The Composting Characteristics of Cotton Straws and Maturity Evaluation

Using cotton straws from the Yellow River Delta region as compost materials, the physics, chemistry, biology indexes of cotton straw compost, effected by microorganisms and C/N, were measured periodically and the maturity degree was evaluated. The result showed that the processing effect of microbial agent treatment was not obvious. Compared with CK and microbial agent treatment, the nitrogen treatments could prolong the time of compost temperature (50 ℃) . The cotton straw+ nitrogen+ microbial agent (C:N=25:1) treatment, finished maturity firstly after 84 days, was the optimal treatment. In the cotton straw maturity evaluation, C/N, TOC, TN, T were suitable to be used as optimization indexes, pH, temperature and GI were suitable as general evaluation indexes. The indexs for evaluating the maturity of cotton straw compost was established preliminarily and the scientific guidance for using cotton straw compost was provided. The reasonable utilization of cotton straw for soil modification could reduced CO2 emission by fire in a certain extent.