Soybean cropping patterns affect trait-based microbial strategies by changing soil properties

Abstract

Abstract In agroecosystem, rational cropping pattern is crucial for maintaining soil fertility and improving soil function. Microbial life history strategies determine their responses to soil resource availability, thereby affecting soil nutrient cycling. However, our knowledge about microbial strategies under different management practices is limited. The objective of this study was to explore how microbial functional traits and life history strategies respond to different cropping patterns. We analyzed bacterial, archaeal, and fungal communities as well as their functional traits under different cropping patterns in representative soybean (Glycine max) planting regions across China using high-throughput sequencing and quantitative PCR data. Results showed that intercropping increased soil carbon and nitrogen pools, while rotation reduced soil carbon pool. By analyzing the shared species between keystones and indicators (keystone indicators), the selection of microbial communities by cropping patterns was observed at both taxonomic and functional levels. Intercropping harbored more bacterial and fewer fungal keystone indicators than rotation, which were characterized by special substrate preference in the two systems. Moreover, soil properties oppositely influenced bacterial and archaeal core functional traits, but did not limit fungal core functional traits. The ecological associations between soil properties and microbial functional traits illustrated that bacterial and archaeal life history strategies were affiliated to resource acquisition, while fungi adopted high yield strategy. Taken together, the results indicated that different soybean cropping patterns impacted trait-based microbial life history strategies by changing soil nutrients.