Agent-based modeling of land-use changes and vulnerability assessment in a coupled socio-ecological system in the coastal zone of Sri Lanka

In recent decades, the different impacts of global change have led to an increased exposure and vulnerability of coupled socio-ecological systems (SES) to various disturbances and stressors. Human-induced land-use and land-cover changes (LUCC) are an important factor contributing to the vulnerability of such systems. It is therefore reasonable to analyse vulnerability and LUCC in a combined effort. In this study, projections for future LUCC around an estuary in southwestern Sri Lanka were developed. In a subsequent step, the vulnerability of the coupled coastal system to natural hazards was analyzed based on the effects of the tsunami in December 2004. Changes in land use and land cover are the most important impacts of human activities on the earth system, with mostly negative consequences for both ecosystems and social systems. Awareness has grown about the complexity of the driving forces of LUCC, and various modeling approaches have been developed for generating scenarios on different spatial scales. Agent-based models (ABMs) with their focus on the simulation of human decision making and the interdependencies between humans and their environment are seen as a promising and flexible approach. They are best capable of capturing the complexity of coupled SES and of providing a natural description of the systems under consideration. This study employed the Land-Use Dynamics Simulator (LUDAS), an ABM consisting of four modules, which was developed in 2005 for an upland watershed in central Vietnam. In addition to the household and the landscape modules, the policy component captures land-use related policies and other external parameters that impact decision making with respect to land use. The decision-making sub-module as the core of the model simulates the decision-making processes of the household agents. First, LUDAS was modified according to different biophysical and socio-economic circumstances in the coastal study region. Current land use was analyzed with high-resolution satellite images (Ikonos), while ...