Study On The Diversity Of Soil Animals In Different Landscape Of Yani Wetland

As one of the three major ecosystems,wetland is rich in hydrological,animal and plant resources and is called "kidney of the earth".As the decomposer and energy converter of wetland ecosystem,soil animals can not only accelerate the nutrient cycle of soil environment,but also serve as an important ecological indicator of environmental change and sustainable development.The dynamics of soil animal community can affect the vegetation community and soil physical and chemical properties,and the ecological changes of vegetation community and soil physical and chemical properties can also react to the diversity of soil animal community.Yani Wetland is located at the intersection of Niyang River and Yarlung Zangbo River in southeastern Tibet.It is rich in hydrological resources and rich in animal and plant resources,and is an important part of Tibet Wetland.At present,there are many studies on the effects of different landscape environments on soil animal diversity,but there are few reports on soil animals in Yani wetland.Therefore,in this experiment,soil animals in four typical landscapes(woodland(FD),farmland(NT),sandy land(GD)and shrub(BW))were selected as research objects in Yani Wetland from May to August,2 022.Based on the methods of field investigation and indoor analysis,soil bulk density,water content,organic matter,p H,total nitrogen,total potassium and water content were selected.The main results are as follows:(1)A total of 2 621 soil animals belonging to 117 families(groups)of 10 classes,22 orders were captured in 4 landscape plots of Yani Wetland.Acariformes and Collembola are the dominant groups,accounting for 31.25% and 31.55% of the total number of soil animals respectively.(2)The monthly variation of individual number,group number,diversity,evenness,dominance and richness of soil animals in different landscape plots was the highest in July.The soil animal diversity index of0～10cm soil layer in each landscape plot was significantly higher than that of 10 ～ 20 cm soil layer(P < 0.05),showing obvious surface aggregation characteristics.(3)Among the four landscape types of soil animals in Yani wetland(woodland(FD),farmland(NT),sandy land(GD)and shrub(BW),except woodland(FD),the individual numbers of other three landscape types showed significant monthly differences(P < 0.05);Except for the sandy land(GD),the number of soil animal groups in the other three landscape types showed significant monthly differences(P < 0.05),indicating that the degree of human disturbance such as regular spraying of pesticides and frequent agricultural activities,and the influence of natural factors such as river erosion and climate change have great influence on the temporal changes of soil animal individuals and groups.(4)Among the four landscape types(woodland(FD),farmland(NT),sandy land(GD)and shrub(BW)),there are significant differences in diversity,evenness and richness in different months(P < 0.05),which indicates that the diversity of soil animals changes greatly in different months.(5)The spatial distribution of soil animal community in Yani wetland is different in different landscape types,and the similarity in different landscape types is low.(6)Excessive natural factors and human interference will affect the complexity of soil animal community structure.In this experiment,the farmland is most affected by human disturbance,and the difference of total potassium(TK)and soil water content(Mc)in different soil layers is not significant,which reduces the difference of soil fauna affected by two environmental factors.Based on the study of soil animal diversity in different landscapes of Yani wetland,it is found that soil organic matter and p H are important environmental factors affecting soil animal diversity,and frequent agricultural activities and serious river erosion will affect the time dynamics of soil animal community.In addition,too high soil water content will also affect the development of soil animal diversity.