The Microbiological Properties In High-yield Fields Soil Of Piedmont Plain Of Hebei Province During Wheat-Maize Rotation

The groverment pay more attention to food security to meet economic development and population increase recently. However, the long-term intensive agricultural processes made soil in potential health risks. The soil microbial characteristics was known as bioindicator of soil health, therefore, study of soil microbial characteristics in high- yield fields is of great significance.This research was conducted in existed high-yield fields and the transforming middle-and-low-yield fields of piedmont plain in Hebei province under the conditions of straw returned. The soil microbial biomass and main enzymes'activities as indexes of soil microbial characteristics were explored in different soil layers and in the key growth stages of wheat-corn. The main results were as follows:(1) Soil microbiology characteristic in existed high-yield fields appeared better situation than the conventional fields. The dynamics of soil microbial properties in the rotation of wheat-maize showed that soil enzyme activity and soil microbial biomass were stronger in the existed high-yield fields at rapid growing stage of crops.(2) The transformation capacities of organic carbon, organic nitrogen and organic phosphorus in high-yield fields soil were better than those in conventional fields soil. In the conditions of straw returning, the substrate carbon could be utilized better in high-yield fields soil, which was benefit to soil carbon cycle. The microbial biomass phosphorus in high-yield fields was significantly higher than that of conventional fields. It indicated that the organic phosphorus could be used more optimal in high-yield fields.(3) In the cultivating process of high-yield fields, dynamics of soil microbial characteristics did not changed significantly because of different types of water and nutrients management. The application of organic and inorganic fertilizer made the soil with good microbiology characteristics and the crops with yields.(4) In this study, water-fertilizer effective management (D), which included the organic fertilizer application, optimal chemical fertilizers application, trace elements supplementr and reasonable irrigation, was suitable for transforming the middle-and-low-yield fields to high-yield fields in this area.