Optimized allocation of forest restoration zones to minimize soil losses in watersheds.

Increase of water erosion is one of the main problems in watersheds all over the world and directly affects soil and water resources, causing economic and environmental losses. We proposed a combination of Genetic Algorithm and Erosion/Deposition modelling to allocate vegetation zones in order to reduce soil losses within watersheds. In this study, we have used Unit Stream Power Based Erosion Deposition (USPED) model to predict the spatial distribution of erosion and sediment deposition. Based on USPED estimates, Genetic Algorithm optimize site as well size of forest restoration zones in order to reduce soil losses. Proposed approach considered watershed entirely, in a cell-level optimization, to find the best possible arrangement of forest zones. For initial scenario, soil loss estimate was 2.045,55 ton. ha-1. year-1 and after optimization we achieved 52% reduction. Optimized forest zones formed connected and compacted patches, which enable field implementation. Methodology is also applicable to other watersheds around world.