Characterization of land degradation processes using airborne laser scanning

Land degradation is a cause for increased concern in many regions around the world, requiring to quantify the geomorphic processes that such regions are undergoing. Even though the processes that influence the surface topography are three dimensional in nature, they are usually monitored in two dimensions using surveying techniques or naive image interpretation. We present in this paper a methodology for quantifying geomorphic processes in the form of soil erosion, channel incision, and the development of collapse sinkholes in high resolution using airborne laser scanning technology. As a study case, we use the Dead Sea region, where lake level drop of more than one meter per year has led to dramatic changes in the surrounding geomorphic system, leading to the destruction of wetland environments, rapid headcuts migration that endanger the natural environment and infrastructure, and development of sinkhole fields, which in some parts halted regional development. We show how laser data is optimal for detecting such phenomena, accurately characterizing them, and determining volume and evolutionary rates all are necessary to understanding their development.