Diversity of ground-dwelling beetles (Coleoptera) in restored habitats in the hill and gully area of Loess Plateau, Ningxia Hui Autonomous Region

Abstract

The aim of this study was to probe into changes in diversity of ground-dwelling beetles (Coleoptera) and their relation to environmental variables within restored habitats in the hill and gully area of Loess Plateau, Ningxia Hui Autonomous Region, China. An investigation of ground-dwelling beetle communities was carried out using pitfall traps in six habitats including shrub/grassland, tree/shrub mix, fuel-wood forest, naturally restored grassland, plantation forest, and level terraced field in July and August, 2013. We found that species richness and abundance of individual ground-dwelling beetles was higher (P<0.05) in the shrub/grassland, tree/shrub mix, and fuel-wood forest compared to the other three stands. Species richness of ground-dwelling beetles was markedly lower (P<0.05) in naturally restored grassland, plantation forest and level terraced field, whereas the abundance of individual ground-dwelling beetles were higher in plantation forest and level terraced field than in naturally restored grassland. Jaccard indices revealed a high level of similarity amongst shrub/grassland, tree/shrub mix, and fuel-wood forest stands, and then between plantation forest stands and level terraced fields. Multiple linear regression analyses showed that herbaceous biomass, cover of shrub species and soil water content were the key factors affecting species richness of ground-dwelling beetles, while it was canopy cover and leaf litter depth that most affected total abundance. Canonical correspondence analysis (CCA) showed that the cover and depth of leaf litter, cover of canopy and herbaceous layers were important determinants of species abundance and composition of beetle communities. 第 4 期 杭佳等: 宁夏黄土丘陵区不同生态恢复生境地表甲虫多样性 517 In conclusion, conversion to shrub/grasslands may be one option for raising ground-dwelling beetle diversity in the hill and gully area of Loess Plateau, Ningxia.