Small patches are hotspots for biodiversity conservation in fragmented landscapes

Abstract In the past two decades, the agro-pastoral ecotone of northern China has experienced dramatic habitat loss and fragmentation, and patches of remaining grassland have formed. However, it is still unclear how to prioritize biodiversity conservation in the remaining grassland patches in this fragmented landscape. Here, we investigated 84 remaining grassland patches in the Tabu River Basin, a typical area of agro-pastoral ecotone of northern China. To determine the conservation priorities of these remaining grassland patches, we used a new conservation criterion called ecological uniqueness based on beta diversity. We further explored the impact of local habitat, dispersal process, and patch characteristics on ecological uniqueness. Our results showed that turnover was the dominant component of regional beta diversity (accounting for 81.9%). We identified 13 hotspots patches with high conservation priority due to their significant ecological uniqueness, 9 of which were small patches (