources in agricultural systems; Native food culture; Community nutrition and health; Traditional farming practices; Local ecological knowledge

Introduction

Global food security now depends on a few widely cultivated species, the three crops, wheat, maize and rice providing over 50 percent of the world's daily requirement of proteins and calories [1] and 12 species contributing about 80 percent of total dietary intake. By contrast, wild foods provide a greater dietary diversity to those who rely on them. More than 7000 species have been reported to be used at some stage in human history, in past, based on ethnobotanical surveys of wild plants [2]. In India, 600 plant species are known to have food value [3]. Many agricultural communities have been reported to rely on wild plants and animals even today.

It has been reported that the agricultural and forager communities at 36 locations in 22 countries of Asia and Africa use an average of 90-100 wild species [4]. The access and availability of wild food resources is now declining due to habitat degradation, developmental activities, agricultural expansion, and other social and ecological drivers reducing wild food use. However, with increasing pressure on enhanced agricultural productivity, the importance of wild food use has been reported to be set to grow [4].

Wild plants in particular are reported to have diverse uses [5-7]. Wild plant foods have been an integral part of human diet since ancient times and nearly 75,000 species of plants believed to be edible [8-11]. About 200 plant species have been domesticated as food crops of which only about 30% are reported to contribute 95% of the world’s plant food intake [12,13]. However, despite the reliance of agricultural communities on conventional crop plants, the rural communities world over still consume wild plant foods [13-17], in its state of food insecurity in the world report, estimated that around one billion people use wild plants in their diet.

Wild vegetables play an important role in the diet of inhabitants of different parts of the world. Afolayan and Jimoh [18] reported that the nutrients available in wild vegetables of South Africa, Chenopodium album, Sonchus asper, Solanum nigrum and Urtica urens are comparable with or higher than those of commonly used vegetables such as spinach, lettuce and cabbage. In terms of antinutritional principles, all the vegetables had comparatively lower concentrations of phytate, alkaloids and saponins. Misra et al. [19] documented 21 wild harvested leafy vegetables from six villages of Nanda Devi Biosphere Reserve buffer zone in Uttarakhand state, India. Irrespective of social or economic status in the study villages, the farmer households had enough knowledge about availability and use of these wild leafy vegetables. The traditional knowledge, however, is eroding fast due to changing social values and non-participation of younger generation in collection and processing of such wild food resources. In an ethnobotanical investigation carried out in Kendrapara district, Odisha, India, Panda [20] reported that within the edible plant parts, leaves and fruits contributed maximum (about 75%), the remainders being edible tubers, flowers and seeds. The utilization of wild vegetables in the dietary intake of the households was emphasized.

In Uttarakhand hills, rural farming communities still gather and consume many edible wild plant resources [21]. Rural communities use these food plants to supplement their diets. Consumption of these plants is particularly vital when there is food shortage besides contributing to livelihood security and household economies of native communities. Their importance is exemplified by free and easy accessibility and nutritional richness especially vitamins and micronutrients. Therefore, they play a significant role in the livelihoods of rural communities in Uttarakhand hills.

Research on wild harvested foods in traditional agro-ecologies from forestry/agroforestry systems has so far received limited attention but it is a matter of great concern from various researchers now. Inventorying, in situ conservation and their promotion and commercialization are some important actions required for conservation and sustainable utilization of wild and neglected food plants. As most of the wild plant resources are used locally, their many values remain undocumented without being reflected in local, national or international markets. Systematic documentation of indigenous knowledge regarding the identity and use of wild harvested foods by rural communities is therefore a necessity as a growing disinterest among the younger generation in the community is often observed.

The proposed study titled “Indigenous land and food systems in Uttarakhand: A case study on traditional knowledge and use of wild foods in agricultural systems” therefore sought to:

Inventorying wild edible food plants from traditional farming areas of Uttarakhand hills with particular emphasis on indigenous community knowledge regarding their identity and use, an integral component of subsistence hill farming.

Determining the food preparations, marketability and conservation of wild harvested foods.

Determining impact of the loss of traditional knowledge and lack of use of wild food resources on community health and nutrition.

Prioritizing wild food plants for research and marketing interventions in specific agro-ecologies of Uttarakhand hills.

Farmers’ work in the food system is based on their knowledge and skills. Documenting complex farmers’ knowledge for food; documenting experiential knowledge based on community culture; bio-diversity knowledge based on nature; gender division of labour, etc. with major emphasis on wild harvested food resources will also be addressed in the present case study using participatory approaches.

Description about the Study Area

Of the total geographical area of Uttarakhand state about 13.5% (766730 ha) is the net sown cropped area. About 86% geographical area of Uttarakhand is hills but the crop lands are mainly in plains, popularly known as the Terai and Bhabar region, where modern farming is practiced under assured irrigation. On the other hand, in hills, traditional mix cropping practices are normally practiced, and farming is mainly rainfed. In Uttarakhand more than 75 percent of the population depend on agriculture for their livelihood. The three important representative agroecologies/ farming situations in Uttarakhand hills: i) small-scale crop-livestock mixed-farming systems representing about 70% of the net sown rainfed farming area; ii) high elevation mountainous valleys adjoining Tibet mainly inhabited by nomadic pastoralists, the Bhotia or Shoka tribes and comprising about 10% of the net sown area, and iii) a few interspersed river valleys with improved agriculture under assured irrigation, comprising about 10% of the cropped area of the Uttarakhand hills.

In an exploratory survey more, household production and dietary diversity was revealed for traditional rainfed small-scale crop-livestock mixed-farming systems followed by mountainous valleys with nomadic pastoralists, and least in river valleys with improved agriculture. In hill agriculture, only farmer-led traditional innovations are predominantly practiced except in river valleys where use of improved varieties, inorganic fertilizers, pesticides, is now commonly seen. However, in the mixed croplivestock farming system of the hills, a dynamic relationship among CPRs, native crops and livestock, still exist to a greater extent. The livestock predominantly contributes to the household cash income whereas the surplus crop produce, if any, is sold locally and contributes very little to the household agriculture economy. The nomadic pastoralists of high mountainous valleys all have some arable land beside foraging and trading of medicinal herbs. Sheep and goat are the herded livestock. Tending of livestock and foraging of medicinal herb for export purposes is common. Livestock grazing is practiced throughout the mountain valleys, although at rates significantly lower since the Indo-China conflict of 1962. Largely because the loss of trade with Tibet, the demand for livestock and agriculture products has dropped considerably.

A nutrition transition is clearly evident in farming situations particularly of river valleys with the emergence of cash crop economies and impact of globalization in recent years. Even in traditional farming areas nutrition transition in evident in a limited way. With the nutrition transition resulting from increasing socio-economic change, the problems of underweight and overweight is frequently co-existing. Besides, undernutrition, the socio-economic disparities and increased access to energydense foods are also creating an "obesogenic" environment in some sections, more particularly in river valley areas.

The niche target sites (20 nos.) for documenting information on wild harvested plant resources in different agroecologies are presented in

Research Methodology

Data on wild harvested plant food resources were documented from all 20 representative niche sites (Figure 1 and Table 1) of three main farming agro-ecologies of Uttarakhand hills during January to May 2017. Data were mainly documented for local ecological knowledge/indigenous knowledge (LEK/IK) on identity and use of wild plant food resources using semi-structured questionnaires. For interviewing the farmer households, a checklist of open ended questions was used. Free listing technique was used for gathering data on indigenous knowledge pertaining to wild edible plants. Each respondent was asked to mention any plant that comes to their mind until they could not mention any more species. It was presumed that people in any community do remember plants which are important to them. Respondents were also requested for field guided walks to all nearby areas in the community including nearby forestry areas to identify/ collect the plants listed during the interview. One Focus Group Discussion (FGD) meeting each was held in all agrobiodiversity rich niche target sites to authenticate the data in questionnaires and capture additional responses on value of wild plant foods for household food and nutrition, contribution to household economy, drivers of change in availability and use of wild plant food resources, unsustainable harvesting and changing dynamics, loss of LEK, socio-economic change, etc. Potential of a few prioritized wild plant food resources for marketing interventions was also explored.

Figure 1: Map of the study area.

Table 1 Niche sites in different agro-ecologies of Uttarakhand hills for documenting wild harvested food resources.

The participatory interviews were done separately for men and women farmers of different age groups for LEK on wild harvested foods. Children (<15 years) were also interviewed for LEK. Average 10-15 farmer households were interviewed per niche site.

The nutritional value of a few wild plant food resources was also compiled from secondary sources.

Results

Documenting wild plant food resources of Uttarakhand hills

A complete list of wild plant food resources from different representative niche sites of three distinct agro-ecologies was documented. A total of 335 plant species was recorded in different plant families of Angiosperms, Gymnosperms and Pteridophytes. A total of 97 families of dicotyledons and 12 families of monocotyledons, in Angiosperms; three families of Gymnosperms and one family of Pteridophytes (Ferns) were represented (Table 2). Rosaceae (25), Polygonaceae (15), Fabaceae (12), Asteraceae (11), Lamiaceae (10), Liliaceae (10), Urticaceae (10), Amaryllidaceae (Alliaceae 8), Amaranthaceae (8), Caesalpinaceae (7), Rutaceae (7), etc. were the plant families with greater species representation among angiosperms. Important plant species in different agroecologies and farming situations are listed in Table 3.

Table 2 Plant species used as wild harvested foods in Uttarakhand hills.

Table 3: A few important wild plant species commonly used by farming communities of Uttarakhand hills.

Domestication programmes are also being initiated by Uttarakhand state to bring many wild species, mainly the local herbs in farming systems. Examples of important plant species for domestication interventions include, Allium stracheyi, A. humile, A. wallichi, Asendra butyracea, Malus baccata var. himalaica, Sorbus lanata, S. cuspidata, Fragaria nubicola, Rubus macilentus, R. ellipticus/R. biflorus, R. nutans, Hippophae rhamnoides spp. salicifolia, Rosa sericea/R. macrophylla, Cleome viscosa and a few others (Table 4). These species can help provide livelihood support, health and nutritional benefits to local communities.

Table 5 Direct use values of wild plant foods for household consumption or income from sale in niche target areas of three representative farming situations.

The economic and nutritional value of wild foods

Table 5 summarizes the findings from economic valuations of direct use values for wild foods in selected farming agro-ecologies of Uttarakhand hills. The exploratory surveys for some important species reveal that wild plants can provide INR 5000-500000 per households in specific agro-ecologies/niche areas of Uttarakhand hills.

It was found that poorer households are normally involved in wild harvesting and marketing of wild plant food resources. Table 6 presents information on trends in market sale of some wild harvested foods, mainly as vegetables and fruits in the Nainital district of Uttarakhand. A substantial income has been reported by farmer households, those engaged in wild harvesting and their trade in local markets.

Table 6 Sale of a few important wild harvested plant food resources in local markets of district Nainital.

Nutritional profile of some wild food plant resources compiled from secondary sources is presented in Table 7 [22]. It is clear from Table 7 that many of the wild harvested food resources are often considered superior in energy and micronutrient content compared with those from many cultivated species.

Table 7 Nutritive composition of some wild edible plant resources.

Leading factors for change in wild food availability and use

The leading factors affecting wild food availability and use are listed in Table 8. Table 8 reveals that resilience to climate change is more by wild species compared to crop species under cultivation and cultivated species of exotic origin that have been naturalized in local farming situations. Land use change and degradation including poor management of CPRs; unsustainable harvesting and changing dynamics; loss of LEK; socio-economic change and the market expansion due to globalization, etc., have been other drivers impacting availability and use of wild plant food resources.

Table 8 Drivers of change in wild food availability and use.

Discussion

Wild foods have long been used by farmers, as ‘hidden harvests’, and have supplemented their dietary diversity and household income [2,23,24]. In traditional farming systems of Uttarakhand hills, the agroforestry and forestry based wild plant resources supplement household food choices and ensures dietary diversity and better nutrition. Wild gathered tubers, fruits, seeds, twigs, leaves and flowers of several plants still form minor but important food components of the rural communities (Table 3). However, availability and access to these foods is declining as natural habitats are under constant pressure from developmental activities, poor management and conservation-exclusions. The climate change and recurrent droughts are adversely affecting availability of the wild food resources. Further, the ‘nutrition transition’ and inflow of purchased foods are also negatively impacting the value of wild harvested foods.

It has been observed that most wild harvested plant products are consumed directly within the farmer households, hence it is often difficult to capture the quantity and diversity of the harvest at local or national level [24]. Tables 5 and 6 confirms that some wild edible plant foods contribute substantially to the household dietary diversity and economy as well, whereas they have the potential to enhance household incomes once fully tapped (Table 6).

It may be emphasized that ‘malnutrition is a major health burden in developing countries and use of wild plant foods can be enlisted as policy support to secure wild food use and preserve habitats for wild edible species’ [4]. Comprehensive food composition is therefore critical especially for communities most vulnerable to malnutrition [18,19]. We, however, have limited understanding of micro- and macro-nutritional properties of wild foods as compared to cultivated species.

Several wild edible plants are sources of important micronutrients, Fe, Ca, P, Na, K, Zn, etc. Table 7 lists that many wild food resources of Uttarakhand hills are rich in micronutrients [22]. Many wild backyard plants and plants in agroforestry systems (CPRs) have edible parts that are commonly consumed and are critical suppliers of vitamins A, B2, C, antioxidants, especially during seasonal lean periods. Many are important as famine foods, ensuring year-round nutritional security in the face of possible food shortages.

The food and medicinal uses of wild plant food resources as fruits and vegetables is known to lower risk of several oxidative stresses, including cardiovascular diseases, cancer and stroke and such health benefits are mainly ascribed to phytochemicals such as polyphenols, carotenoids and vitamins. Of these phytochemicals, polyphenols are largely recognized as antiinflammatory, antiviral, antimicrobial and antioxidant agents.

The wild fruits are gaining increased attention now as potential food supplement or cheaper alternative of commercial fruits across the world. Evidences of the health benefits of wild edible fruits, in addition to established role in nutrition are available. In general, enough information is available on the antioxidant potential of fruits of different species. Some examples include: Actinidia eriantha, A. deliciosa, Ficus carica, F. microcarpa, F. racemosa, Juglans regia, Kadsura coccinea, Myrciaria dubia, Phyllanthus emblica, Punica granatum, Randia echinocarpa, Ziziphus mauritiana and so forth. Beside the fruits, antioxidant properties are also known for other plant parts.

There is no comprehensive estimate of the economic value of wild foods [4]. Quantitative analyses face methodological difficulties. Further, the trade of wild foods is often informal or occurs at local markets and is, therefore, missed by conventional accounting mechanisms [25].

A few prioritized species of potential importance in Uttarakhand hills contributing to livelihood and nutritional security of local communities require science and marketing related policy interventions. Myrica esculenta, Diplazium esculentum (a vegetable fern), Phyllanthus emblica, Oreganum vulgare, Cleome viscosa, etc. in mid-hill areas under rainfed farming landscapes and Allium spp., Carum carvi, Angelica glauca, etc. from mountainous meadows can be discussed here in greater details (Table 9).

Table 9 Discussions on prioritized plant food resources with proven marketing potential in Uttarakhand hills.

A number of important drivers of change for wild food a vailability and use have been reported [4]. Food insecurity, for instance, is a particular problem among local communities with croplivestock small-scale mix farming situations followed by nomadic pastoralists and least in households of river valleys in Uttarakhand hills. Cultural identity and agrobiodiversity are strongly associated, culture and ecosystems are known to co-evolve. Thus, a biophysical driver (e.g. climate change) could have knockon effects on a cultural parameter (e.g. local knowledge), and the effect of the two combined could lead to either an increase or decrease in wild food use [4].

A comparison of farming communities of three distinct agroecologies of Uttarakhand hills revealed insufficient evidence to predict the impacts that climate change on both human foraging and the interlinked processes of LEK transmission, cultural continuity and land-based subsistence livelihood. Forecasting the precise impacts of the changing climate on the availability of wild foods is difficult but the supposedly inherent resilience of wild species to rapid climate change as compared to cultivated or exotic species means that they could play an increasingly important role during periods of low agricultural productivity associated with climate events [4].

Decline in management of CPRs including expansion of intensive agriculture and urbanization have significant implications for the availability of wild foods, the commercialization of agriculture— an important driver of land use change-potentially implies decreased reliance on wild foods [26]. Agricultural and land use policy, infrastructure development and widened access to markets all drive land use change and are implicated in declines of wild species [27-29].

Most of the wild food species used by local communities come from well managed CPRs and agroforestry systems rather than mature forests. The 20 niche habitats surveyed in the present exploratory study, poor management of CPRs and deforestation had led to a decline in wild food species. Lack of sustainable intensification calls for a biodiversity-focused strategy in food, public health and poverty-alleviation policies [4].

The Indian Himalayas including the Uttarakhand hills is one of the global hot-spots of biodiversity with areas of greater malnutrition and hunger, also placing pressure on biodiversity for food provision. In certain niche habitats, unsustainable harvests have led to declines in wild food species. Unsustainable harvesting is a concern in the case of wild food resources of high elevation areas in Uttarakhand hills, more particularly “Jambu or Faran” (Allium stracheyi and A. wallichii) and “Gandhrain” (Angelica glauca), two important wild harvested commodities from alpine meadows/bugyals of Uttarakhand hills. The treasure nature has given us for medical purposes, but that does not justify the use of uneven means for any selfish motives.

Loss of LEK has been observed in Uttarakhand hills. A strong inverse correlation has been reported by Pilgrim et al. [30] between ecological knowledge and income levels. Understanding ecological knowledge loss is important to understanding the declining capacities of communities undergoing economic development to manage their natural resources and the future of ecosystem diversity in the light of current patterns of economic growth [30]. It was interesting to note that in low income communities of small-holder crop livestock farming systems and that of resource-dependent low-income communities of higher Himalayan mountainous regions, LEK was found to be higher and rate of knowledge acquisition rapid from a young age. This suggests that as communities become wealthier, knowledge becomes concentrated in fewer people with a sustained personal interest.

The distribution of LEK between individuals in a community has been reported to be differentiated by gender, age or social role [4]. Data from the 20 niche sites, women above 40 years of age were able to describe the uses of about 70 per cent of all edible species, while young men could only describe 15-20 per cent. Similar findings have been reported from a study from Nepal [5]. Men and women might also hold specialized LEK. LEK is also differentiated by age [5].

A significant decline was recorded in LEK where communities rely increasingly on market-bought foods and move away from land-based livelihoods [30]. In certain farming landscapes, it was observed that the grown-ups usually succumb to the culture of the society where consumption of wild fruits is regarded as an inferior act. Further, the LEK decline (in terms of species names and uses) is associated with increasing disconnection and livelihood independence from agricultural and wild systems as a consequence of modern economic growth.

LEK is likely to be substituted by modern environmental knowledge about global warming, energy saving techniques and organic foods for example. This global knowledge is, of course, essential but should not replace that of our local ecosystems [4].

The nutrition transition associated with modernization of diets poses challenges to public health in hill communities. The replacement of wild foods by market-bought products is linked to reduced dietary diversity, rising rates of chronic lifestyle-related conditions such as obesity and type II diabetes, poor intake of micronutrients and malnutrition. Traditional species become undervalued and underused as exotic ones become available. Yet, the importance of wild foods to nutritional security means that they are not necessarily replaced by market-bought foods providing the same amount of calories. When more people depend solely on market-bought (cultivated foods), consuming wild foods will be marginalized [4].

As Uttarakhand hills have a strong food culture, traditional food systems can persist, and wild foods are still prevalent enough to be considered an important part of local diets particularly in crop-livestock mix farming systems and pastoralist communities of higher Himalayan ranges.

The nutrition transition is driven by a changing climate as well as large-scale cultural changes and is expected to produce significant negative effects to physical and mental health at community level. Niche habitats where children use wild edible fruits and vegetables, level of malnutrition was low and the benefits of consuming traditional wild foods were clearly evident. Though wild foods have played a critical role several traditional farming area across the globe including circumpolar communities, public health policy generally operate within a model of food security that discounts the traditional food practices of native communities [4,31,32].

Conclusion

Wild plant food resources form a significant portion of the dietary diversity of the farmer households of Uttarakhand hills. However, the contribution of wild harvested foods to total food and nutritional security is under-researched. Constant efforts to increase agricultural production and enhance economic development have threatened the continued contribution of wild species to food and nutritional security. Further, the sustainable harvesting of wild economic species requires a strong policy support by ensuring its continued availability for livelihood and nutritional security of local communities.

Use of wild food resources is part of culture and traditions of hill communities of Uttarakhand and is part of their living link with the land. Decline in traditional ways of life is interlinked with decreased wild food use. Wild food species, therefore, provide more than just food and income to hill communities. Polices on conservation, food-security and agriculture, therefore, need to be integrated to recognize and preserve the importance of wild foods.

Traditional food revitalization projects aimed at increasing the consumption of wild foods, in order to provide health and cultural benefits to traditional communities otherwise subject to the nutrition transition is considered a necessity. It is a well-recognized fact now that wild species and intra-species biodiversity have key roles in global nutrition security. The wild foods still provide substantial health and economic benefits to those who depend on them globally. The efforts to conserve biodiversity and preserve traditional food systems and farming practices, therefore, need to be combined and enhanced.

Acknowledgement

The authors thank the Director, ICAR-NBPGR, New Delhi for providing facilities for the exploratory surveys in parts of Uttarakhand hills. The farmer households from different niche habitats of Uttarakhand state deserve our thanks for interacting with the research team and sharing the valuable information they possess on traditional agricultural innovations, native resources and food systems.

Funding

Financial support received from the Jawaharlal Nehru University, New Delhi for a case study titled “Indigenous land and food systems in Uttarakhand: A case study on traditional knowledge and use of wild foods in agricultural systems” under DST Network Programme on Traditional Knowledge Systems in the Indian Himalayan region is duly acknowledged.

Disclosure statement

No potential conflict of interest was reported by the authors.

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