Examining How Long Fallow Swidden Systems Impact Upon Livelihood And Ecosystem Services Outcomes Compared With Alternative Land Uses In The Uplands Of Southeast Asia PDF Download

A spatially explicit multiobjective decision support system, the Spatial Environment and Agricultural Decision Support (SEADS) tool, was developed for use within a geographic information system. SEADS presents decision makers with a toolkit for analyzing how proposed land uses will affect hydrologic, economic, and sustainable development outcomes. Decision makers are therefore better able to consider how the adoption of alternative land uses will incorporate stakeholder's needs and goals. SEADS research and development was carried out in the River Njoro watershed in Kenya's Rift Valley. A principal factor of this approach is that outputs from spatially explicit models are transformed with scoring functions to a dimensionless 0 to 1 scale so that they can be directly compared, regardless of their scale of measurement. The scoring functions transform model values into scores using four mathematical functions: more is better, more is worse, desirable range, and undesirable range. As part of the development of SEADS, the impact of uncertainty in defining these functions was investigated. Scoring function uncertainty interferes with decision making since the same model value can receive widely varying scores, resulting in a different ranking of land use alternatives. A hindrance to effective land use management and natural resources allocation is the poor understanding of feedbacks between population density and natural resources use and the corresponding impacts on ecological systems. To address this weakness, techniques were developed to better represent the spatial distribution of human population within natural boundaries. Freely available census and land cover data sets were analyzed at multiple scales, and improved estimates of population densities in rural areas were attained. Potential impacts on policy making and the utility of such an analysis during the initial decision making phase were highlighted.