Impact of spatial scale on the identification of critical habitat patches for the maintenance of landscape connectivity

Abstract

An increasing awareness of the effects that the spatial scale of source maps may have on landscape analyses has lately prompted much research on this topic. Nevertheless, previous studies have just focused on describing the variations of different landscape metrics with scale, while the scale impact on the actual decision-making and landscape planning derived from connectivity analyses has not yet been tackled. We examined the influence of varying minimum mapping unit (MMU) and spatial extent on the prioritization of patches by their importance for the conservation of overall landscape connectivity, according to 10 different metrics as management support tools. We analyzed the forest patches distribution in three study zones within Spain with diverse spatial configuration from CORINE land cover data. Our results showed that the probability of connectivity, the area-weighted flux and the integral index of connectivity are the most robust metrics in terms of patches prioritization, while the results provided by the number of components, graph diameter and class coincidence probability are strongly scale-dependent. We found that scale sensitivity of the overall landscape metric value is not related to scale sensitivity in terms of patches prioritization. We provide guidelines for an appropriate selection of connectivity metrics and scale of analysis for landscape conservation planning and related applications.