Effects of shrub revegetation on ground-active arthropod diversity and trophic structure in the Tengger desert

Abstract

Shrub vegetation and plant species can enhance the abundance and richness of ground-active arthropods. Yet surprisingly little is known about how the distribution and diversity of ground-active arthropods are influenced by plant species used for shrub revegetation in desert ecosystems. In this study, ground-active arthropods were collected using the pitfall trapping method in Caragana korshinskii (CP), Hedysarum scoparium (HP), and Artemisia ordosica (AP) plantations, for which an adjacent mobile sand land (MS) served as the control in the Tengger desert (northwestern China). We found no significant differences in the total abundance of arthropods among the four habitats, whereas the taxonomic richness and Shannon index of ground-active arthropods were significantly (P < 0.05) greater in all three plantations when compared to the MS. The herbivore arthropods were significantly (P < 0.001) more abundant in the AP and MS than either the HP or CP. The predator abundances were significantly (P < 0.05) greater in all three shrub plantations compared with the MS. The detritivore abundances also differed (P < 0.05) across habitats, in the order of HP > CP > AP > MS. The dominant groups in MS, including Tenebrionidae and Buprestidae, were replaced by Formicidae, Melandryidae, and Carabidae in HP; by Formicidae, Carabidae, Chrysomeloidea, and Melandryidae in AP; and by Formicidae and Carabidae in CP. Our results suggested that shrub crown diameter, shrub density, and herbaceous richness together explained the different responses of ground-active arthropod communities to revegetation, highlighting the importance of shrub individual traits in this process for the maintenance of arthropod diversity and trophic structure in desert ecosystems.