The experiment was carried out on cultivation patterns of winter wheat and summer corn in Huantai County,Shandong Province,China. The purpose of the study was to understand how soil fertility maintaining practices,such as chemical fertilizer application,the use of organic manure and the return of crop straw to the field affected soil microbial biomass carbon(MBC) dynamics in a low production agro-ecosystem of northern China.
But with the extension of time, iodosulfuron-methyl sodium was decreased in soil, its effects on urease, neutral phosphatase and microbial biomass carbon are diminished gradually after 14 days, and slowly become consistent with CK.
There is also a marked seasonal variation in the amount of soil microbial biomass carbon, but with the highest (644±71?μg C g-1 soil) and lowest (270±24?μg C g-1 soil) values occurring in the winter and summer, respectively.