内蒙古乌拉特荒漠草原红砂灌丛林引入柠条后地面节肢动物群落结构分布特征

The introduction of Caragana korshinskii shrubs to degraded Reaumuria soongorica shrubland on the Urat desert steppe in Inner Mongolia is an important ecological restoration measure. It is important to determine how introduced C. korshinskii shrubs affect the structure and diversity of ground-active arthropod communities in natural R. soongorica shrublands to understand their roles in biodiversity conservation and the restoration of degraded ecosystems in this region. In this study, we determined the effects of introduced C. korshinskii and environmental factors on the composition of the ground-active arthropod community in R. soongorica microhabitats on the natural desert steppe by analyzing specimens collected in pitfall traps in spring, summer, and autumn in 2018. In total, 560 individual ground-active arthropods were captured, belonging to 23 families and 10 orders. The main groups were Tenebrionidae and Formicidae, accounting for 41.07% and 22.14% of all collected arthropods, respectively. There were 10 common groups accounting for 32.68% of all collected arthropods, and 11 rare groups accounting for 4.11%. The community composition of ground-active arthropods differed among R. soongorica shrubs, C. korshinskii shrubs, and bare microhabitats. For example, Lycosidae and Clubionidae were present only under C. korshinskii shrubs, and Aphodiidae and Neobisiidae were present only in bare microhabitats. There was no significant difference in the number of arthropods, groups, Shannon-Wiener index, and Simpson's index among R. soongorica shrubs, C. korshinskii shrubs, and bare microhabitats (P>0.05). The Jaccard index of ground-active arthropod communities ranged from 0.65 to 0.71, indicative of strong similarity among R. soongorica shrubs, among C. korshinskii shrubs, and among bare microhabitats. The results of redundancy analysis and partial redundancy analysis showed that soil pH was the main environmental factor affecting the distribution of ground-active arthropods. Our findings indicated that introduced C. korshinskii shrubs in the R. soongorica shrubland on the Urat desert steppe affected the community composition of ground-active arthropods. However, the introduced plants had little effect on the number of individuals and groups and on the diversity distribution of ground-active arthropods, indicating that introduced C. korshinskii shrubs have limited effects on the recovery of ground-active arthropod diversity.