Microbial biomass C,N,P of farmland soils in different land uses and croppingsystems in Dongting Lake region pH and the exchangeable aluminum content in acid soils as affected by parent materials and cropping systems Evaluation on comprehensive benefits of multiple cropping systems on upland red soil Relationship between Crop Productivity and Ecological Factors in Poplar-Crop Intercropping Systems in Haihe Lowland Area Review of research on nutrient contribution and recovery in alley cropping systems Changes in the dominant pathogens causing Fusarium dry rot of potato in rhizospheric soil under continuous potato cropping systems based on real-time quantitative PCR Assessment of competition for water, fertilizer and light between components in the alley cropping system