Coppice swidden fallows in tropical deciduous forest: Biological,technological, and sociocultural determinants of secondary forest successions

Secondary succession in tropical deciduous forest is often characterized by vegetative reproduction, or coppicing. Coppicing is also observed in forest sites that are disturbed by farming activity. This observation raises questions about the role of established management practices in determining the succession of vegetation on farmsites once they are abandoned to fallow. To what extent is the coppicing succession the result of specific aspects of swidden farming technology and management? And what variations in coppice successions occur in swidden sites following deviations from the standard farming practice? In research on swidden farming among the Susu of Sierra Leone, I examined the successional pathway in an age series of forest fallow sites. I show that the standard pattern of minimal cultivation favors the coppicing of felled trees in the subsequent fallow periods. By contrast, deviation from this pattern results in stump deaths and favors the invasion of fallow sites by grasses and vegetatively reproducing pioneer trees from the savanna. Variations in the environmental outcome of disturbance to plant communities, then, are the result of interactions between processes of tropical tree reproduction and the agricultural practices of local farmers.     

Persistence of Swidden Cultivation in the Face of Globalization: A Case Study from Communities in Calakmul, Mexico

Over the last decades, political, economic and environmental pressures have encouraged changes from swidden to more intensive agricultural practices, resulting in the hypothesis that swidden cultivation systems are disappearing. In Calakmul, southeastern Mexico, communities decreased the area under milpa, the traditional maize swidden system, but a collapse did not occur. To document and explain the persistence of swidden we employ a variety of data: (1) 59 standardized household surveys from 2003 and 2010 in five villages, (2) in-depth interviews in one village, and (3) coupled human–environmental timelines in this same village. Droughts, hurricanes, and remittances were important drivers of decreases in milpa cultivation. Market crop profitability and conservation programs were also reported to affect the area under milpa. Off-farm employment and governmental transfers have tended to stabilize household economies and decrease dependency on agricultural production, but have also allowed households to maintain their milpas for subsistence and cultural reproduction. Findings in Calakmul point to the need to consider swidden as an evolving and active response to changing policy, economic, and environmental conditions.     

Agricultural intensification in a Philippine frontier community: Impact on labor efficiency and farm diversity

There continues to be much debate in anthropology concerning the mechanism by which agricultural intensification takes place and its impact on labor efficiency, farm diversity, and quality of diet. A major reason for this lack of consensus is the paucity of data from case studies that focus on specific agricultural systems at the point of transition from extensive to intensive methods of cultivation. Research in a frontier community in the Philippines, where farmers are making the shift from swidden cultivation to small-scale irrigated rice production, indicates that intensification does not necessarily result in lower efficiency or a decline in dietary standards. Rather, farmers faced with growing population pressure and an unproductive short fallow swidden system have been motivated to adopt irrigation because it increases the efficiency of their labor while maintaining a reliable and diverse farming system.     

Strategies for improving water use efficiency of livestock production in rain-fed systems

Livestock production is a major consumer of fresh water, and the influence of livestock production on global fresh water resources is increasing because of the growing demand for livestock products. Increasing water use efficiency of livestock production, therefore, can contribute to the overall water use efficiency of agriculture. Previous studies have reported significant variation in livestock water productivity (LWP) within and among farming systems. Underlying causes of this variation in LWP require further investigation. The objective of this paper was to identify the factors that explain the variation in LWP within and among farming systems in Ethiopia. We quantified LWP for various farms in mixed-crop livestock systems and explored the effect of household demographic characteristics and farm assets on LWP using ANOVA and multilevel mixed-effect linear regression. We focused on water used to cultivate feeds on privately owned agricultural lands. There was a difference in LWP among farming systems and wealth categories. Better-off households followed by medium households had the highest LWP, whereas poor households had the lowest LWP. The variation in LWP among wealth categories could be explained by the differences in the ownership of livestock and availability of family labor. Regression results showed that the age of the household head, the size of the livestock holding and availability of family labor affected LWP positively. The results suggest that water use efficiency could be improved by alleviating resource constraints such as access to farm labor and livestock assets, oxen in particular.     

Variation in Swidden practices in four central Brazilian Indian societies

It has been suggested that indigenous tropical forest agriculture, in contrast with other agricultural systems, is characterized by a high degree of polyculture, and, being similar in diversity to the forest itself, has little disturbing effect on the generalized ecosystem that surrounds native gardens. Our comparative study of four Central Brazilian Indian groups shows, however, that while each of these groups practices polyculture to some extent, the crop mix found in their swidden plots is highly patterned, and includes single crop stands at certain stages of garden life. Different crops are planted in the same swidden plot from year to year, in accordance with variation in soil fertility within the swidden cycle. None of the swiddens we observed compares in complexity to the surrounding forest. We suggest that polyculture, rather than being regarded as the distinguishing characteristic of swidden cultivation, should be considered as a varying dimension—along with other variables such as use of wild plants, soil fertility and exhaustion, tillage practices, the introduction of novel crops, and production for the market—within the overall subsistence strategy of a group.     

Farmers’ Perspectives on Vital Soil-related Ecosystem Services in Intensive Swidden Farming Systems in the Peruvian Amazon

A growing dilemma is how to conserve Amazonian forest while allowing local people to secure their livelihoods. Small-scale swidden farming in Amazonia is entirely dependent on the continued provision of ecosystem services (ES) that generate the conditions for agriculture. This study identified soil-related ES needed for, and enhanced by, productive swidden systems from the farmer’s perspective. Workshops in six farming communities in northeastern Peru discussed various land uses, swidden systems that continue to be productive, and swidden systems on degraded land. The participating farmers noted changes in their production systems and described the ES (or lack thereof) in terms of soil quality, crop production quantity and quality, burning practices, forest regeneration, and farming skill. The central elements described in farmers’ own strategies for managing soil-related ES were fallow management for biomass production and crop diversity, factors identified as central to future ES management work in established agricultural areas in Amazonia.     

Shifting Cultivation and Fire Policy: Insights from the Brazilian Amazon

Fires in humid tropical forests are increasingly frequent due to severe dry seasons, forest degradation and agricultural expansion. One agent implicated in current discourse surrounding tropical forest fires is the small-scale farming peasantry who rely on fire in swidden (shifting cultivation, slash-and-burn) agriculture. The environmental degradation associated with fire has led to government responses at multiple scales (international, national, state, regional) via policies aimed mainly at managing ignition sources. However, continued increase in forest fires suggests that these policies may be having limited impact and a fresh evaluation of current policy approaches to fire management is needed. We review fire policy measures with insights of caboclo farming practices and perspectives from Eastern Amazonia and examine the congruence between policy and practice. We demonstrate a significant disparity between policy requirements such as firebreaks and actual fire management practices, in which measures rarely meet requirements outlined in legislation. We explore the origins and the impacts of these disparities, focussing on smallholder farm-level management measures and local capacity. Incomplete knowledge coupled with marginal awareness of legal requirements served to propagate widespread erroneous beliefs in what these are. This analysis at multiple scales (international, national, state, regional) will contribute to developing greater congruence between fire policies and smallholder farming practices.     

Environmental Consequences of the Demise in Swidden Cultivation in Montane Mainland Southeast Asia: Hydrology and Geomorphology

The hydrological and geomorphological impacts of traditional swidden cultivation in Montane Mainland Southeast Asia are virtually inconsequential, whereas the impacts associated with intensified replacement agricultural systems are often much more substantial. Negative perceptions toward swiddening in general by governments in the region beginning half a decade ago have largely been based on cases of forest conversion and land degradation associated with (a) intensified swidden systems, characterized by shortened fallow and extended cropping periods and/or (b) the widespread cultivation of opium for cash after the Second World War. Neither of these practices should be viewed as traditional, subsistence-based swiddening. Other types of intensive agriculture systems are now replacing swiddening throughout the region, including semi-permanent and permanent cash cropping, monoculture plantations, and greenhouse complexes. The negative impacts associated with these systems include changes in streamflow response, increased surface erosion, a higher probability of landslides, and the declination in stream water quality. Unlike the case for traditional swiddening, these impacts result because of several factors: (1) large portions of upland catchments are cultivated simultaneously; (2) accelerated hydraulic and tillage erosion occurs on plots that are cultivated repetitively with limited or no fallowing to allow recovery of key soil properties, including infiltration; (3) concentrated overland flow and erosion sources are often directly connected with the stream network; (4) root strength is reduced on permanently converted hillslopes; (5) surface and ground water extraction is frequently used for irrigation; and (6) and pesticides and herbicides are used. Furthermore, the commercial success of these systems relies on the existence of dense networks of roads, which are linear landscape features renowned for disrupting hydrological and geomorphological systems. A new conservation focus is needed to reduce the impacts of these intensified upland agricultural practices.     

Characterizing Rural Household Differentiation from the Perspective of Farmland Transfer in Eastern China Using an Agent Based Model

Over the past several decades in China there has been a large amount of rural labor flow to non-farm industries as well as an increase in farmland transfers that have resulted in significant differentiation of farmer households and changes in agricultural land use pattern. For this study we developed an agent-based model to explore this process and the resulting concentration of agricultural production by characterizing the households’ decision-making behavior with respect to farmland transfer in Jinze Town, located in the developed eastern region in China. The model simulated the household agents’ farmland transfer behavior, reproduced the evolution and differentiation of household agents, and explored changes of farm area distribution across household types from 2005 to 2020. Small households, the dominant demographic as well the main agricultural producers at the beginning of the simulation, decreased radically and cultivated the smallest area of farmland by the end. In contrast, large-scale farming households increased rapidly and became the main agricultural producers. The majority of households entirely exited farming in favor of urban employment. We examine how farm households’ attributes influence their farmland transfer behavior and subsequent livelihood choices in the specific socioeconomic and political context in the research region. We conclude with policy suggestions for the provision of a favorable environment for both large-scale farm households and those who leave farming altogether. Our findings can provide references for land use policies in other transitional rural areas.     

Swidden, Sawah, and In-Between: Agricultural Transformation in Borneo

The change from swidden to sawah cultivation in Tara'n Dayak villages in West Kalimantan, Indonesia, is presented as a long-term, complex incremental process in which distinct, unstable, and often confusing production technologies figure as transitional forms. The transitional phases are discussed in terms of their efficiency and sustainability. It is argued that the failure to perceive and understand long-term processes of agricultural change may result in both misinterpretation of technological patterns and environmental variables, as well as of rules of labor and resource sharing.     

Agricultural diversification as an important strategy for achieving food security in Africa

Farmers in Africa have long adapted to climatic and other risks by diversifying their farming activities. Using a multi‐scale approach, we explore the relationship between farming diversity and food security and the diversification potential of African agriculture and its limits on the household and continental scale. On the household scale, we use agricultural surveys from more than 28,000 households located in 18 African countries. In a next step, we use the relationship between rainfall, rainfall variability, and farming diversity to determine the available diversification options for farmers on the continental scale. On the household scale, we show that households with greater farming diversity are more successful in meeting their consumption needs, but only up to a certain level of diversity per ha cropland and more often if food can be purchased from off‐farm income or income from farm sales. More diverse farming systems can contribute to household food security; however, the relationship is influenced by other factors, for example, the market orientation of a household, livestock ownership, nonagricultural employment opportunities, and available land resources. On the continental scale, the greatest opportunities for diversification of food crops, cash crops, and livestock are located in areas with 500–1,000 mm annual rainfall and 17%–22% rainfall variability. Forty‐three percent of the African cropland lacks these opportunities at present which may hamper the ability of agricultural systems to respond to climate change. While sustainable intensification practices that increase yields have received most attention to date, our study suggests that a shift in the research and policy paradigm toward agricultural diversification options may be necessary.     

高黎贡山地区民族植物学的初步研究Ⅱ.独龙族

采用民族植物学和人类生态学的方法,初步研究了云南高黎贡山北部独龙江流域内独龙族的农业生态系统和采集利用植物的传统知识。处于近乎封闭的自然与社会环境中,独龙族与植物及植物环境的关系十分密切。独龙族的农业生态系统是典型的山地轮歇农业生态系统,系统中存在不少有价值的传统品种和地方品种,并以种植桤木(Alnus nepalensis)来促进轮歇地的休闲管理为特色,对保护当地的森林、生态系统和生物多样性起到了积极的作用。独龙族人人参与野生食用植物的采集活动,它是独龙族社会中仅次于农业生产而位居第二的重要经济活动,共采集100余种野生食用植物,其中有很大一部分是能代替粮食的产淀粉类植物。独龙族采集利用100多种药用植物,云黄连(Coptis teeta)和贝母(Fritillaria cirrhosa)等草药储量丰富,是独龙族用于同外界进行物资交换的主要物品。在其它植物资源的利用方面,独龙族也积累了丰富的传统知识,包括对纤维植物、染料植物等的认识和利用。桤木和董棕(Caryota urens)两个树种是体现独龙族传统植物学和生态学知识的代表种类。独龙族对植物的传统知识,有必要进行深入研究。     

Aquatic Ecosystem Impacts of Land Sharing Versus Sparing: Nutrient Loading to Southeast Asian Rivers

As world food demand continues to increase, two broad strategies for agricultural production have been widely discussed: land sparing and land sharing. Reflecting tradeoffs between the extent and intensity of agricultural use, land sparing maximizes the ratio of conserved to agricultural land, whereas land sharing allows more extensive, nature-friendly transformation of the agroecological matrix. Freshwater ecosystems are rarely considered in weighing these strategies, despite being strongly affected by land-use change. Here we analyze how shifting from extensive to intensive agricultural practices is altering dry season riverine nutrient availability and algal growth in upland Southeast Asia, which is experiencing rapid conversion from swidden—or shifting—cultivation to fertilized row crops. In situ algal growth assays and nutrient concentration data from eleven catchments representing a spectrum of land use and population densities show that intensive agriculture is associated with significantly elevated nitrate concentrations but no shift in phosphorus. As a result, nitrogen to phosphorus ratios increases dramatically, shifting algal growth toward colimitation by nitrogen and phosphorus. Geochemical analysis of suspended solids suggested comparable geological inputs across basins, but dissolved rare earth elements reveal that inorganic fertilizers are changing water chemistry in parallel with land use. Taken together, our analyses suggest that the transition from low-input land-sharing management (swidden) to high-input land-sparing practices (intensive row-crop agriculture) underway in Southeast Asia has profound consequences for river ecosystems. Such nutrient loading can affect river productivity and food webs, suggesting that land-use conservation strategies for Southeast Asia need to account for impacts on freshwater ecosystems.     

Socioeconomic determinants of cultivation of non-wood forest products in southern Nigeria

Cultivation of non-wood forest products (NWFP), although a veritable means of ecosystem and biodiversity conservation and improved natural resource management, has not been sustained in southern Nigeria (Nigeria’s major forest region) notwithstanding the unprecedented rate of depletion of the resource in the wild. For example, efforts in the past to support cultivation of NWFP in southern Nigeria under a USAID funded Cross River State forestry project, especially through nursery establishment for some rural communities, was not sustained as the initiative was abandoned by the participants. Hence to promote cultivation of NWFP, this study ascertained socioeconomic factors that influence cultivation of NWFPs. Multi stage sampling technique was used in selection of respondents (households) from two States: Cross River and Enugu States of southern Nigeria. A sample size of 400 households was used for the study. Probit and multinomial logistic regressions were used in estimating NWFP cultivation. The findings show that cultivation of NWFP was positively determined by gender, farming occupation (especially of women farmers) distance to forests where NWFP was collected, proportion of household food from NWFP, and medium wealth category. Age had a negative effect on cultivation until the age of 46 after which the effect became positive. In addition, household size, gender and farming occupation of household heads positively influenced cultivation of NWFP in plantations as against home gardens while gender and farming occupation had positive effect on cultivation of some stands of NWFP as against home gardens. Incorporating the findings of this study in future intervention project for NWFP cultivation will help sustain the initiative.     

Changing Realities—Perspectives on Balinese Rice Cultivation

This paper discusses issues of agrarian change in south-central Bali. The proximity to urban areas, especially the tourist centers along the southern coast, provides many off-farm employment opportunities for small-scale farming households. Although rice farming continues, for many households it has become a side business. The flexible nature of rice farming in terms of labor input and available casual off-farm work allows farming households to allocate their available labor to a variety of on-farm and off-farm income generating activities. The subak which unites farmers in the irrigation and cultivation of the rice crop plays an important role in supporting this flexibility. Still, the future of rice farming and the organization behind it looks rather dim with a younger generation unwilling to work in the “mud” and little appreciation of the many benefits the subak provides not only to the farming but to the wider community.     

耕种措施对农田生态系统AM真菌群落结构的影响

丛枝菌根（arbuscular mycorrhiza,AM）真菌群落在农田生态系统过程中扮演着重要角色,其在改善土壤结构、增强土壤肥力、提高作物产量和抗病抗逆性等方面发挥着重要的功能。但由于农田生态系统是一种受人为干扰非常强烈的半自然生态系统,特别是施肥、种植模式、喷施农药等耕种措施均对AM真菌侵染强度、生物量、孢子密度和群落多样性产生一定的影响。本文综述了近十几年来耕种措施对AM真菌群落结构的影响,以期通过利用合理的耕作与管理措施,提高AM真菌对农田生态系统生产力的生态效应,建立符合生态、经济和社会三重效益的可持续发展型现代化农业。     

The Rationality of Shifting Cultivation Systems: Labor Productivity Revisited

This paper reviews the theoretical and empirical literature on labor productivity in shifting cultivation systems, and relationships between labor productivity and production parameters are analyzed in two case studies of Iban communities in Sarawak, Malaysia, during two farming seasons. In addition, the labor productivity in shifting cultivation compared to off-farm wage labor opportunities is explored. Establishing firm relationships between labor productivity and production parameters, such as fallow length, fertilizer use, and herbicide use was not possible. We are thus unable to verify or reject the thesis that more labor is required for managing fields after short fallow compared to long fallow periods. We do demonstrate that shifting cultivation of hill rice can compete economically with common off-farm employment opportunities, and conclude that farmers’ decisions to maintain their practices is based as much on economic rationales as on tradition.     

An Assessment of Trends in the Extent of Swidden in Southeast Asia

Swidden systems consisting of temporarily cultivated land and associated fallows often do not appear on land use maps or in statistical records. This is partly due to the fact that swidden is a diverse and dynamic land use system that is difficult to map and partly because of the practice of grouping land covers associated with swidden systems into land use or land cover categories that are not self-evidently linked to swiddening. Additionally, in many parts of Southeast Asia swidden systems have changed or are in the process of changing into other land use systems. This paper assesses the extent of swidden on the basis of regional and national sources for nine countries, and determines the pattern of changes of swidden on the basis of 151 cases culled from 67 articles. Findings include (1) a majority of the cases document swidden being replaced by other forms of agriculture or by other livelihood systems; (2) in cases where swiddening is still practiced, fallow lengths are usually, but not always, shorter; and (3) shortened fallow length does not necessarily indicate a trend away from swidden since it is observed that short fallow swidden is sometimes maintained along with other more intensive farming practices and not completely abandoned. The paper concludes that there is a surprising lack of conclusive data on the extent of swidden in Southeast Asia. In order to remedy this, methods are reviewed that may lead to more precise future assessments.     

Environmental Consequences of the Demise in Swidden Cultivation in Southeast Asia: Carbon Storage and Soil Quality

The effects of swidden cultivation on carbon storage and soil quality are outlined and compared to the effects of the intensified production systems that swidden systems of Southeast Asia transform into. Time-averaged aboveground carbon stocks decline by about 90% if the long fallow periods of traditional swidden cultivation are reduced to 4 years and by about 60% if swidden cultivation is converted to oil palm plantations. Stocks of soil organic carbon (SOC) in tree plantations are 0–40% lower than stocks in swidden cultivation, with the largest losses found in mechanically established oil palm plantations. Impacts of tree plantations on soil quality are to a large extent determined by management. Conversion of swiddening to continuous annual cropping systems brings about substantial losses of time-averaged aboveground carbon stocks, reductions of SOC stocks and generally leads to declining soil quality. Knowledge of carbon storage in belowground biomass of tree based systems of the tropics is sparse but failure to include this pool in carbon inventories may significantly underestimate the total biomass of the systems. Moreover, studies that consider the ecological reasons behind farmers’ land use decisions as well as spatial variability in biogeophysical and edaphological parameters are needed to evaluate the effects of the ongoing land use transitions in Southeast Asia.     

The Ecology of Wealth-in-People: Agriculture, Settlement, and Society on the Perpetual Frontier

For the Susu of northwestern Sierra Leone, rural settlement dynamics reflect a frontier culture history and the perpetuation of frontier sociopolitical arrangements in village life. Under frontier conditions people are wealth. The competition among male elders for wealth-in-people is a major determinant of village movements and the organization and deployment of agricultural labor. In this article, I explore the implications of frontier social arrangements, as illustrated in the careers and lives of individual elder men, for the ecology of swidden agriculture. One significant result is a competitive scramble for labor, which both hinders crop production and leads to problems of intensification and resource degradation. I conclude that local problems of resource management are the result of individual efforts to achieve and maintain social position in the context of established systems of hierarchy.