Abstract:

To provide theoretical basis for rice straw processing technique by decomposition accelerant, effects of treating returned early rice straw by two types of decomposition accelerant, Fuganling and straw-decomposition microbe, on soil chemical and biological characteristics in late rice stage were studied in double rice field in Changsha, Hunan. The main results showed that: Soil nutrients contents were significantly affected by straw-decomposition accelerant (SDA), which mainly showed in increase of soil total N and available K before fully heading and decease of soil available N. SDA evidently affected enzyme activity in soil, while it was related to type of enzyme, type of decomposition accelerant and growth stage of rice. Compared to control, microbial activity in SDA treatments was lower before fully heading, while it was significantly higher after fully heading. Quantity of bacterium was increased, while quantity of epiphyte was decreased. Quantity of actinomycete was increased in straw-decomposition microbe treatment, while it was decreased in Fuganling treatment. Compare to Fuganling, the effects of straw-decomposition microbe on improving activities of soil main enzyme, activities of microbes and soil nutrient content were better.