Regional sets of diverse, specialized ground beetle and plant assemblages recolonise China's restored temperate forest landscapes

Abstract

Following the historic destruction of China's forests, large protected forest landscapes have been reestablishment across the country in recent decades. Currently, the species assemblages inhabiting these landscapes remain widely unknown. Here, we aim to establish whether the new temperate forest landscapes in Eastern China, composed of plantation, secondary and remnant mature forest patches, are dominated by widely distributed habitat generalists, widely distributed habitat specialists, or by sets of highly localized forest habitat specialist species, using vascular plants and ground beetles as case studies. We sampled plants and ground beetles on 159 plots representing different forest types distributed across ten study regions. The Chord-normalized expected species shared (CNESS) dissimilarity for beetles and Jaccard dissimilarity for plants were calculated to establish species' turnover patterns, while we used structural equation and multiple regression models for dissimilarity matrices to establish the relative importance of location, elevation and biotic interactions in explaining largescale distribution patterns of species assemblages. Both taxa showed highly regionalized recruitment, with plant communities responding strongly to latitude, and to geographic location in general, while the composition of ground beetle communities appeared strongly governed by both the composition of the vegetation and study plot location. Both assemblages showed a distinct lack of widespread habitat generalists. Our results demonstrate for the first time that local assemblages of forest specialist species appear to have survived last century's deforestation in unknown refugia before successfully re-colonizing China's restored forest ecosystems. We argue that restored forest landscapes can play a significant role in the conservation of temperate China's biodiversity at both local and regional scales.