Land use patterns and related carbon losses following deforestation in South America
Sy, V. De; Herold, M. ; Achard, F. ; Beuchle, R. ; Clevers, J.G.P.W. ; Lindquist, E. ; Verchot, L. - \ 2015
Environmental Research Letters 10 (2015)12. - ISSN 1748-9326
deforestation - forest carbon loss - land use - proximate causes - REDD+ - remote sensing - South America
Land use change in South America, mainly deforestation, is a large source of anthropogenic CO2 emissions. Identifying and addressing the causes or drivers of anthropogenic forest change is considered crucial for global climate change mitigation. Few countries however, monitor deforestation drivers in a systematic manner. National-level quantitative spatially explicit information on drivers is often lacking. This study quantifies proximate drivers of deforestation and related carbon losses in South America based on remote sensing time series in a systematic, spatially explicit manner. Deforestation areas were derived from the 2010 global remote sensing survey of the Food and Agricultural Organisation Forest Resource Assessment. To assess proximate drivers, land use following deforestation was assigned by visual interpretation of high-resolution satellite imagery. To estimate gross carbon losses from deforestation, default Tier 1 biomass levels per country and eco-zone were used. Pasture was the dominant driver of forest area (71.2%) and related carbon loss (71.6%) in South America, followed by commercial cropland (14% and 12.1% respectively). Hotspots of deforestation due to pasture occurred in Northern Argentina, Western Paraguay, and along the arc of deforestation in Brazil where they gradually moved into higher biomass forests causing additional carbon losses. Deforestation driven by commercial cropland increased in time, with hotspots occurring in Brazil (Mato Grosso State), Northern Argentina, Eastern Paraguay and Central Bolivia. Infrastructure, such as urban expansion and roads, contributed little as proximate drivers of forest area loss (1.7%). Our findings contribute to the understanding of drivers of deforestation and related carbon losses in South America, and are comparable at the national, regional and continental level. In addition, they support the development of national REDD+ interventions and forest monitoring systems, and provide valuable input for statistical analysis and modelling of underlying drivers of deforestation.
Integrated analysis of land use changes and their impacts on agrarian livelihoods in the western highlands of Kenya
Mutoko, M.C. ; Hein, L.G. ; Bartholomeus, H. - \ 2014
Agricultural Systems 128 (2014). - ISSN 0308-521X - p. 1 - 12.
soil fertility management - proximate causes - cover - deforestation - africa - sustainability - expansion - dynamics - district - growth
Land degradation is affecting rural livelihoods across sub-Saharan Africa. Promoting sustainable land management requires a thorough understanding of land use change drivers, processes and effects. However, in most African countries reliable data for such investigations are missing. We therefore test an integrated approach to analyse land use dynamics, combining remote sensing images, an in-depth quantitative survey, stakeholder interviews and local statistics. We analyse land dynamics and agricultural production over a 25-year period in Vihiga District, Western Kenya. Specifically, we examine how land use has changed in this period, the main drivers for land use change, and the main effects of these changes on agricultural production. Vihiga District is one of the most densely populated rural areas in Africa. We find that the district has undergone rapid land use change in the past 25 years. In particular, there has been a major conversion of forest and bare land to agricultural land use. Often, it is stated that increasing population pressure triggers agricultural intensification; however, we find little evidence of such a process in Vihiga District. Productivity of tea and, to a lesser extent, vegetables increased but the yields of maize and beans, the most common crops, fluctuated around a ton per hectare. Overall, per capita food crop production dropped by 28% during the past two decades. Our study shows that high and increasing population pressures do not necessarily lead to agricultural intensification, and that there is a need to consider more explicitly off-farm income in development and land management policies and projects.
Causal chains, policy trade offs and sustainability: Analysing land (mis)use in seven countries in the South
Nesheim, I. ; Reidsma, P. ; Bezlepkina, I. ; Verburg, R.W. ; Abdeladhim, M.A. ; Bursztyn, M. ; Chen, L. ; Cissé, Y. ; Feng, S. ; Gicheru, P. ; König, H.J. ; Novira, N. ; Purushothaman, S. ; Rodrigues-Filho, S. ; Sghaier, M. - \ 2014
Land Use Policy 37 (2014). - ISSN 0264-8377 - p. 60 - 70.
environmental kuznets curve - integrated assessment - ecosystem services - proximate causes - narok district - framework - deforestation - conflict - china - kenya
The need to enhance sustainable development of land use is more urgent than ever; specifically in developing countries where poverty and land degradation are often interlinked. To promote a common understanding of land use problems by experts, stakeholders and decision makers, it is essential to understand the system characteristics, including the complex feedbacks between drivers and impacts. To enhance sustainable development, appropriate policies need to be identified. In this paper, we analysed and compared seven case studies in Kenya, Mali, Tunisia, China, India, Indonesia and Brazil, representing different biophysical and socio-economic conditions and challenges. We analysed Driver Pressure State Impact Response (DPSIR) story lines of the land use problems, policy priorities and value trade-offs as identified by stakeholders and experts in National Policy Forums. Important drivers of land use change impacting main land use problems among the case studies were economic growth, technological development, immigration and agricultural intensification, in addition to existing policies. Of the latter the most important were related to domestic support through various forms of subsidies or access to credit, land tenure polices and liberalization policies. In the policy prioritization, the value trade-offs made by the National Policy Forums emphasize the environment rather than increased economic production. It is recognized that the environment needs to be improved to maintain and improve economic production in the long term, both in agriculture and in other sectors.
Comparing inductive and deductive modeling of land use decisions: principles, a model and an illustration from the Philippines
Overmars, K.P. ; Groot, W.T. de; Huigen, M.G.A. - \ 2007
Human Ecology 35 (2007)4. - ISSN 0300-7839 - p. 439 - 452.
household life-cycles - tropical deforestation - proximate causes - forest fringe - cover change - framework - dynamics - ecology
Understanding the causes of land use change is of great importance for issues of tropical deforestation, agricultural development and biodiversity conservation. Many quantitative studies, therefore, aim to link land use change to its causal `driving forces.¿ The epistemology of virtually all these studies is inductive, searching for correlations within relatively large, sometimes spatially explicit, datasets. This can be sound science but we here aim to exemplify that there is also scope for more deductive approaches that test a pre-defined explanatory theory. The paper first introduces the principles and merits of inductive and more deductive types of land use modeling. It then presents one integrated causal model that is subsequently specified to predict land use in an area in northeastern Philippines in a deductive manner, and tested against the observed land use in that area. The same set of land use data is also used in an inductive (multinomial regression) approach. With a goodness-of-prediction of 70% of the deductive model and a goodness-of-fit of 77% of the inductive model, both perform equally well, statistically. Because the deductive model explicitly contains not only the causal factors but also the causal mechanisms that explain land use, the deductive model then provides a more truly causal, as well as more theory-connected, understanding of land use. This provides land use scholarship with an invitation to add more deductive (theory-driven and theory-building) daring to its methodological repertoire.
Analysis of land use drivers at the watershed and household level: linking two paradigms at the Philippine forest fringe
Overmars, K.P. ; Verburg, P.H. - \ 2005
International Journal of Geographical Information Science 19 (2005)2. - ISSN 1365-8816 - p. 125 - 152.
tropical deforestation - proximate causes - use patterns - cover change - costa-rica - model - technology - adoption - systems - amazon
Land use and land cover change (LUCC) is the result of the complex interactions between behavioural and structural factors (drivers) associated with the demand, technological capacity, social relations and the nature of the environment in question. Although no general theory of land use change exists, different disciplinary theories can help us to analyse aspects of LUCC in specific situations. However, paradigms and theories applied by the different disciplines are often difficult to integrate and their specific research results do not easily combine into an integrated understanding of LUCC. Geographical approaches often aim to identify the location of LUCC in a spatially explicit way, while socio-economic studies aim to understand the processes of LUCC, but often lack spatial context and interactions. The objective of this study is to integrate process information from a socio-economic study into a geographical approach. First, a logistic regression analysis is performed on household survey data from interviews. In this approach the occurrence of the land use types corn, wet rice and banana is explained by a set of variables that are hypothesised to be explanatory for those land use types, with fields as the unit of analysis. The independent variables consist of household characteristics, like ethnicity and age, and plot and field information, like tenure, slope and travel time. The results of these analyses are used to identify key variables explaining land use choice, which subsequently are also collected at watershed level, using maps, census data and remote sensing imagery. Logistic regression analysis of this spatial dataset, where a ten percent sample of a 50 by 50 m grid was analysed, shows that the key variables identified in the household analysis are also important at the watershed level. Important drivers in the study area are, among others, slope, ethnicity, accessibility and place of birth. The differences in the contribution of the variables to the models at household and watershed level can be attributed to differences in spatial extent and data representation. Comparing the model with a mainstream geographical approach indicates that the spatial model informed by the household analysis gives a better insight in the actual processes determining land use than the mainstream geographic approach
Accessibility and land-use patterns at the forest fringe in the northeastern part of the Philippines
Verburg, P.H. ; Overmars, K.P. ; Witte, N. - \ 2004
Geographical Journal 170 (2004)3. - ISSN 0016-7398 - p. 238 - 255.
tropical deforestation - individual accessibility - western honduras - proximate causes - cover change - dynamics - models - satellite - household - amazon
Accessibility is considered to be one of the most important determinants of use and land-cover change. In rural land-use change studies, the accessibility situation is often described by simple measures of the distance to a location of interest. In this paper, different measures of access are tested for a rural area at the forest fringe in the northeastern Philippines. The accessibility measures addressed range from simple distance measures to land-use type specific transport costs and a population potential measure. The different measures are tested based on their capacity to explain the spatial pattern of different land-use types. A comparison of the findings based on a spatial analysis and an analysis of household level data is made. It is concluded that the relation between land use and accessibility is dependent on the specific characteristics of the different land-use types. The (dis-)advantages of the use of the different accessibility measures are discussed.