Ecological problems due to shifting cultivation

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The current practice of shifting cultivation in eastern and north eastern regions of ... shifting cultivation are devastating and far-reaching in degrading the ...
Ecological problems due to shifting cultivation Rajiv Ranjan and V. P. Upadhyay The current practice of shifting cultivation in eastern and north eastern regions of India is an extravagant and unscientific form of land use. The evil effects of shifting cultivation are devastating and far-reaching in degrading the environment and ecology of these regions. The earlier 15–20 year cycle of shifting cultivation on a particular land has reduced to 2–3 years now. This has resulted in largescale deforestation, soil and nutrient loss, and invasion by weeds and other species. The indigenous biodiversity has been affected to a large extent. To mitigate the environmental loss and to provide other alternatives of livelihood to the local population, we have made an attempt in this paper to suggest environmental management options for shifting cultivation areas. THE increase in human population, particularly in the developing countries, has put tremendous pressures on land. The extension of crop lands, for increasing food production, has been directly responsible for the reduction in areas under forests and grass lands. According to one estimate, about 40% of the land surface of the earth was converted into crop lands and permanent pastures by early 1990s (ref. 1). More than 6% area under tropical forests was converted to shifting cultivation between 1980 and 1990 across all tropical countries. About 10% of forest land was converted to shifting cultivation in Asia during the above period 2. On the basis of data given in FAO and other sources, it is estimated that each year approximately 1.9–3.6  10 6 ha land of primary close forests, 3.4–40  106 ha land of secondary close forests, and 6.9–21.9  10 6 ha land of secondary open forests are being lost due to shifting cultivation3. Shifting cultivation is prevalent mostly in tropical countries. In India, the people of eastern and north-eastern region practice shifting cultivation on hill slopes. 85% of the total cultivation in northeast India is by shifting cultivation4. Due to increasing requirement for cultivation of land, cycle of cultivation followed by leaving land fallow has reduced from 25–30 years to 2–3 years. Earlier the fallow cycle was of 20–30 year duration, thereby permitting the land to return to natural condition5. Due to reduction of cycle to 2–3 years, the resilience of ecosystem has broken down and the land is increasingly deteriorating. The paper discusses the shifting-cultivation practices in the eastern and northeastern regions of the country, and suggests certain strategies to revive the deforested areas for achieving ecological sustainability.

The authors are in the Ministry of Environment and Forests, Eastern Regional Office, Bhubaneswar 751 001, India.

Shifting cultivation in Orissa Shifting cultivation is an age-old practice, particularly being practised in the Eastern Ghats. Orissa accounts for the largest area under shifting cultivation in India. Shifting cultivation is locally known as the podu cultivation. About 5298 sq km area annually is under this primitive agriculture practice. About 1.5 lakh tribal families are engaged in podu cultivation5. Based on the task force of Government of India report, more than 30,000 sq km of land (about 1/5 land surface of Orissa) is under such cultivation. Shifting cultivation is prevalent in Kalahandi, Koraput, Phulbani and other southern and western districts, covering 119 blocks (Table 1). The tribal communities, viz. Kondha, Kutia Kondha, Dongaria Kondha, Lanjia Sauras, Paraja, Godaba, Koya, Didayi, Bonda, Jhang and Pauri Bhuyan, Peranga and Erenga Kolha are involved in this practice6. Many festivals and other such rituals revolve around the podu fields, because the tribals view podu cultivation not just as a means of their livelihood, but as a way of life. Podu cultivation is generally on the hills: since land on the foot hills belongs to affluent people; and the valley or plain land, due to water accumulation, increases the chances of damage to crops. In the first year of podu cultivation, tribals sow kandlan (variety of arhar dal). Sowing, by spraying the seeds, is taken up at pre-monsoon time and the area is adequately protected. Yield differs from area to area depending on local climatic factors. After harvest, the land is left follow. During the pre-monsoon, suan (a variety of rice), kangu (a variety of maize) and ginger are also sown. Generally, haldi is sown with kangu and suan: haldi forms the underground crop having economic value, and kangu and suan form the overland crops for consumption. At many

places ginger is raised as the pure crop. At maturity, harvesting of overland crops is followed by harvesting of underground crop. Generally, after the third year, the tribals abandon this land and shift to new land. On the abandoned land, natural regeneration starts from the available root stocks and seed bank. Bamboo comes up naturally; and kendu, mahua, Terminalia along with certain other climbers also regenerate. Generally, this land is not cultivated for the next 10 years. During this

period, tribals use this land to collect root suckers which are used as eatables; mahua and Eleocarpus (Salpa) trees are used for the preparation of liquor for their consumption.

Shifting cultivation in the northeastern states Shifting cultivation is prevalent in all the northeastern states. Tables 2 and 3 present the results of successive studies carried out by the Forest Survey of India, i.e. State of Forest Report, 1995 and 1997. It was noted that loss in forest cover in the northeastern states was mainly due to the shifting cultivation. In the State of Assam, other factors have also been shown to contribute to reduction in the forest cover. Change of forest cover from 1993 to 1997 is given in Table 2. From 1993 to 1995 and 1995 to 1997, loss in forest cover was, respectively, 783 sq km and 316 sq km (Table 3) (refs 7, 8). According to the 1995 and 1997 reports, although 1078 sq km and 1700 sq km areas were gained from the shifting cultivation, they constituted only scurby vegetation. Nevertheless, these growths can also help in checking soil erosion from the hilly slopes which are catchment of a number of streams and rivers of the region.

Impact of shifting cultivation The shifting cultivation is generally practised in the following sequence:  

   

Selecting a forest patch and clear fell the vegetation normally in December and January Burning of the vegetation. Small, cut-trunks portion and roots are normally not removed. The herbs, shrubs and twigs and branches (slashed vegetation) are burnt in February and March Sowing of seeds, by dibbling, generally of cereals, vegetables and oil seeds in April– May Continuing cultivation for a few years Abandoning the cultivated site and shifting to other forest sites Returning to the former site, and once again practise shifting cultivation on it.

With reduction in jhum cycle from 20–30 years to 2–3 years, the land under shifting cultivation looses its nutrients and the top soil. With reduction in crop yield, the families start moving to other virgin areas. Now a stage has come that it has already affected 2.7 million ha of land, and each year 0.45 ha of land fall under shifting cultivation, in northeast India. Frequent shifting from one land to the other has affected the ecology of these regions. The area under natural forest has declined; the fragmentation of habitat, local disappearance of native species and invasion by exotic weeds and other plants are some of the other ecological consequences of shifting agricul-ture. The area having jhum cycle of 5 and 10 years is more vulnerable to weed invasion compared to jhum cycle of 15 years. The area with fifteen-year jhum cycle has more soil nutrients, larger number of species, and higher agronomic yield with ratio of energy output to input as 25.6 compared to jhum cycle of 10 and 5 years (4.6– 9.8) (ref. 10). Similarly, while studying jhum ecology in Meghalaya, it was reported that water and nutrient losses in shifting-cultivation areas were far greater than in the virgin areas,

and areas left for 50 years after jhuming11. Thus, reduction in the cycles of podu, or jhuming, adversely affects the recovery of soil fertility, and the nutrient conservation by the ecosystem. Repeated shortcycle jhuming has created forest-canopy gaps which are evident from the barren hills.

Controlling shifting cultivation: The initiatives and strategies Clandestinely, shifting cultivation is being practised on the Revenue, Reserve Forests and protected forests. Although shifting cultivation is a non-viable resource-utilization practice, tribals are still clinging to this primitive practice to sustain themselves and their families mainly due to non-availability of timely employment avenues. Various attempts have been made by the Government to settle the tribals involved in shifting cultivation. (i) Arable land is provided to the tribals for carrying out agriculture and also to settle in the area; a few schemes are being implemented under integrated tribal development programme in the districts of Koraput, Keonjhar and Phulbani in Orissa. These schemes have however, not yielded the desired results perhaps because of the ignorance of the authorities about the socio-economic and agro-ecological conditions of shifting cultivation and also due to minimal involvement of Forest Department officials, who are more informed about the above factors, in implementation of the scheme. Failure of the scheme led the National Commission of Agriculture to reformulate the schemes only after considering the impact of the forest management. (ii) An Agroforestry project known as Nagaland Environment Protection for Economic Development (NEPED) funded by Canadian International Development Agency (CIDA) through India–Canada Environment Facility (ICEF) was initiated in 1995 to make Nagaland self-sufficient in agro-forestry. The objectives of the project were: (a) identification of trees by local tribes and demonstration of method leading to more sustainable resource management; (b) addressing people’s need, and evolving better management systems; and (c) promoting marketing initiatives. Under this project, experienced Government officials convince the villagers to set aside 6 ha of land, known as test plot, in jhum areas for over two-and-half years. Owner of this plot is required to plant 1200 seedlings, along with usual crop, under supervision of village council and project team. These test plots become open school-cum-research station, as well as demonstration plots to teach new technology. Thus, NEPED project does not aim at eliminating jhum cultivation, but making it more stable and profitable. This novel project may give us a more scientific

way to tackle tribal–forest conflict.

The strategies 1. Providing employment opportunities and income generation on a regular basis through proper utilization of the land resources, i.e. by equitable distribution of waste land among the tribals. But, the various schemes of the Government, under the tribal plan, will have to pump in sufficient resources for proper reclamation and development of the wasteland through agro-forestry and silvi-pasture practices. 2. By encouraging cooperative efforts for carrying out forest-based activities, i.e. basket making, rope making, cane furniture processing of minor forest produce, honey collection, etc. have to be made commercially viable by providing proper marketing facilities. This will not only discourage tribals from practising shifting cultivation but will also help them monetarily. 3. By forming Village Forest Committees for the protection and development of the degraded forests. These committies by providing suitable incentives to the tribals, after the time of harvest can divert some of the tribals away from the shifting cultivation. Generating employment opportunities during the lean season of forestry operations will also prevent tribals from shifting to other areas. Employing the tribals for collection of kendu leaves and sal seeds and also involving the tribals in the various rural employment schemes is also the need of the hour. 4. By ensuring implementation of total literacy campaign; which due to remoteness and un-supportive attitude of tribals, has not been successful. For educating tribal women and children, services of various non-Governmental organizations and voluntary agencies, besides the regular Government machinery, are on required sustainable basis rather than with a targeted approach.

Eco-development plan for areas under shifting cultivation Ecologically, these regions are far worse than realized. Apart from losing vegetation and biomass due to the practice of shifting cultivation, many other ecological factors too have been affected. Due to shifting cultivation practice on slopes, down-stream siltation of the water bodies is apparent in many districts. Protection and repair of drainage basins for conservation of ecological resources including water, need large amounts of financial input. The shifting cultivation areas normally receive moderate to high rainfall. Due to splash forces generated from the rain drops, the erosion of precious top soil occurs. Thus, the major factors which influence the rate of soil erosion are the rainfall, the topography of the terrain, and the kind of vegetation and soil conditions12. The mountain eco-systems of these regions with shifting cultivation practice, have to be made ecologically sustainable. Formulating an eco-development plan for the region for environmental sustainability, could consider completely replacing agricultural practice with farm forestry. Agricultural practices are at the cost of loss of biodiversity resources; estimates indicate that one unit of energy in agronomic production costs loss of greater energy from the forests. However, in the Central Himalayan eco-systems, where agriculture practice is more scientific compared to shifting cultivation, one unit of energy in agronomic production entails an expenditure of about 10–12 units of energy from the surrounding forests as

firewood, fodder and leaf manure12. Loss of energy from the forests per unit of agricultural production may be far greater in shifting-cultivation areas. Farm forestry may be one of the solutions to redress this loss. The advantages of farm forestry area are:12

    

The protective values of trees are far greater than those of annual crops Unlike annual crops which require frequent ploughing, tree plantations cause minimal soil disturbance Net above-ground primary productivity of forests is notably greater than that of agricultural crops and grassland By providing fodder and firewood, the farm forestry would create a favourable situation for the revival of the natural forests A revived forest cover could offer several other advantages.

Determining the population-supporting capacity (PSC) may be one of the major aspects for checking the degradation of environment and depletion of resources13. This study should include not only the food production and land availability but also consider other factors of carrying capacity. The PSC should be based on:   



Land and resource management, in order to restore and improve sustainable yields Prevailing standards of living of the population, in relation to sustainable yields of subsistence materials and changes in technology, innovation and Government policy Flow of trade for food items, rather than for timber, fuelwood and fodder; with emphasis on information on transportation system, administration, natural disasters, regional conflicts in relation to import and export The state of ecological balance and level of exploitation of natural resources13.

The forests surrounding a hill village is considered as ‘support area’ which provide firewood, fodder, timber, water and animal bedding to the people14. The tribal population mainly depends on renewable resources and is not willing to move out of its natural habitat. The PSC study will provide a direction for wise allocation of resources, and change in existing practice of cultivation to achieve higher yields. While examining six models for a hill district of Central Himalayas, it was observed that collection of revenue from forest resources and milk products for purchasing food grains is more economical than cultivating same land for foodgrains13. Per unit produce from forest is much higher than agriculture. In the hills of eastern and northeastern region the above findings can be applied, as the production from these areas under shifting cultivation cannot be increased even by applying modern agricultural practices. Inputs like irrigation facilities, good seeds, fertilizers may prove to be counter-productive due to slope, topography, elevation and other environmental constraints. In case this eco-development plant of farm forestry is taken up, and the tribals discontinue the practice of shifting cultivation, the daily livelihood and income generation avenues for the tribals could be met using the earlier-discussed four strategies. The cooperation of village people, voluntary organizations and the officials of all connected departments should accelerate environmentally sustainable development of resources affected by podu

cultivation practices.

1. 2. 3. 4. 5. 6. 7. 8. 9.

10. 11. 12. 13. 14.

World Resource Institute, World Resource, Oxford University Press, Oxford, 1996. Singh, K. D. and Marzoli, A., Paper presented at the World Wildlife Fund Conference on the Potential Impact of Climate on Tropical Forests, San Juan, Puerto Rico, pp. 2–3. Detwiler, R. P. and Hall, C. A. S., Science, 1988, 239, 42–47. Singh, J. S. and Singh, S. P., Forests of Himalaya, Gyanodaya Prakashan, Nainital, 1992, p. 294. Patro, S. N. and Panda, G. K., Eastern Ghat in Orissa: Environment, Resources and Development, Orissa Environment Society, 1994. Mohapatra, K. and Devi, K., Adivasi, 1973, XIV, 4. FSI, State of Forest Report, Forest Survey of India, Dehra Dun, 1995. FSI, State of Forest Report, Forest Survey of India, Dehra Dun, 1997. Borthakur, D. N., Singh, A., Awasthi, R. P. and Rai, R. N., in Proceedings of National Seminar on Resources, Development and Environment in Himalayan Region, D. S. J., New Delhi, 1980, pp. 330– 342. Misra, B. K. and Ramakrishnan, P. S., Oecologia Applic., 1981, 2, 369–389. Singh, J. and Ramakrishnan, P. S., Proc. Indian Acad. Sci., 1982, B91, 269–280. Singh, J. S. et al., in Eco-Development Guidelines and Model of Development of the Central Himalaya, Department of Botany, Kumaun University, Nainital, 1986, p. 48. Martins, P. J. and Nautiyal, J. C., A case study in the Central Himalayas, paper presented at IUFRO Workshop, New Delhi, 1987. Ashish, S. M., A working paper presented to the task force for the study of eco-development in the Himalayan region, Planning Commission, Govt. of India, New Delhi, 1982.

Received 23 March 1999; revised accepted 6 August 1999

Current Science Volume 77 Number 10, 25 NOVEMBER 1999