Effect Of Humus And Its Fractions In Soil By Different Death Microbial Cells

The humus is the subject of soil organic matter(SOM),which is also one of the most important indicators to measure soil quality;and the change of humus’ s quantity not only is assoiciated with soil fertility,but also can affect the environmental quality. For short-term culture conditions, this paper investigated the effect of microbial biomass carbon(MBC)、humus and its fraction in soil by the addition of different death microbial cells.This study set chernozem as tested materials.Dead bacterial cells(B.mycoides)、dead fungal spores(Trichoderma harzianum)、dead fungal hyphae(Trichoderma harzianum) and dead actinomycete cells(Streptomyces griseus) were inoculated to the soil,and non inoculated microbial control(CK), a total of five treatments for training, periodic sampling. The method of sodium phosphate leaching was selected to extract humus and its fractions, The method of chloroform fumigation and TOC analyzer was applied in analyzing the content of microbial biomass carbon.The thermal oxidation of K2Cr2O7 was adopted to analyze the C contents of Soil organic、HE(HA+FA) and humic acid(HA). To clear the fluence on microbial biomass carbon(MBC)、humus and its fraction in soil by the addition of different death microbial cells,it can provide a theoretical basis to achieve the sustainable development of soil fertility and soil carbon sequestration regulation. The results shows:(1) The content and relative content of MBC is improved by the addition of dead fungal hyphae and dead actinomycete cells.But Dead bacterial cells and dead fungal spores have little influence on the content of MBC,only the relative content of MBC reduces.(2) The extracted quantity of HE all can be promoted by different death microbial cells.(3) Dead fungal spores can promote the extracted quantity of humic acid,but little influence on fulvic acid(FA).However, dead bacterial cells、dead fungal hyphae and dead actinomycete cells can promote the extracted quantity of humic acid,and no effect of fulvic acid.