CONVERSION OF WETLANDS TO FARMLAND AND FORESTS REDUCES SOIL MICROBIAL FUNCTIONAL DIVERSITY AND CARBON USE INTENSITY

Changes in land use types typically lead to changes in soil ecosystem functions, and soil microorganisms can sensitively reflect soil quality and the evolution of different ecosystem functions.To characterize the impact of land use changes on the microbial function of wetlands, our study assessed three typical land use types (wetland, farmland, and forest land) in the Sanjiang Plain, and Biolog microplate technology was used to study the changes in the use intensity and functional diversity of different soil microbial carbon sources, as well as their relationship with soil physicochemical properties.Our findings indicated that the physical and chemical properties of soil changed significantly in different land use types (P < 0.05).The functional diversity and carbon source metabolism of wetland soil were significantly higher than those of farmland and forest.Furthermore, the utilization intensity of compound carbon sources was significantly higher than that of forests and farmland, whereas amino acids, esters, alcohols, amines, and acid carbon sources did not change significantly.Soil water content, total phosphorus, organic carbon, available phosphorus, and other physical and chemical factors affected soil microbial function in different land use types.This study provides key insights into the mechanisms through which land use changes affect soil microbial functions in the Sanjiang Plain, and it also serves as a theoretical basis for the protection and sustainable utilization of wetlands in the future.