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This paper reviews 91 recent empirical and theoretical studies that analyzed land-use change at the farm-household level. The review builds on a conceptual framework of land-use change drivers and conducts a meta-analysis. Results show that the conversion of forests into cultivated land or grassland, mainly used for agriculture or ranching, are most frequently analyzed. Only a small number of studies consider the transition of wetlands for agriculture and few cases deal with the conversion from agriculture into protected zones. Moreover, interactions between drivers add to the complexity of land-use change processes. These interrelationships are conditioned by institutions and policies. In particular, the market-oriented reforms adopted by many developing countries in the 1980s and 1990s seem to have had an important role in altering land use, while impacts of more recent policies need to be better explored. Many studies rely on small samples and face problems of internal validity. Despite these weaknesses, the literature points at micro-level economic growth, for example in income and capital endowments, as a strong catalyst of human induced land-use change. However, the review suggests that-across the different studies and cases-there is considerable heterogeneity in the relationship between these factors and land-use change.

Land-use changes have dramatically transformed tropical landscapes. We describe an ecological-economic land-use change model as an integrated, exploratory tool used to analyze how tropical land-use change affects ecological and socio-economic functions. The model analysis seeks to determine what kind of landscape mosaic can improve the ensemble of ecosystem functioning, biodiversity, and economic benefit based on the synergies and trade-offs that we have to account for. More specifically, (1) how do specific ecosystem functions, such as carbon storage, and economic functions, such as household consumption, relate to each other? (2) How do external factors, such as the output prices of crops, affect these relationships? (3) How do these relationships change when production inefficiency differs between smallholder farmers and learning is incorporated? We initialize the ecological-economic model with artificially generated land-use maps parameterized to our study region. The economic sub-model simulates smallholder land-use management decisions based on a profit maximization assumption. Each household determines factor inputs for all household fields and decides on land-use change based on available wealth. The ecological sub-model includes a simple account of carbon sequestration in above-ground and below-ground vegetation. We demonstrate model capabilities with results on household consumption and carbon sequestration from different output price and farming efficiency scenarios. The overall results reveal complex interactions between the economic and ecological spheres. For instance, model scenarios with heterogeneous crop-specific household productivity reveal a comparatively high inertia of land-use change. Our model analysis even shows such an increased temporal stability in landscape composition and carbon stocks of the agricultural area under dynamic price trends. These findings underline the utility of ecological-economic models, such as ours, to act as exploratory tools which can advance our understanding of the mechanisms underlying the trade-offs and synergies of ecological and economic functions in tropical landscapes.

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