Differences in bird diversity between two swidden agricultural sites in mountainous terrain, Xishuangbanna, Yunnan, China

This study took a comparative look at the relationship between human-altered landscapes and bird diversity in two mountainous swidden (slash and burn) agricultural sites in Xishuangbanna, Yunnan, China. Over the course of 3 years (1998-2000) the authors used line-transect identification surveys in the two regions, Mengsong and Jinuo, where four different habitats were surveyed: 6-year fallow fields; traditional economic forests; monsoon evergreen broadleaf forests; and montane rain forests. Data were analyzed for species diversity, richness (family, genera, species), co-occurrence (family, genera, species), characterization of migratory status and feeding habits. Both of these study areas are inhabited by minority groups (Hani and Jinuo) that employ swidden agriculture as their main form of economic activity. The forest landscape in the Jinuo ethnic region is quickly transforming due to changing agricultural practices, and as a result bird diversity and richness are declining, while the Hani ethnic region (Mengsong), with a stable form of traditional swidden agriculture, is maintaining a high diversity and richness of birds. The greatest differences in bird diversity between the two sites occurred in the traditional economic forests and the 6-year fallow fields where the Hani region had a much greater richness and diversity. The two natural forest types (monsoon evergreen broadleaf forests and montane rain forests) were more similar in richness and diversity and also maintained the greatest richness and diversity of the four forest types analyzed. The transformation of healthy forests into degraded landscapes is one of the major impacts of human activity on the natural environment, which is posing a great threat to biodiversity. This study looks at the bird diversity of the two regions and tries to take into account how humans can extract economic benefits while preserving ecological benefits, such as a landscape that allows biodiversity to thrive.     

Recovery of soil macronutrients following shifting cultivation and ethnopedology of the Adi community in the Eastern Himalaya

Shifting cultivation involves a cycle of forest clearing, cultivation and a fallow phase. As the practice involves clearing forest, it is considered unsustainable and leads to soil fertility loss and erosion. While several variations of the practice exist, traditional communities undertake the practice systematically with relatively long fallow periods and are often knowledgeable about their landscape in terms of soil and its management. To better understand one such system, we quantified soil recovery following cultivation in terms of macronutrients and documented the traditional knowledge of the Adi community in a remote site in the Eastern Himalaya. We collected soil samples from three replicates, each from currently cultivated sites, uncut forest sites and successional sites 3, 12 and 25 yr following cultivation. Available nitrogen and phosphorus significantly increased, and there was an increasing trend in soil organic matter following cultivation. The Adi differentiated nine types of soil and preferred specific soil types for shifting and settled cultivation. We documented soil management and methods of soil fertility retention practised by the Adi. Their location of different crops in the field was based on the effect of the crop on soil fertility. Our research indicated that soil nutrient recovery was considerable following cultivation and that traditional shifting cultivators in the landscape were knowledgeable about their landscape in terms of soil diversity, undertaking practices to manage soil erosion and fertility. Future policies that will affect shifting cultivation in the region should acknowledge such systematic use of a landscape by traditional farming communities.     

Biocultural Diversity of Sarangani Province,Philippines: An Ethno-Ecological Analysis

This paper discussed effects of lowland-associated influences on upland ecology, food security and biocultural diversity in the Sarangani farming communities of the Philippines. In the uplands of Sarangani Province, the conservation of traditional rice varieties, the centrality of rice in tribal life, and the continued observance of planting rituals attest to its cultural significance and convey a common desire for cultural preservation and community solidarity. Economic and socio-political pressures had transformed tribal communities, although vestiges of traditional farming systems are still being practiced in remote sitios(villages). Changing land use patterns had also resulted in shrinking farm sizes and consequently in food insecurity in the Sarangani uplands. Extractive industries(i.e. logging, mining and charcoal making) and swidden farming were observed to cause widespread environmental degradation, while modern agriculture had undermined the capacity of indigenous peoples to survive because of their complete dependence on lands and resources. With the reality that cultural and biological diversities are inextricably linked, trans-disciplinary strategies coupling indigenous knowledge systems with scientific knowledge should, therefore, be instituted to save the Sarangani upland ecosystem, the indigenous peoples and their tribal resources.     

Dynamics of swidden agriculture in East Kalimantan

The Kenyah Dayak people began to migrate from the isolated area to the Mahakam basin in the early 1950's. As the Kenyah people migrate downstream, infiltration of monetary economy into the village increases, which leads to changes of life style, social structure such as work organization and mutual aid system in daily life, and so on. In the course of a series of such changes, sustainable swidden agriculture system is also changed to a less sustainable one. The Benuaq Dayak people, however, practice sustainable swidden (paddy) — rattan forestry system while they can earn much income. The Buginese way of land utilization, swidden (paddy) — pepper production system, is the least sustainable though the pepper production is the most profitable in the region. The land utilization by the transmigrated Javanese is not so sustainable at present, but there is a possibility of its getting more sustainable because of acquisition of the land ownership.     

Dynamics of soil chemical properties in shifting cultivation systems in the tropics: a meta‐analysis

The forest cultivation system (slash‐and‐burn or shifting cultivation) has contributed to the transformation of social systems since the early Neolithic period. Despite being considered by conservationists and public policymakers as a system of low productivity that generates environmental degradation and contributes to the maintenance of rural poverty, the shifting cultivation system (SCS) is being declared a practice that is highly ecologically and economically efficient. Such dichotomy of opinions is the consequence of the disparate results of studies assessing the effects of SCS on soil properties of rainforests throughout the last three decades. To circumvent this apparent inconsistency, we used a systematic quantitative review method (meta‐analysis), with the objective of integrating and synthesizing the data published in the literature to assess the overall effects of SCS on soil chemical properties. Four variables traditionally assessed in primary studies were chosen for the meta‐analyses: pH, cation exchange capacity (CEC), total carbon (Total C) and total nitrogen (Total N). Our results show that pH values increase under SCS conditions, while Total N and C content are significantly reduced under SCS. No significant impacts are observed on CEC. Our results on pH and CEC support the position from researchers who argue for the sustainability of SCS and highlight the importance of evaluating the soil system as a soil/vegetation complex. Also, our results indicate that soil chemical properties under SCS scenarios are better conserved and more readily recoverable, provided there is a rather longer fallow period than has been traditionally employed.     

Management of secondary tree species in agroforestry systems to improve production sustainability in Amazonian Ecuador

Three production systems (robusta coffee, cattle pastures and swidden agriculture), all associated with trees, have provided a strategy for regional development in the Ecuadorian Amazon. Feedback from more than 250 on-farm demonstrations, project evaluations and visitors have all contributed to strengthening the ability of the Ecuadorean Ministry of Agriculture's Forestry Directorate to provide colonists and indigenous groups with management guidelines for low-input sustainable agroforestry production. The existing market for 20 fastgrowing native tree species presents an opportunity for the diversification of farm income (currently dependent on robusta coffee) and for the development of a forest industrial base.The collective area of land owned and operated by these small holders constitutes a national resource and a Collective Forest Estate that can be individually managed. Commercial timber production in these extensive secondary forests can help alleviate conversion of primary forest without taking agricultural land out of production.     

Agroforestry in the South Pacific region — an overview

The developing countries of the Pacific Region consist of 27 countries and territories with a total nd area of 542 000 km² and over 5 million inhabitants. Though highly variable in physical characteristics and land-use pattern, these countries, in general, give a higher priority for production of export crops over other agricultural crops, so that they are net importers of food. Natural forests of the region are luxuriant and floristically rich, but the level of their commercial exploitation is low. Swidden cultivation is the mainstay of subsistence livelihood, but with the increase in population, the system is now causing severe environmental and land-use problems.The major agroforestry systems and practices in the region include various forms of combination of tree crops such as coffee, coconut and cacao with nitrogen fixing trees such as Casuarina, Gliricidia and Leucaena, and food crops (mostly tubers) such as cassava, taro, sweet potato and yams. Additionally, some improvements to swidden (shifting) cultivation are also being tried in several places, the most common being the u use of Casuarina oligodon before abandoning the swidden as in PNG highlands, and intercropping food crops in tree crop stands.Land tenure system in most of the countries is the traditional clan of extended family control over land. This can have either positive or negative influence on the adoption of agroforestry practices depending on the extent and duration of tenancy tenure enjoyed by the assignees of land.Several governments of the region are now promoting the agroforestry approach. In hilly areas with poor access, farmers are forced to produce most of their basic necessities locally. On the other hand, the lack of roads and communication facilities can pose a problem in marketing any surplus products they have.The immediate opportunity in agroforestry in the region lies in making better use of the unexplored potential of a large number of locally available trees and agricultural crops. Intercropping in tree crop stands and the taungya system seem to propromising m methods for the Pacific region.Researh Fellow, July–September, 1984     

Soil translocation by weeding on steep-slope swidden fields in northern Vietnam

This study investigated soil translocation associated with weeding on steeply sloped swidden fields attended by ethnic Da Bac Tay farmers in Hoa Binh Province in northern Vietnam. Annual soil loss rates of 4–6 Mg ha⁻¹ year⁻¹ were found on 20 m plots located on two separate hillslopes. Median soil flux rates were equivalent to 2.6–3.9 kg m⁻¹ pass⁻¹ for experiments conducted on slopes ranging from 0.54 to 0.84 m m⁻¹. The primary soil translocation process, the mechanical movement of soil via contact with a small hoe (ngheo), contributed approximately 60% of the weeding-related soil flux. Ravel, which is the rolling, bouncing, and sliding of soil clods downslope, was a secondary translocation process that accounted for almost 40% of the soil flux. Soil flux was most appropriately described with an exponential function that could predict the occurrence of ravel on steeper slopes. The observed soil fluxes were much smaller than those determined during weeding and hoeing at other tropical and subtropical sites, primarily because the tillage depth was very shallow (<1 cm) and weed density was low at the time of experimentation. The erosion rates associated with weeding were an order of magnitude lower than reported water erosion rates; therefore, the contribution to landscape change was believed to be small. Combined water and tillage erosion estimates indicated a possible unsustainable increase in soil loss on some steep-slope fields within the last few decades that has resulted from shorter fallow periods, longer periods of cultivation before fallowing, and greater weed pressure. Additional work is needed to verify these latter interpretations.     

Alternate cycle agroforestry

Agroforestry research and design has heavily favored intergrated production of annuals and perennials, that is production of tree crops on the same parcel of land and at the same time as production of food crop annuals. For areas having high population densities and intensive modes of agricultural production, integral agroforestry may be appropriate, but for areas of sparse population where extensive agriculture is practiced or marginal hill lands, alternate cycle agroforestry may prove more suitable. Alternate cycle agroforestry, in the form of modified forest swidden systems, is discussed and compared to integral agroforestry systems. Advantages and disadvantages of each system are discussed relative to their use on marginal hill and forest lands.The author wishes to thank N.T. Vergara, L.S. Hamilton, A.T. Rambo and K.F.Wiersum at the Environment and Policy Institute of the East-West Center for their comments.     

Composite farming systems in an era of change: Nagaland, Northeast India

Composite farming systems, first clearly identified by Rambo, are those in which radically different technologies are found together in a single farming complex. Data from diaries kept by groups of farming families in two Angami Naga villages in northeast India, Khonoma and smaller Tsiesema, detailing inputs into and outputs from wet-rice terraces and jhum (swidden) fields in the years 2000 and 2001, are presented and discussed to detail the workings of related but different composite systems. The 2000–2001 survey caught an important set of changes in midstream. Although returns to labour from the first-year jhums were much higher than those from the wet-rice terraces in 2000–2001, jhums were declining in significance as a growing non-farm economy joined the production of cool-climate vegetables and a spice crop for the Indian market as principal sources of livelihood. This story is told in the light of recent writing on the demise of swidden in the larger Southeast Asian region, and it is suggested that greater attention be paid to the composite systems, which are not uncommon in this region. This might help diversify what has perhaps been an oversimplified discussion.