Identifying priorities under highly heterogeneous environments through species distribution models to facilitate orchid conservation

Abstract

The ecological suitability prediction and analysis of specific taxonomic groups at finer geographic scales provide vital references for identifying and prioritizing biodiversity hotspots, especially for uneven species richness. Yet, in predicting suitability for multi-species or groups by species distribution models (SDMs) under highly heterogeneous environments, species bias may occur cause of the unequal protection status and the spatial autocorrelation processing of occurrences. For this, diversity, and protection hotspots were mapped in the south of the Hengduan Mountains, a significant site for global biodiversity. Specifically, it involved creating a network of 1 km² grid cells spanning the region, counting the orchid species, quantifying the protection value, and classifying attributes by the Jenks Natural Breaks Classification in ArcGIS. Each grid has a 5 and 10 km buffer zone that contains attributes composing the diversity and protection hotspot layers, which were compared to the orchid suitability map modeled by SDMs. Results showed that even though there were extensively suitable habitats for orchids, the model results cannot completely cover the whole diversity and protection hotspots at any scale. Based on the map attributes, multi-scenario conservation planning was proposed, respectively the strict conservation scenario (SS), the economical conservation scenario (ES), and the positive conservation scenario (PS), representing different conservation objectives and efforts. This study identifies the critical areas of ecological suitability, diversity, and protection of orchids that facilitate to display of the fundamental biogeographical patterns in this region, which provides meaningful references for regional or global biodiversity conservation and transferable methods for similar studies.