Finding sites meeting compactness and on- and off-site suitability criteria in raster maps

This paper presents an evaluation of the Heuristic for Locating Cells (HLC) [1] for identifying optimal sites in raster maps. The optimal sites are the result of a trade-off between the on-site suitability of individual cells, their spatial configuration, and their off-site impact at the watershed outlet. The evaluation is targeted to a case of reforestation in two sub-basins within the Tabacay catchment in the southern Andes of Ecuador. The case is set up to locate a predefined number of cells 1) forming a compact patch, 2) minimizing sediment reaching the watersheds outlet, and 3) maximizing cell-specific performance, i.c. carbon sequestration and monetary income as a result of reforestation with pine trees. The evaluation confirms that the heuristic is capable of identifying high quality compact patches of cells with maximal on-site performance while minimizing sediment delivery.