Ole Mertz

Farmers' perceptions of climate change and agricultural adaptation strategies in rural Sahel.

Farmers in the Sahel have always been facing climatic variability at intra- and inter-annual and decadal time scales. While coping and adaptation strategies have traditionally included crop diversification, mobility, livelihood diversification, and migration, singling out climate as a direct driver of changes is not so simple. Using focus group interviews and a household survey, this study analyzes the perceptions of climate change and the strategies for coping and adaptation by sedentary farmers in the savanna zone of central Senegal. Households are aware of climate variability and identify wind and occasional excess rainfall as the most destructive climate factors. Households attribute poor livestock health, reduced crop yields and a range of other problems to climate factors, especially wind. However, when questions on land use and livelihood change are not asked directly in a climate context, households and groups assign economic, political, and social rather than climate factors as the main reasons for change. It is concluded that the communities studied have a high awareness of climate issues, but climatic narratives are likely to influence responses when questions mention climate. Change in land use and livelihood strategies is driven by adaptation to a range of factors of which climate appears not to be the most important. Implications for policy-making on agricultural and economic development will be to focus on providing flexible options rather than specific solutions to uncertain climate.

Adaptation to climate change in developing countries.

Adaptation to climate change is given increasing international attention as the confidence in climate change projections is getting higher. Developing countries have specific needs for adaptation due to high vulnerabilities, and they will in this way carry a great part of the global costs of climate change although the rising atmospheric greenhouse gas concentrations are mainly the responsibility of industrialized countries. This article provides a status of climate change adaptation in developing countries. An overview of observed and projected climate change is given, and recent literature on impacts, vulnerability, and adaptation are reviewed, including the emerging focus on mainstreaming of climate change and adaptation in development plans and programs. The article also serves as an introduction to the seven research articles of this special issue on climate change adaptation in developing countries. It is concluded that although many useful steps have been taken in the direction of ensuring adequate adaptation in developing countries, much work still remains to fully understand the drivers of past adaptation efforts, the need for future adaptation, and how to mainstream climate into general development policies.

The Demise of Swidden in Southeast Asia? Local Realities and Regional Ambiguities

Abstract Swidden farmers throughout Southeast Asia are rapidly abandoning traditional land use practices. While these changes have been quantified in numerous local areas, no reliable region-wide data have been produced. In this article we discuss three linked issues that account for at least some of this knowledge gap. First, swidden is a diverse, complex, and dynamic land use that data gatherers find difficult to see, define and measure, and therefore often relegate to a “residual category” of land use. Second, swidden is a smallholder category, and government authorities find it difficult to quantify what is happening in many dynamic and varied smallholdings. Third, national policies in all countries of Southeast Asia have tried to outlaw swidden farming and to encourage swiddeners to adopt permanent agriculture land use practices. Drawing on specific, local examples from throughout the region to illustrate these points, we argue that an accurate assessment of the scale and pace of changes in swidden farming on a regional level is critically important for identifying the processes that account for these shifts, as well as evaluating their consequences, locally and regionally.

Carbon outcomes of major land‐cover transitions in SE Asia: great uncertainties and REDD+ policy implications

Policy makers across the tropics propose that carbon finance could provide incentives for forest frontier communities to transition away from swidden agriculture (slash-and-burn or shifting cultivation) to other systems that potentially reduce emissions and/or increase carbon sequestration. However, there is little certainty regarding the carbon outcomes of many key land-use transitions at the center of current policy debates. Our meta-analysis of over 250 studies reporting above- and below-ground carbon estimates for different land-use types indicates great uncertainty in the net total ecosystem carbon changes that can be expected from many transitions, including the replacement of various types of swidden agriculture with oil palm, rubber, or some other types of agroforestry systems. These transitions are underway throughout Southeast Asia, and are at the heart of REDD+ debates. Exceptions of unambiguous carbon outcomes are the abandonment of any type of agriculture to allow forest regeneration (a certain positive carbon outcome) and expansion of agriculture into mature forest (a certain negative carbon outcome). With respect to swiddening, our meta-analysis supports a reassessment of policies that encourage land-cover conversion away from these [especially long-fallow] systems to other more cash-crop-oriented systems producing ambiguous carbon stock changes - including oil palm and rubber. In some instances, lengthening fallow periods of an existing swidden system may produce substantial carbon benefits, as would conversion from intensely cultivated lands to high-biomass plantations and some other types of agroforestry. More field studies are needed to provide better data of above- and below-ground carbon stocks before informed recommendations or policy decisions can be made regarding which land-use regimes optimize or increase carbon sequestration. As some transitions may negatively impact other ecosystem services, food security, and local livelihoods, the entire carbon and noncarbon benefit stream should also be taken into account before prescribing transitions with ambiguous carbon benefits.

Ecosystem services and biodiversity in developing countries

The concept of ecosystem services has become important for our understanding of the role of nature for maintaining human livelihoods. But is biodiversity essential to maintain ecosystem services? Many studies suggest that higher biodiversity allows a higher level of ecosystem services, but others argue that there is little hard evidence, especially from tropical environments, to document the necessity of high biodiversity for provision of most ecosystem services. Thus, effective valuation of biodiversity for ecosystem services and long-term studies and monitoring are needed to fully understand the complex biodiversity-ecosystem service interface. This introduction briefly reviews some of the main arguments in this debate and provides an overview of the other five special issue papers. Exploring biodiversity and ecosystem interactions in the context of the provision of ecosystem services, these papers address population and biodiversity coexistence, the importance of dung beetles in agricultural landscapes, the knowledge and use of palms by local communities, bioprospecting for drugs and how biodiversity conservation may have added benefits in terms of improved watershed functions and health.

Importance and seasonality of vegetable consumption and marketing in Burkina Faso

The use of vegetables in two rural communities in Burkina Faso is quantified through the use of food diaries kept by 13 households during one year. Interviews on preferences, field registration, and a market survey supplement the diaries. The use of wild species is concentrated onParkia biglobosa, Corchorus spp.,Adansonia digitata, andBombax costatum. At least five other wild species are mentioned as important but very rarely occur in the diet, indicating the usefulness of diaries compared to interviews.Capsicum frutescens, Abelmoschus esculentus, Allium cepa, andSolanum lycopersicon are the most commonly used cultivated species. Wild vegetables constitute 35% and 59% of the total vegetable consumption in the two communities. Most products are highly seasonal in supply and prices vary accordingly. Households compensate for the seasonality by drying products, but stocks are often insufficient and vegetable purchases needed. Many of the vegetable species studied should be integrated in agricultural research and extension programs.

Synthesis in land change science: methodological patterns, challenges, and guidelines

Global and regional economic and environmental changes are increasingly influencing local land-use, livelihoods, and ecosystems. At the same time, cumulative local land changes are driving global and regional changes in biodiversity and the environment. To understand the causes and consequences of these changes, land change science (LCS) draws on a wide array synthetic and meta-study techniques to generate global and regional knowledge from local case studies of land change. Here, we review the characteristics and applications of synthesis methods in LCS and assess the current state of synthetic research based on a meta-analysis of synthesis studies from 1995 to 2012. Publication of synthesis research is accelerating, with a clear trend toward increasingly sophisticated and quantitative methods, including meta-analysis. Detailed trends in synthesis objectives, methods, and land change phenomena and world regions most commonly studied are presented. Significant challenges to successful synthesis research in LCS are also identified, including issues of interpretability and comparability across case-studies and the limits of and biases in the geographic coverage of case studies. Nevertheless, synthesis methods based on local case studies will remain essential for generating systematic global and regional understanding of local land change for the foreseeable future, and multiple opportunities exist to accelerate and enhance the reliability of synthetic LCS research in the future. Demand for global and regional knowledge generation will continue to grow to support adaptation and mitigation policies consistent with both the local realities and regional and global environmental and economic contexts of land change.

Recognizing contemporary roles of swidden agriculture in transforming landscapes of southeast Asia.

Geography Department, AS2-04-21, 1 Arts Link, Kent Ridge. National University of Singapore117570, Singapore, emailgeoadz@nus.edu.sg†Program on Environment, East-West Center, 1601 East-West Road, Honolulu, HI 96848, U.S.A.‡Department of Biological Sciences, 14 Science Drive 4, National University of Singapore, Singapore, 117543

Climate change on three Polynesian outliers in the Solomon Islands: impacts, vulnerability and adaptation

Abstract Geografisk Tidsskrift—Danish Journal of Geography 109(1):1–13, 2009 Past and current impacts of climate change on three smalt islands, Ontong Java, Bellona and Tikopia, in the Solomon Islands are studied on the basis of a survey of production systems, household questionnaires and key informant and group interviews. Perceptions of the local population are compared to regional observations on climate variability and change. The adaptive measures taken in the past are identified. It is concluded that the capacity to cope with and adapt to climate variability and extreme weather events is well developed, and the social resilience of island communities appears to be high. It is further shown that the differences between islands are large with regard to the types of climate change observed, the exposure of the islands to the changes and the perceptions of the severity. The differences are due to location, bio-physical and terrain conditions and socio-economic factors, including the level of integration into a greater economic and demographic context, the importance of different productive activities and the social organization.

Fallow, labour and livelihood in shifting cultivation: implications for deforestation in northern Lao PDR

Abstract Shifting cultivation is often blamed for deforestation in tropical upland areas. Based on a case study of three villages in northern Lao PDR, this paper combines household surveys with a remote sensing based analysis of forest cover, covering the period 1989–1999, in order to analyse changes in shifting cultivation practices and livelihood strategies and the impact of these on deforestation. Due to population pressure and relocation of villages, easily accessed land is increasingly scarce and fallow periods have been shortened during the 1990s. A net annual deforestation of about 1% was found in the area during the study period. This deforestation rate reflects shorter fallow periods in secondary forests rather than encroachment on mature forests, which are not used for cultivation by the farmers in the three villages. Farmers rate scarce labour as a major constraint on shifting cultivation; nonetheless, a tendency towards lower labour input with shorter fallow periods is observed, contradicting conventional intensification theory. Livelihoods are diversifying through the establishment of plantations, cultivation of wet rice and adoption of animal husbandry, but given the socio-economic conditions in the area, shifting cultivation is likely to remain the most suitable farming system in the near future.