Study On The Diversity Distribution Characteristics And Indicator Function Of Carabids In Different Stands Of Temperate Forests In Northern Chin

Temperate forests in China have experienced 50-60 years of logging history,and most of the forest types are secondary forest type in recovery.The forest state is unstable,and climate change has a great impact on forest environmental conditions.Ground beetle is an indicator species in the study of natural ecosystem and biodiversity,and a key species in the study of biodiversity characteristics of environmental change.In this study,5 nature reserves were selected in the temperate zone of China,namely,Liaoheyuan reserve,Donglingshan reserve,Baishilazi reserve,Mudanjiang reserve and Great Hinggan Mountain reserve.Three forest types,coniferous forest,broad-leaved forest types and mixed coniferous and broad-leaved forest,with different life forms as the main dominant tree species,were selected in each reserve,with a total of 15 forest types.A total of 10896 ground beetles belonging to 26 genera and 91 species were captured by traps during the active period of ground beetles.By using a diversity index,β diversity index,ANOVA analysis of variance,indicator analysis and species symbiotic network,we analyzed the distribution differences of richness,diversity,functional diversity of the ground beetles at different study scales.To explored the change mechanism of ground beetle diversity and species coexistence characteristics.To explored the environmental indicator species groups and environmental change monitoring species groups in different reserve,and combined with research conclusion some suggestions.The results showed that:(1)There were significant differences in ground beetle individual distribution among different forest types and reserves.Mudanjiang reserve had the highest diversity index.Mixed forest and broad-leaved forest had higher ground beetle species diversity and lower ground beetle turnover.(2)The individual proportion of small size ground beetle and the abundance of large and small beetle were higher in Great Hinggan Mountain reserve and Mudanjiang reserve.The phytophagous beetle was more abundant in broad-leaved forest,while the predatory beetle was more abundant and diverse in broad-leaved forest and mixed coniferous and broad-leaved forest.(3)The results of ground beetle indicator species and symbiosis network show that the consistent demand of beetle group 1 for environmental conditions linked to the natural environment conditions in Liaoheyuan reserve;survival and reproduction of beetle group 2 have certain dependence of part of the environment conditions in Liaoheyuan,Mudanjiang,and The greater hinggan mountain reserves;the ground beetle species in group 3 were more suitable to live in Mudanjiang reserve.By discussing the research results,the following conclusions are drawn:(1)Broadleaf forest and mixed forest provided abundant food resources,and the ground beetle could obtain enough food resources within a limited turnover range,and the species and individual of ground beetle could be more than that of coniferous forest;(2)The Great Hinggan Mountains and Mudanjiang reserves were more suitable for the survival of small size ground beetle,and the broadleaf forest types provided suitable environmental conditions for the survival of a variety of feeding beetle;(3)A total of 27 indicator species and 3 symbiotic species of ground beetle were found in 5 reserves.The ecological species group composed of Amova,Amvio,Cabil,Casch,Casei,Drqua,Dyhio,Lenig,Nebis,Prpro,Ptjan,Syago,Trcor and Agsp2 could be used as the indicator species group of environment conditions which is similar to Mudanjiang reserves.The ecological species group composed of Cavie,Cahum,Ptexi,Ptsax and Ambru could be used as the indicator species of the tenebrio community in cold environment.Cajan,Cavla and Syorb could be used as markers of degraded habitats,with Cajan indicator values up to 1.00(P<0.0001),which is recommended as a key species for environmental monitoring in this area.Our results emphasize the importance of differentiated conservation measures at the reserve level,or more precisely at the forest type level,for the protection of forest species.Therefore,it is of great significance to understand the characteristics of ground beetle distribution at different levels and unify the commonness of characteristics in different regions,so as to formulate the most appropriate strategies for forest beetle diversity conservation and restoration.In addition,the ecological species groups of ground beetle in different reserves provided important theoretical basis for indicating environmental characteristics and monitoring environmental changes.Future conservation and restoration of forest species diversity should focus on maintaining native species and further supporting the entry of residual populations of forest specialized species into the recovering forest environment.At the same time,according to the environmental characteristics of different forest types,the body size,feeding habits and habitat breadth of the ground beetle species to be introduced should be taken into consideration to improve ecosystem function and resilience.