Shifting Cultivation

12 Key excerpts on "Shifting Cultivation"

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  Properties and Management of Soils in the Tropics

  • Pedro A. Sanchez(Author)
  • 2019(Publication Date)
  • Cambridge University Press

    (Publisher)

  The results are summarized in a book by Palm et al. (2005a). Along with research by soil scientists and ecologists working in Brazil, Costa Rica, Venezuela, Mexico, Fig. 16.2 A Shifting Cultivation field in North Carolina 1902 (top) looks similar to Shifting Cultivation in the Peruvian Amazon, 1972. Photos courtesy of Stanley Buol 434 SOILS AND SLASH-AND-BURN AGRICULTURE Côte d’Ivoire, Cameroon, Northeast India, Indonesia and Thailand, these efforts provide much of the information used in this chapter. 16.1 Shifting Cultivation and Slash-and-Burn Agriculture 1 16.1.1 Traditional Shifting Cultivation Throughout the humid tropics, traditional Shifting Cultivation practices are remarkably similar, consisting of forest clearing, a short cropping period and a long, second- ary-forest-fallow period of up to 15–20 years. Small areas of primary or tall secondary forests (normally 1–5 hectares) are cleared by axes and machetes during periods of least rain- fall, the biomass is left to dry during the short dry season and is burned shortly before the rains (Fig. 16.3). Without further removal of the debris remaining after the fire, crops such as upland rice, maize, beans, cassava, yams, bananas and plantains are planted in holes dug with a planting stick, or in mounds for root crops, as practiced in West Africa. Most traditional Shifting Cultivation systems consist of com- plex polycultures. They have a high diversity of crops, including trees and food crops in various forms of agrofor- estry. Intercropping is the norm, with several crop species and often various cultivars of the same species being grown together, resulting in high crop diversity (Okigbo and Green- land 1976, Thrupp et al. 1997). This diversity helps reduce the risk of pest and disease attacks, and provides a varied source of food, fruits and medicinal products. Crops are manually weeded and the regrowth from tree stumps is controlled with machetes.

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  Agricultural Engineering

  • (Author)
  • 2014(Publication Date)
  • Research World

    (Publisher)

  ____________________ WORLD TECHNOLOGIES ____________________ Chapter 10 Shifting Cultivation Shifting Cultivation is an agricultural system in which plots of land are cultivated temporarily, then abandoned. This system often involves clearing of a piece of land followed by several years of wood harvesting or farming, until the soil loses fertility. Once the land becomes inadequate for crop production, it is left to be reclaimed by natural vegetation, or sometimes converted to a different long-term cyclical farming practice. The ecological consequences are often deleterious, but can be partially mitigated if new forests are not invaded. Of these cultivators, many use a practice of slash-and-burn as one element of their farming cycle. Others employ land clearing without any burning, and some cultivators are purely migratory and do not use any cyclical method on a given plot. Sometimes no slashing at all is needed where regrowth is purely of grasses, an outcome not uncommon when soils are near exhaustion and need to lie fallow. The political ecology of Shifting Cultivation Shifting Cultivation is a form of agriculture in which the cultivated or cropped area is shifted regularly to allow soil properties to recover under conditions of natural successive stages of re-growth. In a Shifting Cultivation system, at any particular point in time a minority of 'fields' are in cultivation and a majority are in various stages of natural re-growth. Over time, fields are cultivated for a relatively short time, and allowed to recover, or are fallowed, for a relatively long time. Eventually a previously cultivated field will be cleared of the natural vegetation and planted in crops again. Fields in established and stable Shifting Cultivation systems are cultivated and fallowed cyclically.This type of farming is called jhumming in India.

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  Time Resources, Society and Ecology

  On the Capacity for Human Interaction in Space and Time

  • Tommy Carlstein(Author)
  • 2019(Publication Date)
  • Taylor & Francis

    (Publisher)

  Shifting Cultivation itself gives a hint of spatio-temporal structure and variability. As with food collectors, shifting cultivators must be mobile in space and time, but with different frequencies, durations and relative locations. Not only are individuals mobile but the settlement system itself undergoes spatial changes and shifts which reflect on society and habitat. Some of the previously outlined mechanisms are found also with shifting cultivators but in new combinations and with different magnitudes and significance. When stationary plants are cultivated, land (space-time) requirements also become more obvious perhaps and the cultural landscape more visible. In this context, carrying capacity and packing problems in a settlement space-time budget are more easily represented, although they are crucial in all systems and ecotechnologies.

  Conklin (1961) gives the following minimum definition for shifting or swidden cultivation: ‘any continuing agricultural system in which impermanent clearings are cropped for shorter periods in years than they are fallowed’. Pelzer (1945) has given a more inclusive definition by listing the following characteristics:

  • 1) rotation of fields rather than crops,
  • 2) clearing by means of fire,
  • 3) absence of draught animals and of manuring,
  • 4) use of human labour only,
  • 5) employment of dibble-stick or hoe, and
  • 6) shorter periods of soil occupancy altering with long fallow periods.

  Shifting agriculture has several names such as swidden, slash-andbum, field-forest rotation, and cut-and-bum agriculture. The term swidden was introduced by Izikowitz (1957:7) using an obsolete English word and it has since become widely used. It illustrates the most marked feature of this cultivation system: the use of fire as a tool for clearing and as a method of fertilization. The term ‘shifting’ emphasizes the space-time feature of relative impermanence of land occupation. It may sound objectionable to some to call this type of cultivation system ‘agriculture’ instead of horticulture or gardening, since ‘agri’-culture is generally associated with permanent fields under plough tillage. All the same, at the general level of analysis employed here, this distinction will be dropped.

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  Voices from the Forest

  Integrating Indigenous Knowledge into Sustainable Upland Farming

  • Malcolm Cairns(Author)
  • 2010(Publication Date)
  • Routledge

    (Publisher)

  The transfer of land ownership from local communities to the state also brought negative impacts to land management because the government was incapable of extending its management down to the lowest administrative levels in rural areas. Illegal selling of land by tribal cultivators to Viet (lowland) immigrants contributed to the scarcity of agricultural land and accelerated encroachment into forests. At the same time, agroindustry, and its demands for both markets and land, brought a major influence to the livelihoods of minority ethnic groups.

  An Economic, Social, and Environmental Assessment

  Shifting Cultivation is characterized by its minimal inputs, usually only human labor. No complicated tools, draft animals, irrigation, or fertilizers are used. Its low demands for investment make it suitable to resource-poor ethnic minorities. In terms of output, crop yields can only marginally meet the food needs of swidden populations and there is almost no surplus for marketing. Shifting Cultivation, therefore, is subsistence oriented and its practitioners often lack the resources to meet other basic needs.

  Shifting Cultivation not only generates low income, but also appears to be economically ineffective compared to alternative land uses. If, for instance, shifting cultivators converted their efforts to management and harvest of forest products, they would realize a far greater benefit. The growth rate of evergreen forest in the central highlands is very high and can reach volumes up to 300 m3 /ha/year. The potential value of forest products is two to three times that of the products from Shifting Cultivation.

  Because the land available for Shifting Cultivation is decreasing rapidly and crop yields within these degrading systems are themselves declining, traditional farming methods can no longer meet the food demands of the population, to say nothing of their other basic needs. Most farmers who rely heavily on Shifting Cultivation live far below the poverty line. According to criteria set by the Ministry of Labor, War Invalids, and Social Affairs, a “starving household” is defined as earning a per capita income equivalent to less than 8 kg of rice per month. A “poor household,” on the other hand, earns less than 15 kg of rice per month. In Shifting Cultivation communities, none of the households has sufficient food. Sixty percent of them fall into the “starving” category and the remaining 40% are regarded as “poor.”

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  Sustainable Rural Development through Agriculture

  • Gupta, Shobhana(Authors)
  • 2021(Publication Date)
  • Biotech

    (Publisher)

  More than 6 per cent area under tropical forests was converted to Shifting Cultivation between 1980 and 1990 across all tropical countries. On abandoned land, natural regeneration starts from 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. 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. 1.7 Impact of Shifting Cultivation Frequent shifting from one land to the other has affected the ecology of these regions. The area under natural forest has declined fragmentation of habitat, local disappearance of native species and invasion by exotic weeds and other plants are some of other ecological consequences of shifting agriculture. The Shifting Cultivation is generally practiced in the following sequence: Selecting a forest patch and clear fell the vegetation normally in December and January Burning of the vegetation and small, cut-trunks portion and roots are normally not removed. 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 cultivated site and shifting to other forest sites This ebook is exclusively for this university only. Cannot be resold/distributed. Returning to the former site, and once again practice Shifting Cultivation on it. Area having jhum cycle of 5 and 10 years is more vulnerable to weed invasion as compared to jhum cycle of 15 years.

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  Modernizing a Slave Economy

  The Economic Vision of the Confederate Nation

  • John Majewski(Author)
  • 2011(Publication Date)
  • The University of North Carolina Press

    (Publisher)

  Shifting Cultivation, in which a substantial portion of acreage rested in prolonged fallow. The basic routine of Shifting Cultivation began with the burning of forest growth to release nutrients into the soil. After five or six years, when the nutrients had been exhausted, the old field was abandoned to weeds, shrubs, and eventually trees. In the meantime, new fields would be burned and cropped. After fifteen to twenty years, the planter would return to the original “old field” and begin the process anew.

  Many antebellum observers considered Shifting Cultivation wasteful and inefficient, but it was a rational response to the soils, climate, and topography of the South. This chapter documents the environmental constraints that led planters and farmers to adopt Shifting Cultivation. Most southern soils were highly acidic and lacked key nutrients, which made it impossible for planters and farmers to use continuous cultivation. Southern farmers and planters also found it difficult to raise cattle and other livestock, which constituted a crucial link in recycling soil fertility in continuous-cultivation regimes. Debilitating livestock diseases flourished in the warm southern climate, while hay, clover, and other fodder crops wilted in the South’s heat and humidity. As was the case of many tropical and semitropical environments, the South’s environmental constraints proved exceedingly difficult to overcome.5 Even the introduction of railroads, the growth of nearby cities, and the introduction of new fertilizers did little to encourage more intensive cultivation practices in the antebellum decades. The fact that Shifting Cultivation flourished in some parts of the South well into the twentieth century indicates the degree to which the southern environment discouraged continuous cultivation.

  Shifting Cultivation often benefited individual farmers and planters, who profitably used land-intensive regimes to grow staple crops such as tobacco and cotton. For the South as a whole, however, Shifting Cultivation deterred development. The vast tracks of unimproved land resting in long-term fallow acted as a black hole that sapped the South’s economic vitality. Working in conjunction with slavery, Shifting Cultivation inhibited the growth of southern markets for manufactured goods and urban services. Cities such as Richmond, Norfolk, and Charleston, with sparsely settled hinterlands, languished in the shadows of Boston, Philadelphia, and New York. Traversing large stretches of land that generated little economic activity, railroads and other transportation corporations often generated fewer profits for investors. To make matters worse, Shifting Cultivation and slavery both dampened incentives to build institutions that could diffuse useful knowledge. The South’s widely dispersed free population made it difficult to establish schools and libraries, organize agricultural societies and mechanics’ institutes, and circulate periodicals and newspapers. In many measures of long-term economic development—urban growth, manufacturing output, and mercantile activity—Virginia and South Carolina ranked far behind most northeastern states.

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  The Economics of Land Use

  • Ian W. Hardie, Peter J. Parks(Authors)
  • 2017(Publication Date)
  • Routledge

    (Publisher)

  table 1 ). Grigg (1985, page 99) cites as much as one third of the world’s arable land in Shifting Cultivation as late as the 1970s. Many tropical soils are ancient and plant nutrients have been removed by leaching. Under intense agriculture, these soil types rapidly lose fertility (Fearnside, 1979; 1980; Sanchez et al, 1982). Eight months after establishing a cleared plot, symptoms of nitrogen and potassium deficiency begin to appear (Sanchez, 1979). Soil compaction reduces water penetration and encourages erosion (Gradwohl and Greenberg, 1988). The traditional response to these problems is to burn a small plot of forest, releasing nutrients and organics into the soil. The soil pH is raised, making nutrients more available (Hecht, 1985). But within a short period, the nutrients are depleted and soil acidity returns (Sanchez, 1979). Within a few growing seasons, productivity drops significantly (Herrera et al, 1981). At the same time, natural revegetation is rapid in the tropics. Indeed, the invasion of ‘weeds’ is often the motive for abandoning a field after a few years (Smith, 1978; Wilkins, 1991). This rapid revegetation has been documented in Brazil (Lynn Smith, 1972), and Peru (Sanchez and Nurena, 1972; Scott, 1974) in the `New World’, and in Sri Lanka (Joachim and Kandiah, 1948), Mindanao (Kellman, 1969), and New Guinea (Clarke, 1967) in the `Old World’ tropics. Native populations have used this approach for millennia (Reid, 1989). On the basis of this native experience, fallow agriculture is often recommended as an optimal strategy today (Gradwohl and Greenberg, 1988; Smith, 1982). The combination of poor soils and rapid revegetation makes fallow cultivation a useful strategy.

  Shifting Cultivation often is associated with time-bound, traditional practices, but changes in rotational practices throughout the developing world during the past two generations have suggested that shifting agriculturalists respond relatively quickly to economic and environmental changes. Grigg (1985, pages 98 – 99, 108, 142 – 147) notes the responsiveness of the length of fallow period to increasing population pressure around the Third World. Sometimes cultivators’ responses are based in an accurate, if intuitive, understanding of the social and natural relationships involved, particularly when the events remain within the sample space of their experiences. In other cases, involving more rapid and drastic environmental change, responses have not always been as fortuitous. In eastern Amazonia, colonization plans called for small holdings that permitted a family to use 8 ha fields for two years, followed by ten years of fallow (Smith, 1982). However, economic assessment suggested that corporate cattle ranching would be a more profitable use of the land (Hecht et al, 1988). Expected profits were greatest with grazing on unimproved soils. The result was extensive conversion of small, 75 ha farms into ranches with an average size of 620 ha (IBGE, 1987). The conversion resulted in deforestation, soil degradation, and erosion (Hecht et al, 1988).

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  A History of World Agriculture

  From the Neolithic Age to the Current Crisis

  • Marcel Mazoyer, Laurence Roudart(Authors)
  • 2006(Publication Date)
  • Monthly Review Press

    (Publisher)

  3Systems of Slash-and-Burn Agriculture in Forest Environments:

  Deforestation and the Formation of Post-Forest Agrarian Systems

  Humanity, disdainful of what was created without it, believes ... that it can develop [the planet] by destroying the slow accumulation of plant wealth that collaboration between the atmosphere and the earth had produced over thousands of centuries. Will the large ... tropical ... forest, this huge laboratory of climates, this humid and warm velvet belt of plants from which rhythmic spirals of atmospheric waves harmoniously soar, be transformed wisely, exploited with respect for humanity and nature, by taking into account its relationship with the soil and the atmosphere, or will humanity give in to the temptation to assault the earth, attack the tropical forest quickly and without thought? In the latter case, if one thinks about it, it is humanity itself which would be endangered, ... because the atmosphere would be unbalanced and instability would be introduced into climates around the whole world.

  —F. SHRADER , Atlas de géographie historique , 1896

  Slash-and-burn agriculture is practiced in diverse wooded environments: amid mature trees, in a copse, shrubby or bushy thickets, wooded savanna, etc. It is established on terrains previously cleared by grubbing, that is, cutting followed by burning but without removing the stumps. The parcels thus cleared are only cultivated for one, two, or three years, rarely more, after which they are abandoned to return to their wooded wild state for one or more decades, before being cleared and cultivated again. Systems of slash-and-burn agriculture, also called forest agrarian systems , are thus characterized by the practice of temporary cultivation alternating with long-term wooded idling, forming a rotation with a period varying from about ten to fifty years.

  The origin of these systems goes back to the Neolithic epoch. From that time on, they spread to most of the forests and other cultivable wooded environments of the planet, where they lasted for thousands of years. In each region of the world, this pioneer dynamic accompanied a strong demographic growth and was pursued as long as uncleared, accessible wooded terrain remained. When all these virgin reserves were used and the population density continued to increase, the frequency and intensity of clearings increased, thus beginning a dynamic of deforestation of lands cultivated by slash-and-burn techniques. Ultimately, this resulted in the impossibility of pursuing this mode of cultivation. Deforestation generally resulted in deterioration of fertility, development of a more or less serious erosion problem, depending on the biotope, and worsening of the climate, even up to the point of desertification.

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  Rethinking African Agriculture

  How Non-Agrarian Factors Shape Peasant Livelihoods

  • Goran Hyden, Kazuhiko Sugimura, Tadasu Tsuruta(Authors)
  • 2020(Publication Date)
  • Routledge

    (Publisher)

  Subsistence is the core principle driving agricultural production in Africa’s Natural Societies. It takes place in an environment that is little changed over time and, above all, is adjusted to what circumstances permit. Income from land, however, has become increasingly insufficient as local peasant communities have become integrated into the market economy. The response to these changes has been a diversification of livelihood sources rather than an intensification of land use in search of higher productivity. Yet another feature of these Natural Society communities is the tendency to share of whatever household members may have among themselves, so nobody goes hungry. We shall cover each of these points in greater detail below.

  Shifting Cultivation embedded in a natural environment

  Shifting Cultivation, variously referred to as “swidden” or “slash-and-burn” agriculture, also “forest (bush) fallow”, has been a dominant form of farming in sub-Saharan Africa for a long time. This is still practiced widely, particularly in humid forest zones with an annual rainfall of more than 1,500 mm. Mixed cropping, also known as intercropping, in which more than one crop is grown simultaneously on the same piece of land is also a widespread practice across the subcontinent. The combination of forest fallow and mixed cropping (or just “fallow-mixed cropping”) is a farming system embedded in the forestry ecosystem, in the sense of being dependent on the natural cycle of vegetation regrowth and the replenishment of soil fertility. This system stands in contrast to the major farming systems of Agrarian Societies, which are characterized by humanity’s determination to control nature.

  The fallow-mixed cropping system has generally been considered a rudimentary technology characterized by low levels of land productivity. In addition to being viewed as incompatible with commercial production, it has been criticized for leading to extensive deforestation. In a counterargument, Paul Richards (1985) argued that both Shifting Cultivation and mixed cropping are rational farming systems with their own advantages, bolstered by villagers’ intimate knowledge of the ecosystem and their constant innovation. African indigenous farming systems, therefore, have an untapped potential for development. Mixed cropping has its own merits by deconcentrating risks of disease and pest, securing foods throughout the season, providing a variety of dietary nutrients, and levelling uneven labor peaks, as harvest seasons for each crop tend to differ.

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  The Forest Farms of Kandy

  and Other Gardens of Complete Design

  • D.J. McConnell, K.A.E. Dharmapala, S.R. Attanayake(Authors)
  • 2017(Publication Date)
  • Routledge

    (Publisher)

  Shifters ... and Forest Gardens as Alternative

  By selection it's possible to prove or disprove almost anything about the shifters but five propositions seem to hold their ground: Until undone by circumstance —population, commercial temptation, scowls of displeasure from their Prince - they managed to achieve a 'balanced exploitation' of their environment, to use Hans Ruthenberg's phrase. Through the millennia they modified it enormously, but what other macro-fauna hasn't? As resource managers they've been more successful than most - H. sapiens' survival proves it. On almost every count they've done less damage to the natural world in 20 000 years or so than modern agriculture has inflicted in the last 200. In economics' vision of the future, their time is running out. But there is still much to be learnedfrom the shifters.

  Swiddening (old English) or shifting or slash-and-burn agriculture is one of the two fountains of agriculture generally and forest gardens in particular. (The first in time was manipulation of the Great Forest - Genesis.) In both the tropics and temperate worlds, as technology, it was present at the birth of conventional field crop farming (Origins, the Flannery models). In the contemporary world it is considered wasteful, especially of tropical forests, obsolete and urgently in need of advancement to more productive systems. The thrust of this has been to move the shifters on to proper field crop farming; but it is suggested here a better alternative would be to pick up the ancient tree crops stream which was present in tropical shifting agriculture and develop that instead of the ground crops stream (Evolution, below).

  7.1 Shifters and the Origins

  Swiddening is now confined largely to the tropics but as recently as 1920 it was still common in North Europe and existed in remote places in Finland into the 1970s. It referred to the cutting/burning of some forest patch to grow a few years of food crops until fertility was depleted, then the swidden was abandoned for a longer period for tree regrowth and fertility restoration. In Europe its origins lie far back (Parain 1942). As agriculture (wheat and barley) filtered up the river valleys from its Near East hearth it required removal of the great oak forests. One of its earliest archeological records here, c 7 000 BP, is as layers of oak charcoal and various pollens, the fingerprints of shifters. There is similar archeobotanical evidence that as agriculture moved further north to colder and less fertile sandy soils wheat and barley were replaced by rye and oats and the swidden system became more deliberative, eventually stabilizing before the 17th century as a cycle of 4-6 years of crops followed by 20-30 years of restorative birch and pine forest. From then on in Europe but less so the tropics, these two land use activities became separated - the forests managed as forests and the swiddens as permanent farms. With the trees removed as fertility source this was replaced by a grass ley phase and livestock.

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  Agroforestry

  Systems And Prospects

  • C.B.Pandey O.P.Chaturvedi, C.B.Pandey & O.P.Chaturvedi(Authors)
  • 2021(Publication Date)
  • NEW INDIA PUBLISHING AGENCY (NIPA)

    (Publisher)

  Jhuming is also practiced in southern (Andhra Pradesh, Tamil Nadu, Kerela), Eastern (Bihar, Orissa) and Central (Madhya Pradesh) part of India (Table 1). Shifting Cultivation is a time-tested system of agricultural practice, most often evolved indigenously and strongly based on traditional knowledge. It is considered to be an appropriate and sustainable land use practice in diverse socio-economic setup, where the dependant human population was within the carrying capacity of a 10-15 year jhum cycle. Today the Shifting Cultivation became unsustainable due to reduced jhum cycle of 3-6 years owing to the increase in population that led to increase in food demand. This has caused decrease in productivity necessitated in bringing more virgin forest area under jhuming. Jhuming is a tribe specific cultivation practice and varies widely in different parts of North East India. The system involves cultivation of crops even on steep slopes. Land is cleared by cutting of forests, bushes, etc. up to the stump level in December – January, leaving the cut materials for drying and finally burning to make the land ready for sowing of seeds of different crops before the onset of rains. The cultivation is confined to a village boundary and often after two or three years the cultivated area is abandoned and a new site is selected to repeat the process. The hutments of the village remain at the same place. Earlier whole village of some communities used to shift to the new site. After 2 – 3 years of cropping when the land losses its fertility farmers shift to another piece of virgin forest land for cultivation. After 3 – 15 years, when the vegetation in deserted land regenerates during the fallow period, the farmer again come back for farming on the same piece of land. With the rising population, the jhum cycle in most areas which used to be 10 – 15 years earlier has now reduced to 3-6 years only.

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  Recent Advances in Remote Sensing and Geoinformation Processing for Land Degradation Assessment

  • Achim Roeder, Joachim Hill, Achim Roeder, Joachim Hill(Authors)
  • 2009(Publication Date)
  • CRC Press

    (Publisher)

  Slash-and-burn cultivation with short fallow periods is associated with deterioration of soil nutrient and physical conditions, and increase of weeds, pests and diseases, which results in lowered crop yield, less labor productivity as well as degradation of forest resources including non-timber forest products (NTFP) (Fjisaka 1991, Roder 2001). It is also suggested that natural vegetative succession back to forest is unlikely even with long fallow after prolonged slash-and-burn land use (Gomets-Pompa et al. 1972). Hence, the land use may be no longer sustainable, and the situation is often referred to as the vicious spiral of shortening of fallow periods, decreasing crop yield and increasing cropping labor (mainly weeding), increasing food insecurity and poverty, and expansion of slash-and-burn land use (e.g., Pravongvienkham 2004). It is obvious that forest resources are linked inevitably with the slash-and-burn land use and that crop productivity. It is strongly required to develop alternative cropping and ecosystem management scenarios for food, resource and environmental security. A number of assistance programs by international agencies (e.g. SIDA) have been implemented to protect forests and to reduce poverty mostly through socio-economic, forestry and agricultural activities. However, quantitative assessment of land use, especially at a geo-spatial basis, is still limited. Accurate statistics on land use are hardly available. On the other hand, regional land-use change is strongly linked not only with crop productivity but also with the CO 2 flux by biomass burning or biomass stock capacity as found in such as Brazil (Cochrane et al. 1999, Czimczik et al. 2005). From the viewpoint of carbon cycle science, quantitative estimation of carbon exchange between the atmosphere and ecosystems as affected by the land-use change is also required since the site specific data in the region are still very limited (IPCC 2003).

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