Comparative Study On The Characteristics Of Soil Enzyme Activities And Microbial Communities In Different Wetlands Of Qinghai Lake

Soil microbial and enzyme activity is highly sensitive to environmental factors and can be used as an indicator of soil quality.In wetland ecosystems,material transformation and energy flow are closely related to soil enzymes and soil microorganisms;therefore,studies on soil enzyme activity and microorganisms can provide insight into the response of wetland ecosystems to changes in the soil environment.In this paper,the soil enzyme activity characteristics and microbial community of different（Qinghai Lake marsh wetland（ZZ）,lakeshore wetland（HB）,estuarine wetland（HK）and Qinghai Lake bottom mud（DN））wetlands on the northeastern Tibetan Plateau were investigated by measuring soil sucrose enzymes,urease,polyphenol oxidase,catalase,alkaline phosphatase and soil physicochemical properties combined with macrogenome sequencing.The main results of this paper are as follows.The main results of this paper are as follows:（1）Significant differences（P<0.05）were found between each of the soil peroxidase activity,urease activity,alkaline phosphatase activity,sucrase activity and polyphenol oxidase activity in different wetlands of Qinghai Lake.The levels of the first four enzymes showed that lakeshore wetland>estuarine wetland>marsh wetland>Qinghai Lake bottom mud,and the levels of soil polyphenol oxidase activity were lakeshore wetland(3 408.45±305.45 nmol·h^-1·g^-1)>marsh wetland(2 346.80±208.98nmol·h^-1·g^-1)>Qinghai Lake bottom mud(1 567.09±261.93 nmol·h^-1·g^-1)>estuarine wetland(1 120.40±247.78 nmol·h^-1·g^-1).（2）The relative abundance of soil microbial communities in the different wetlands of Qinghai Lake was greater（75%）than that of the fungal communities（less than 1%）,and the dominant bacterial phylum was Amoeba.Overall,the relative abundance of soil microbial communities in the Qinghai Lake sediment was low.（3）The diversity of soil microbial communities in the different wetlands of the Qinghai Lake showed significant variability,with the Simpson and Berger parker indices of Qinghai Lake bottom mud being higher than those of all three other wetlands,while the Dominance and Shannon indices showed the opposite.（4）Soil total nitrogen,total phosphorus and organic matter had a greater effect on soil sucrase and peroxidase activity,soil organic matter,conductivity and bulk density had a greater effect on soil alkaline phosphatase activity,and soil total phosphorus,total nitrogen and water content had a greater effect on soil polyphenol oxidase activity.（5）There were 89 predicted functional groups predicted for the four FAPROTAX functions of wetland soil microbes in Qinghai Lake,and LEf Se analysis of soil microbial pathways revealed 43 metabolic pathways out of 167 differential pathways.The major differential pathways were Carbon metabolism,Methane metabolism,Starch and sucrose metabolism,Amino sugar and nucleotide sugar metabolism,Butanoate metabolism.