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

Abstract

This paper presents an evaluation of the Heuristic for Locating Cells (HLC) 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.