An overview of shifting agriculture (Jhum) in Eastern Himalayan Region as a component of village landscape

· Articles
Authors

T. SHIMRAH1 *, R.K. MAIKHURI 2, K.S. RAO3 & K.G. SAXENA4

1University School of Environmental Management, GGSIP University, New Delhi 110 078,
2G.B. Pant Institute of Himalayan Environment and Development, Garhwal Unit, P.Box. 92, Srinagar (Garhwal)
3Department of Botany, University of Delhi, Delhi 110 007
4School of Environmental Sciences, Jawaharlal Nehru University, New Delhi 110 067
*Corresponding author: T. Shimrah; tsshimrah@gmail.com.

Abstract

Shifting agriculture, locally known as ‘Jhum’ in north eastern part of India is one of the main components of village agroecosystem. It is subjected to various kinds of criticism such as the main cause of forest degradation and subsequent ecological imbalances in the region, apart from low productivity and economic returns to the farmers. But even all forms of agriculture taken as a whole in this region, it is a still a minor land use in terms of spatial extent (net sown area being < 20% of total geographical area). In term of dependencies by the traditional communities in Northeast India on shifting agroecosystem, it is the backbone of local livelihoods and ecosystem services. It is rather one of the complementary land uses in a larger frame of integrated ecosystem consisting of wet paddy cultivation, plantations and forests. Shifting agriculture practice involving controlled logging and limited extraction of biomass is sustainable in term of species regeneration and rejuvenation of forest.

Keywords Shifting agriculture, Forest, Northeast, Landscape, Local communities, Arunachal Pradesh

Introduction

Himalayan mountain system (partly/fully covering eight countries of Asia viz., Afghanistan, Bangladesh, Bhutan, China, India, Myanmar, Nepal and Pakistan) contiguous with Montane Mainland of South-east Asia (covering six Asian countries viz., Cambodia, China, Laos, Myanmar, Thailand and Vietnam) is a socio-economically marginal region but globally distinguished for a huge biodiversity, its far reaching environmental influences (Himalayan hill ranges determining monsoon patterns and water flow patterns in river systems supporting livelihood of millions of people in south Asia) and an extremely rich indigenous knowledge on livelihood-environment relationships accumulated by hundreds of local communities isolated by terrain and linguistic barriers for centuries. Agriculture in this region is a minor land use in terms of spatial extent (net sown area being < 20% of total geographical area) but is the backbone of local livelihoods as well as a key factor determining global benefits from Himalayan biodiversity and ecosystem services. Quite a few efforts have been made to characterize the spatiotemporal dynamics of forest/ agricultural land use (Saxena et al., 1993; Rai, 1995; Rao and Pant, 2001; Semwal et al., 2004; Behera et al., 2002, 2005) and to compare ecological/economic efficiency, plant community structure and composition, and soil properties of selected agricultural/forest ecosystems in different parts of the Himalaya (Sharma, 1991; Ramakrishnan, 1992; Semwal and Maikhuri, 1996; Ralhan et al., 1991; Singh, 1992; Singh et al., 2008).

Traditional agriculture has often been criticized for a low productivity and profitability. Further, this land use invariably dispersed as ‘patches’ in the ‘matrix’ of forests, is commonly viewed as the root cause of forest fragmentation and associated loss of natural resource capital. Such perceptions led to policies that discouraged traditional land uses through legal enforcements or through economic incentives to people for adoption of modern intensive agro-technologies. Recent studies however suggest that the so called ‘traditional low tech’ systems may not necessarily be less productive than the ‘modern high tech’ systems (Shriar, 2000) and promotion of intensification may accelerate deforestation rates if effective conservation policies are not in place (Pichon, 1996). Further, many traditional varieties may have lower yields but receive price-premiums for their high quality compensating for lower yields (Smale et al., 2004). In a state of knowledge clouded with divergent views and conclusions about what is (are) scientifically the ‘best action(s)’ for achieving sustainability or the conclusively established criteria and indicators of a landscape resilient to environmental and economic stresses and uncertainty, policy actions have been drawn and implemented to achieve sustainable land management across the world (Lesterlin and Giordano, 2007).

Thus, there is a need of enhancing our knowledge for designing policies enabling sustainable development based on sustainable land management. A comprehensive understanding of land use differentiation in village or cultural landscapes and its implications (Ramakrishnan, 1992; Angelsen, 1995; Lefroy et al., 2000) is required for promoting sustainable land management in mountain regions.

The concepts of sustainability and sustainable landscapes

The concept of sustainability has been explained in a variety of ways. Characterisation of sustainability concept is essential when aims are to use it to identify constraints, to identify research foci and for policy development and translating the science of sustainability in actions for sustainable development or sustainable livelihood essentially means applying long term and interdisciplinary perspectives, in regard to human well-being and ecological integrity, to policies and actions (Hansen, 1996; Walker and Schulze, 2008). Conway (1987) viewed sustainability as the ability of an agroecosystem to maintain productivity when subject to a major disturbances such as a severe drought or a decline in market demand. Sustainability can be explained in terms of ability of ecosystems to maintain basic structure and function during perturbations, and to recover from them referred as resilience (Kasperson et al., 1995). Lynam and Herdt (1989) defined sustainability as the capacity of a system to maintain output at a level approximately equal to or greater than its historical average. Hainnes-Young (2000) defined sustainable landscapes where deforestation rates are low, or with no net forest loss or even expansion of forest cover, and where multiple institutional processes efficient in preserving the ecosystem integrity are in place. Perz and Skole (2003) viewed sustainable landscape as the one where rate of deforestation is and likely to be < 1% together with land use tendencies favouring forest recovery rates exceeding the deforestation rate. Long term data on crop yields, life quality, ecosystem processes, land use changes and frequency/intensity of disturbances are required to arrive at any meaningful conclusion on the magnitude of sustainability/unsustainability of a system in the past. Such data bases are lacking. Furthermore, available scientific tools are too weak to predict climatic events, such as the onset of monsoon and occurrence of heavy downpour and hail storms or biological events such as gregarious bamboo flowering coinciding with an abrupt rise in rodent population, which have significant impacts on performance of biological production systems. The conclusions on high or low sustainability of production systems are thus often subjective individual assessments which may be questioned for their scientific validity.

Serrao et al. (1996) explained sustainability in terms of the notions of environmental endangerment (when environmental degradation threatens continuation of human use in both the short and mid-run, more specifically current and next generation) and impoverishment (when long-run human use and welfare are threatened). Subjectivity is inherent in delineating the system in space and time and setting the threshold values of the rates of environmental and economic processes or of resource capitals needed for sustainability of the system. For example, 2-11 t/ ha/yr of soil erosion or maintaining forest cover over at least 2/3rd of total geographical area are commonly taken as the requirements for sustainability in mountains but scientific validity of these limits may be questioned. Occurrence of multiple and inter-linked land uses point to consideration of sustainability not of a specific land use but of the whole landscape (Lynam and Herdt, 1989). An analysis of differentiation of ecosystems in selected village landscapes in Arunachal Pradesh in eastern Himalaya and the interventions needed for sustainable landscape management are dealt below.

Ecosystem differentiation in village landscapes in Arunachal Pradesh

Two village landscapes around Dehang Debang Biosphere Reserve viz., and Yogong are located in East/ West Siang district of Arunachal Pradesh and spread over an elevation range of 1600-1800 m amsl on 300 to 400 slopes were selected for detail analysis. Yogong village is smaller in size (in terms of population) and highly inaccessible compared to the Domong village. Population increased by 86% in village Domong and decreased by 37% in village Yogong (Table 1). Yogong village landscape thus represents a low population-traditional village landscape and Domong a high population-transitional village landscape.

Table 1. Human population changes over 1970/75-2006 period in settlements differing in terms of accessibility (Shimrah et al., 2007)

Domong – easily accessible village

Yogong – highly inaccessible village

Number of families during 1970-75

140

57

Number of families during 2006

260

36

Rate of increase/decrease in numberof families

+86%

-37%

Population during 1970-75

950

416

Population during 2006

1759

216

Rate of increase in population

+85%

-48%

Number of families migrated fromoutside the village during 1970-75-2006 period

10

nil

The climate is sub-tropical humid with mean annual maximum and minimum temperatures of 29 and 180 C, respectively, and annual rainfall of 2400 mm. The year consists of three seasons: June to October – a warmhumid period, November to March – mild winter and April-May – dry summer season. About 90% of total annual rainfall is received during June to October. Soils are highly leached sandy-sandy loam with laterite as the dominant parent material. There is no cadastral map even now in the selected villages, as also in most villages in the north-east India. Natural features such as hill tops, streams and rivers constitute the boundaries of traditional village territories.

Based on rapid participatory survey and satellite imagery interpretation, we deduced basic features of land use and holdings. Unlike Yogong where all land is privately owned, 80% of Domong village land is privately owned and 20% by the community. All shifting agriculture areas are treated as family lands unlike Meghalaya and Manipur where such areas are owned by the community, with cultivation rights granted to individual families by the village councils based on an assessment of subsistence requirements rather than income aspirations. In Domong village, even the river passing by the village is divided into segments, with family-wise rights of fishing and stones/sand collection. The practice of buying/selling of land/river resource rights, though legally not permitted, is gradually coming up. Domong village had mean land holding of 19 ha and livestock holding of 11 animal units compared to 211 ha and 16 animal units in Yogong village (Table 2). Secondary data sources reveal land holding size varying from from 35 ha to 145 ha. Considering that 7 ha of land per person is required for sustainable livelihood as worked out by Toniolo and Uhl (1995) for Eastern Amazon, land is not yet scarce in the study area as also in some parts of Malaysia (McMorrow and Talip, 2001).

Table 2. Land holding size (ha) in selected village landscapes in Arunachal Pradesh (Shimrah et al., 2007)

Most easily accessible villages

Most inaccessible villages

Range

Mean

Range

Mean

Wet paddy cultivation

0.0 to 0.5

0.12

0.2 to 1.2

0.66

Jhum – cropped area

0.1 to 1.5

0.60

0.03 to 0.3

0.12

Jhum – fallow area

1.0 to 9.0

4.78

1.0 to 6.0

2.97

Plantations

0 to 6.0

3.61

Nil

Nil

Forests

1.0 to 18.0

9.54

50 to 350

208

Total

5.0 to 20.0

18.79

50 to 360

211.44

Land use land cover maps were prepared from digital interpretation of Landsat TM data of 1988 and IRS P6 data of 2004. Five types of major land use classes are differentiated in the village landscape: cropped fields under Jhum, fallow fields, tree plantations in fallows, forests, and sedentary wet paddy cultivation in valley (Figure 1). Relative area under shifting cultivation and wet paddy cultivation (locally referred to as Jhum and Pani Kheti, respectively) depends upon the hydro-geo-morphological setting of the landscape: more the availability of land suitable for wet paddy, lesser the area under shifting cultivation. However, tree plantations in Jhum fallows were observed only in easily accessible Domong village.

Cropping under shifting agriculture

Jhum involves 1-3 years of cropping followed by 6-8 years of fallow period. Climbers/herbaceous vegetation are cut down by women followed by tree cutting by men in the area selected for Jhum. In village Domong, some of the bigger trunks are taken away to meet local subsistence needs and some sawn and exported for income. On the other hand, in village Yogong, wood is not removed and the partially burnt large trunks are put across the slope to reduce soil loss as well as to demarcate field boundary. After establishing a fire line (removal of all inflammable biomass in 1-2 m wide clear-strip around the Jhum plot), fire is set such that it advances downwards. Differing from the Mayans who do not cut a tree like Orbignya cohune for its ability to resist fire once the lower leaves are removed (Levasseur and Olivier. 2000) or some Naga tribes who do not cut Alnus nepalensis for its soil fertility enrichment values (Ramakrishnan, 1992), people in the present case cut all trees except the large individuals of Morus laevigata, Terminalia myriocarpa, Duabanga grandiflora and Altangia excelsa for high economic value of their timber. Jhum is characterized by a mixed crop, with harvesting of maize, millets and pumpkins in August/September and chilly and paddy in November/ December. During the second/third year of cropping, the undecomposed aboveground crop residues are piled up in patches and ash-rich microsites created following burning of residues are sown with mustard. After burning, a plot was cropped for 3 years followed 7-8 years of fallow period in Domong village compared to 2 years of cropping and 9-10 years of fallowing in Yogong village (Table 3). Rice yield (2110-3257 kg ha-1) under shifting agriculture in the present study areas in Arunachal Pradesh characterised by 6-8 year long cultivation cycle was markedly higher than the yields of 66, 378 and 1161 kg ha-1 under 5, 10 and 30 year cultivation cycles, respectively, in Meghalaya (Toky and Ramakrishnan, 1981), 700-4530 kg ha-1 in 7 year rotation cycle in northern Thailand (Yimyam et al., 2003) and 1504 kg rice ha-1 (+1238 kg millet ha-1 and, 910 kg beans ha-1) reported in Latin America (Cowgill, 1962; Morley, 1975).

Table 3. Crop yields (mean and SE) in shifting agriculture in Domong and Yogong village landscapes (Shimrah et al., 2007)

Most easily accessible villages

Most inaccessible villages

Jhum-1st

Year

Jhum-2nd

Year

Jhum-3rd

Year

Mean

Jhum-1st

year

Jhum-2nd

year

Mean

Paddy

3257 ± 276

2788 ± 197

2375 ± 126

2807

2786 ± 286

2110 ± 177

2448

Maize

262 ± 31

200 ± 85

172 ± 85

211

198 ± 57

273 ± 63

236

Millet

72 ± 71

90 ± 89

NG

54

3483 ± 366

198 ± 174

1841

Mustard

488 ± 144

390 ± 156

247 ± 106

375

257 ± 116

112 ± 66

185

Cucumber

413 ± 149

359 ± 213

317 ± 47

363

392 ± 112

212 ± 146

302

Brinjal

259 ± 43

192 ± 29

226 ± 32

226

115 ± 33

135 ± 20

75

Chilly

123 ± 64

167 ± 57

198 ± 34

163

217 ± 27

142 ± 14

180

Garlic

57 ± 27

15 ± 15

25 ± 25

32

42 ± 26

NG

21

Bitter brinjal

259 ± 43

192 ± 29

193 ± 19

215

125 ± 35

135 ± 19

130

Ginger

NG

90 ± 39

16 ± 16

35

100

100

100

Coriander

10

10

10

10

NG

NG

NG

Beans

20

20

20

20

28

28

28

Colocasia

100

100

100

100

45

45

45

Sweet potato

NG

100

100

67

NG

NG

NG

Sesame

NG

35

35

23

NG

NG

NG

Ochra/lady’s finger

NG

NG

NG

NG

37

37

37

Wet paddy cultivation in valley

Rice production in wet paddy cultivation in valleys is about 1.3-1.5 times higher as compared to that in Jhum cultivation possibly due to enrichment of soil from nutrient wash out from the surrounding slopes, decomposition of all crop residues within farm fields, amelioration of water stress and cultivation of paddy monocrop in the valley system. Though the potential rice yields in valley land is high, there is a risk of delayed monsoon as the traditional paddy varieties grown fail to perform under such climatic condtions.

Compared to the yield range of 2848–5490 kg ha-1 in the present study (Table 4) in relatively isolated landscapes, Toky and Ramakrishnan (1981) reported an yield of 3710 kg ha-1 yr-1 (from two paddy crops in a year) and Kumar and Ramakrishnan (1990) of 3456 – 4064 kg ha-1 yr-1 (one crop a year) in less isolated landscapes significantly influenced by external agents in the northeastern India. At some locations, where three paddy crops are harvested in a year, annual edible yield may be as high as 8000 kg ha-1 yr-1. Such high yields in the absence of any external inputs highlight the untapped potential of local cultivars and associated indigenous knowledge. Yet these yield levels are far below the level of 15 t ha-1 reported for the System of Rice Intensification (Stoop et al., 2002). Farmers maintain considerable local crop diversity in the form of traditional varieties and genetic complementarities of the varieties can buffer against extreme climatic events and pests and diseases, replacing the role of crop species diversity in shifting agriculture (Reusch et al., 2005). Crop genetic as well as species diversity in rainfed upland agriculture is substantially higher than that in irrigated valley agriculture (Gauchan and Smale, 2007). Our studies on niche divergence and variety-environment relationships in wet paddy systems in the study area are yet to be concluded.

Table 4. Rice yield (kg ha-1); mean and standard error) in wet paddy cultivation (Shimrah et al., 2007)

Easily accessible/lower elevation villages

5490 ± 466

More inaccessible/higher elevation villages

2848 ± 193

Forests

Unlike the central and western Himalayan regions of Indian Himalaya inhabited by settled farming communities, where the government took over all well stocked forests long back in the 1870s, such a change in ownership has been effected only in the 1970s, that too over a smaller area, in the north-eastern Himalaya inhabited by shifting cultivators. Indian Forest Act, 1980 has been a very crucial legislation that restrained conversion of forest land for non-forestry purposes. More than 70% forest area in the State of Arunachal Pradesh remains under the control of local communities. There is a significant difference in the notified area and actual computed area of government reserve forests due to lack of proper survey as well as non-fixation of boundaries on ground. Further, continuation (but not expansion) of cultivation and forest resource utilization (including hunting and fishing) to meet local needs was allowed with an understanding that people will protect government forests from outsiders (Give reference of the Working Plan). Though extent of cultivation area has not been demarcated or defined, it is very often assumed that cultivated area might have increased due to non-fixation of the limits of cultivated area and increase in the population. Since 1970s, the Government started giving permits of timber extraction in unclassed forests to contractors and in Reserve Forests to industries. Timber was supplied to local saw mills which exported finished or semi-finished products till 1983 when the export was banned. This resulted in a sharp growth of wood based industries within the State. Bamboos are present in huge quantities but have not been intensively extracted because of absence of paper and pulp industries. Canes have been utilized to a significantly greater extent. A large number of medicinal plants are found in these forests but this resource base has been, by and large, used only for local health care. A public interest litigation in 1995 led to ban on all fellings and even removal of deadwood by all including government agencies as long as a systematic forest working plan was not prepared. This interference led to classification of government forests into : (a) Protection Working Circle where no forestry or felling activity is permissible (b) Selection Working circle (also referred as selection cum improvement felling circle) where – trees with girth > 210 cm are utilized under 25-year-long felling cycle (c) Conversion Working circle including activities such as afforestation of open areas and conversion of forests of low economic value to more valuable forests (e.g., ‘conversion to uniform system’ involving clear felling followed by artificial regeneration with locally available important species) (d) Plantation Working circle (e) Minor Forest Produces Working Circle where a 4 year-cutting cycle has been prescribed for utilization of canes. Such classification and management practices have not yet come up for the forests owned by the local communities.

Recently, India has enacted a legislation (The Scheduled Tribes and Other Traditional Forest Dwellers (Recognition of Forest Rights) Act, 2006 to recognise and vest the forest rights and occupation in forest land in forest dwelling Scheduled Tribes and other traditional forest dwellers who have been residing in such forests for at least three generations prior to the 13th day of December, 2005 and who depend on the forest or forests land for bona fide livelihood needs but whose rights could not be recorded. The forest rights, heritable but not alienable or transferable, shall be conferred free of all encumbrances and procedural requirements, including clearance under the Forest (Conservation) Act, 1980, requirement of paying the ‘net present value’ and ‘compensatory afforestation’ for diversion of forest land, except those specified in this Act. All forest right holders are empowered and expected to ensure adequate protection of the wild life, forest and biodiversity, watershed/ecosystem functions and indigenous culture and natural heritage, with directives issued by the concerned village community. Notwithstanding anything contained in the Forest (Conservation) Act, 1980, the Central Government shall provide for diversion of forest land for some government managed facilities requiring felling of trees not exceeding seventy-five trees per hectare, such as schools, dispensary or hospital, fair price shops, electric and telecommunication lines, minor water bodies, rain water harvesting structures and drinking water supply, minor irrigation canals, non-conventional source of energy, skill upgradation or vocational training centres, roads and community centres, provided that such diversion of forest land does not more than 1 ha of forest land and felling of trees more than 75 trees per ha and such development activities are accepted by the concerned village communities. This recent Indian legislation is partly similar to that implemented in Milpa region in Mexico in 1992 giving local communities an option of privatizing their inalienable community lands. However, while the Indian legislation anticipates enhancement of local livelihoods together with forest conservation as an outcome of privatization, the Mexican one anticipates mobilization of private investment, development of land market and productivity gains in agriculture (Chowdhury and Turner, 2006). As stated by Hardin (1998), individualism is cherished because it produces freedom, but the gift is conditional: the more population exceeds the carrying capacity of the environment, the more freedoms must be given up; property regime is one and not the only factor determining sustainability (Fratkin, 1997; Moxnes, 1998).

Shifting agriculture: an element of village landscape

Perceptions on the role played by shifting agriculture on ecosystems integrity at the landscape scale are divided between: (a) those proposing loss of biodiversity and habitat fragmentation due to this practice (Smith et al., 1999; Gupta, 2000; Raman, 2001) and (b) those suggesting improvement of ecosystem diversity due to juxtaposition of patches of farmlands in different stages of cultivation and forest succession cycles (Gregory et al., 1991; Yavitt et al., 1995; Oba et al., 2002), absorption of labour which has a low opportunity cost (Cramb, 1989) and a very rich social and human capital arising from indigenous knowledge about shifting agriculture (Ramakrishnan, 1992; Cramb, 1993; Nautiyal et al., 1998). These divergent opinions partly derive from the methods adopted to quantify the area, land use intensity and land use-land cover monitoring (McMorrow and Talip, 2001). Shifting cultivation is so diverse a system that it grades into several other land use-land cover classes with overlapping spectral characteristics and hence may not be precisely mapped using remote sensing data. Scope of using satellite data for quantifying land use-land cover changes in tropical humid mountain regions get further limited by availability of data over the periods when sun elevation is high (i.e., less shade effect). Land use-land cover changes over 1990-2004 period deduced from interpretation of satellite data supplemented by intensive ground surveys (Table 5,6) indicate a significant conversion of highly dense and diverse natural forests to shifting agriculture and other land uses. The nature and intensity of changes dramatically vary. After a village became easily accessible, population increased but the rate of increase in population (86%) was higher than that in the area under shifting agriculture and related land uses, e.g., fallows converted plantations (53%). In the village, which remained highly inaccessible, population declined by 48%, with a decline in area under agriculture by 10%?

Table 5. Land use-land cover changes over 1970-75-2006 period based on participatory survey and mapping in an easily accessible village (Domong) (Shimrah et al., 2007)

Past land use – land

cover (as in 1970-75)

Present land use-land cover (as in 2006)

Jhum

Plantation

Wet paddy

cultivation on

terraced slopes

Wet paddy

cultivation in

valley land

Forest

Jhum – 66 (43%)

48 (73%)

15 (23%)

3 (5%)

0

0

Plantation – 5

0

5 (100%)

0

0

0

Wet paddy on terracedslopes – 0

0

0

0

0

0

Wet paddy n in valleyland – 3

0

1 (33)

0

2 (67)

0

Forests -79

31 (39%)

9 (11%)

1 (1%)

0

38 (48%)

Table 6. Land use/cover changes over 1970/75-2006 period based on participatory survey and mapping in a highly inaccessible villages (Shimrah et al., 2007)

Past land use – land cover Present land use – land cover

Jhum

Wet paddy onslopes

Forests

Jhum – 22

20 (91%)

2 (9%)

0

Wet paddy on terracedslopes – 0

0

0

0

Forests – 47

0

0

47 (100%)

Wet paddy cultivation invalley land – 15

0

0

15 (100%)

Wet paddy cultivation invalley land – 15

0

0

15 (100%)

Mere co-occurrence of shifting agriculture and high deforestation rates (> 90 % forest cover loss in some regions of Costa Rica and Indonesia after 1935) (Imbernon, 1999; Connes et al., 2000) does not mean that the former is the cause and the latter the effect. People view shifting agriculture, wet paddy cultivation, plantations and natural forests as integrated and complementary land uses rather than considering one land use superior to the other(s) in all respects (Table 7). Higher land and labour productivity from agricultural plots derived from secondary forests than from old growth or virgin forests (Silva-Forsberg and Fearnside, 1997) is a restrain on conversion of primary forests as long as shifting agriculture is a part of subsistence economy. Loss of forest biodiversity and ecosystem services in recent times seems derive more from logging for meeting national/regional economic/ industrial needs ignoring the development aspiration of local people, weak institutional arrangements to implement sustainable forest management practices and policy interventions encouraging aggregation of traditional dispersed populations (e.g., government provides access by road, medical facilities, schools, local self-government if population of village is larger than 500) than from increase in population and traditional land uses (Dvorak, 1992; Turner et al., 1993; Lawrence et al., 1998; Albers and Goldbach, 2000; Metzer, 2002).

Table 7. Differentiation of the two major traditional agroecosystems in Arunachal Pradesh based on sustainability concerns of people (Shimrah et al., 2007)

Wet paddy cultivation

Shifting agriculture

Plantations

Natural forests

Remarks

Staple food security

Major

Minor

Minor

Minor

Only paddy is grown in irrigated valleys and yield is substantially higher than in Jhum
Protein and other nutrition

Minor

Major

Minor

Minor

A mixed crop is raised in Jhum field
Health care

Minor

Minor

Minor

Major

High returns from land

Major

Minor

Major

Minor

Total annual gains (in food energy or monetary currency) in the most intensive traditional wet paddy cultivation (harvesting of three crops in a year or integrated paddy-fish farming) is substan- tially higher than that from shifting agriculture
High returns from labour

Minor

Major

Major

Minor

Wet paddy cultivation is more labor intensive as compared to shifting agriculture
Risk of delay in onset of monsoon

Major

Minor

Minor

Minor

Sowing time and cultivars in Jhum are such that yields are not as much affected by delay in mon- soon as in wet paddy cultivation.
Risk of increase in ro- dent population following bamboo flowering

Major

Minor

Minor

Minor

Wet paddy fields are not as suited to rodents as Jhum fields.
Risks of landslides

Minor

Major

Minor

Minor

A buffer zone is maintained around wet paddy fields so as to reduce the sediment load in incom- ing water.
Risks of high rainfall events/flash-floods

Major

Minor

Minor

Minor

All run-off accumulates in wet paddy fields. Very high inflow rates are often beyond the local man- agement capacity.
Risk of fire

Major

Minor

Minor

Minor

Fire is used as a management tool only in Jhum lands and wet paddy fields in valleys are usually at a distance from them.
Risk of crop depredation by wildlife

Major

Minor

Minor

Minor

Jhum fields are more close to forests and provide more suitable habitats to wildlife as compared to wet paddy fields.

Shifting cultivation influences and is influenced by other land-use/cover types in the landscape. Thus, sustainability of landscape including the livelihoods of associated people matters more than that of shifting cultivation as an independent landscape element (Cramb, 1993). If economic diversification is viewed as a means of spreading the risks of environmental unpredictability and variability (Walker et al., 1994), distinctions between shifting cultivators and loggers may be somewhat artificial. Some deforestation is necessary for agricultural development but a sizeable component of the current rate of conversion is due to an excessive intrusion of market forces often promoted by policies (Serrao et al., 1996). Chazdon (2003) suggests that only a mosaic of old-growth forest fragments, secondary forests, logged forests and agricultural fields is likely to protect the regional biota. Biodiversity conservation goal thus is not going to be achieved if logging and shifting agriculture are altogether abandoned. Bamboo, Livistona jenkinsiana and trees that form bulk of the traditional housing structures, are early-mid successional or light-loving species implying that canopy openings are necessary for livelihood. In the traditional resource uses, only small scale openings are created unlike larger openings in commercial loggings. Linear-lognormal species-area relationships are observed in all land use-land cover types, but with higher rates of increase in species richness with increase in area in natural forests compared to fallows (Figure 2). There is a mild gradient in change in species composition in the cultural landscapes (Figure 3). High species diversity in cultural landscapes is explained by a high degree of habitat variability and heterogeneity (Duelli, 1992, 1997; Waldhardt et al., 2004 ).

    

The farming systems of indigenous people, practiced at low population densities and with indigenous ecological knowledge, are thought to be relatively sustainable as compared to the land uses adopted by the migrants (Posey and Balee, 1989; Moran, 1990). Farmers evaluate a given land use in multiple terms: productivity, production efficiency (rate of returns to inputs), product diversity, adaptations to prevailing water and nutrient regimes, climatic unpredictability, ecological functions (e.g., recharge of springs and protection of rivers from excessive nutrient and sediment inflows) and marketing potential (Table 7). In Arunachal village landscapes, shifting agriculture is the traditional land use unlike a response to market opportunities or management constraints as reported in Garhwal Himalaya (Nautiyal et al., 1998). In this region, farmers’ responses to changes, such as population growth, land scarcity, improvement in accessibility, emerging market demands for traditional products and new opportunities of off-farm income, include wet paddy cultivation on terraced slopes (a minor land use) in traditional Jhum area and plantation of economically important species such as Livingstona jenkinsiana (Toko palm), bamboos, oranges in Jhum fallows. These trends also demonstrate farmers’ innovations of ‘development through diversification’. Traditions favouring exchange of healthy seeds free of any cost, allowing shifting agriculture to meet local food needs (but not for maximization of income), disallowing shifting agriculture in environmentally critical areas, e.g., riparian areas, steep slopes and forests around springs and of undertaking agriculture as a cooperative occupation are the elements of socio-cultural capital fostering sustainability in the landscapes dealt here (Walker et al., 1993, 1994; Rao and Saxena, 1996; Connes et al., 2000; Saxena et al., 2001). Conversely, breaking down of these traditions may raise modern economic wellbeing but only over a short term period and by incurring a huge environmental cost (Semwal et al., 2004; Wakeel et al., 2005).

While sustainability of landscapes in the face of changing human and biophysical factors in future is difficult to predict, some conjectures can be made based on comparison of ‘high population-more accessibilitymore influence of market’ scenario in Domong village and ‘low population-poor accessibility-less influence of market’ in Yogong village. It is evident that (a) local production based food self-sufficiency is the prime goal for agricultural land use, (b) low input/organic traditional agroecosystems are able to ensure food security indicating success of indigenous innovations in meeting the growing/ changing food demands, (c) people tend to meet their economic development aspirations not by extensification of agriculture or exploitation of forest resources but through environmentally benign pathways such as improved management of fallows and utilization of non-timber forest products and (d) the ecological capital in village forests in terms of tree diversity and basal area (a surrogate of carbon stock) in some cases are substantially higher as compared to many other shifting agriculture areas (Khan et al., 1987; Ramakrishnan, 1992; Maikhuri et al., 2000; Bhuyan et al., 2003; Tiwari, 2005; Nath et al., 2005). Development interventions such as supply of food grains at subsidized price, economic incentives for tree plantations in Jhum and subsidy on modern agricultural inputs seem to address the problems which do not exist and to discourage processes favouring enhancement of social capital (Table 8). As government agencies tend to project the positive and suppress the negative outcomes of policy interventions (e.g., people are rarely informed that subsidy can be reduced/withdrawn or that market demand/price is unpredictable), threats of unsustainability in future may derive from policy failures (e.g., withdrawal of subsidy on modern agricultural inputs at a time when local cultivars no more exist). Variants of shifting agriculture across the globe could be characterized in terms of a common parameter, the land use intensity or cropping frequency as illustrated in Table 9 and characterization may enable useful cross-regional comparisons.

Table 8. People and government responses to risk and perturbations and their sustainability implications (Shimrah et al., 2007)

Risk/perturbation/government

Intervention

Coping mechanism/impact

Climatic variability and extremes: too low in intensity and frequency to influence crop yields/property to a significant level • Maintenance of a farm drainage system as a community task• Diversification of crops/cultivars and land use systems• Protection of forests around springs and rivers• Maintenance of Jhum area common to a group of villages where    cultivation is permissible if a family suffers serious losses in its own  land
Gregarious bamboo flowering: tremendous increase in rodent population and likely damage to crops, more so of rainfed Jhum crop • Diversification of agricultural land use• Storage of staple food required for two years at least• Traditional storage devices providing safety from the rodents• Mass scale cutting bamboos in the likely during flowering year
Fire risk: spread of fire beyond Jhum • Managing downward advancement of fire• Removal of resin rich material from Jhum site (e.g., pine wood)• Creation of fire line around Jhum plot• Tradition of group action for setting and managing fires
Wildlife depredation of crops:loss of Yields • On-field temporary huts and physical presence of some family members• Use of fecal matter pastes as deterrents to ungulate/pig attacks
Increase in population pressure: agricultural land use expansion and intensification, changes in food habit Stage I• Agricultural extensificationStage II• Change in food habit – reduction in use of rice and millets used for traditional liquour preparation• Replacement of cultivars/crops (black rice and millets) valued for liquorpreparation by those valued as staple food• Wet paddy cultivation on terraced slopes where irrigation potential andcapacity for irrigation management exist• Plantation of fruit and timber trees in fallow landsStage III• Agricultural extensification and intensification stressing on ‘maximumpossible yields and profits’ ignoring the likely environmental risks –

confined largely to pockets where government aid following risks is more

secured

Outcomes arising from Government interference – extraction of timber from forests • Changes in forest species composition/loss of biodiversity• Emergence of new employment opportunities but at the cost of increased inequity in average family income as only a few powerful individuals are able to take up the new occupation• Erosion of socio-cultural traditions favouring utilization of non-timber forest products together with restrictions on use of timber required to meet essential subsistence needs
Outcomes arising from Government interference – take over of natural forests by government and incentives for plantation of timber trees in Jhum land • Changes in traditional village landscape structure and function• Reduction in length of cultivation cycle• Removal of logs before burning the slash• Invasion of alien species and other ecological changes• Increased vulnerability of trees to pests and diseases due to uniform age and species composition
Outcomes arising from Government interference – subsidy on high yielding varietyof wet paddy and chemical fertilisers • Reduction in traditional diversity of wet paddy• Uncertainties and risks due to use of chemical fertilizers• Reduction in area under Jhum, increase in area under wet paddy and yield losses due to peak floods around river courses• Erosion of indigenous initiatives for incremental improvements in traditional farming• Stress on maximization of profits over sustainability of agriculture
Outcomes arising from Government interference – supply of staple food grains atsubsidized price • Erosion of traditional practices fostering local production based foodself-sufficiency• Stress on maximization of profits over sustainability of agriculture

Table 9. Some examples of calculation of cropping frequency in shifting agriculture (Shriar, 2000)

Cropping/agricultural system

Simplification

Calculation of cropping frequency

1/2 : 8 crop fallow cycle, i.e., cropping phase of two years and one crop harvested in each year and fallow phase of 8 years 1 crop harvested in a year followed by 4 years of fallow; crop+fallow period = 5 years Cropping frequency = 1/5 = 0.2
1/3 : 15 crop fallow cycle, i.e., cropping phase of 3 years and one crop harvested in each year and fallow phase of 15 years 1 crop harvested in a year followed by 5 years of fallow phase; crop + fallow period = 6 years Cropping frequency = 1/6 = 0.16
2/1 : 0 crop fallow cycle, i.e., two crops harvested in a year and no fallow phase Crop + fallow phase = 1 year and two crops harvested in a year Cropping frequency = 2/1 = 2
2/2 : 7 crop fallow cycle, i.e., cropping phase of two years and two crops harvested in each year 4 crops harvested in two years; cropping + fallow period = 2+7 = 9 years Cropping frequency = 4/9 = 0.44
30% of cultivated area with cropping frequency of 0.2 and 70% with cropping frequency of 0.5   Overall weighted cropping frequency = 0.2 x 0.3 + 0.5 x 0.7 = 0.6 + 0.35 = 0.41

Forestry vs shifting agriculture

Often dependence on non-timber forest products (NTFP) is argued to be a more sustainable livelihood option than that on timber as utilization of the former accompanies negligible disturbances compared to the latter. However, the land area required for securing livelihood from NTFPs alone may be too large to sustain the present population density. For example, an area of 420 ha per person may be required for continuous extraction of resin from Manilkara zapota (source of chewing gum) in Brazil. Compared to this, an area of 20 ha of forests is required if a family has to meet its requirements through shifting cultivation (Bray et al., 2004). Our studies also show that income from NTFPs permissible in the present policy set-up is too low to secure livelihood (Rao et al., 1996) and an area of about 25 ha will be needed to secure livelihood from shifting agriculture. Interventions such as raising rubber plantation or selective logging and value addition to raw material directly benefiting local people may release substantial area from human use but, at the same time, will make farmers dependent on external assistance (in terms of both financial capital and knowledge) and add the risks of vulnerability due to pest/disease outbreak and downfall in market price (Dove, 1993; Lawrence et al., 1998; Ekins, 2003; Bray et al., 2004). A sequence of policy interventions – introduction of timber extraction on a commercial scale and export of semi finished timber in 1970 and its continuation till 1983, continuation of timber extraction but ban on export of raw or semi-finished products during 1983-2001 period and termination of all timber extractions (including removal of deadwood) thereafter – reflects a high degree of uncertainty in what policy intends to deliver. This uncertainty may lead to non-confidence of people in the government and peoplegovernment conflicts and hence need to be addressed through scientific endeavours.

Conclusions

Most of the studies on land use/cover changes in the tropics reveal one of the following trends: (i) large scale deforestation and degradation (Geist and Lambin, 2001; Turner II et al., 2001), (ii) trends towards restoration of forest cover and biodiversity through agroforestry or secondary succession in settled degraded areas (Nepstad et al., 1991; Perz and Skole, 2003; Kammesheidt, 2002) and (iii) a stable land use scenario in formal protected areas thinly populated by traditional communities. This study shows a fourth scenario viz., agriculture-forest mosaic landscapes where protective cover and high biodiversity at cultural landscape level has been maintained as also reported by Bray et al. (2004). Such stable landscapes bring out the significance of indigenous capacity to deal with the new problems and challenges. Yet, indigenous agricultural or forest management systems fail to people’s economic development aspirations and global demands of environmental conservation in Himalaya. Traditional societies do aspire to switch over from subsistence to market economy. Policy interventions need to be tailored for improving the local capacity for meeting this aspiration rather than to make them more and more dependent on external factors.

The study area is particularly exposed to forest degradation leading to habitat fragmentation and loss of biodiversity. This phenomenon is not desirable in the global change scenario. Thus a proper understanding of the associations between land use/cover change pattern and its influencing drivers is clearly essential in order to deal with the challenges of population increase, food security and protection of rich cultural heritage of traditional tribal communities of Northeast India.

Acknowledgements

We are grateful to the Ministry of Environment and Forests, Government of India, for financial support to carry out this study.

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