冀东稻区基于低温复合菌系HT20的秸秆腐解因素研究

为探索低温启动型且具有纤维素强分解能力的复合菌系HT20作用下秸秆腐解的影响因素。采用室内培养试验,通过响应曲面优化法Box-Behnken设计建立HT20添加量、温度、秸秆含水率和尿素添加量与秸秆腐解率之间的模型,结合大田微区模拟试验验证HT20实际田间应用效果,并与常用的4种秸秆腐熟剂进行比较。结果表明:秸秆腐解率受HT20添加量、温度、秸秆含水率的影响显著,且各影响因素间交互作用对秸秆腐解率影响显著,尿素添加量与HT20添加量之间交互作用对秸秆腐解率影响不显著。与不添加腐熟剂(CK)和常用腐熟剂相比,HT20腐解速率提高20.10%～81.46%,腐解时间缩短17.62～183.41d,养分提高5.44%～71.49%,微生物数量增加1.57%～76.14%。表明,低温复合菌HT20在冀东滨海稻区还田秸秆腐解中起到了主导作用。研究结果为本地秸秆还田中低温复合菌系HT20的施用提供理论指导,为我国北方稻区秸秆还田提供技术支撑。

Study on Straw Decomposing Factors Based on Cold-adapted Microbial Consortium (HT20) in Rice Production Area of Eastern Hebei

The aim of this study is to investigate the factors influencing straw decomposition by the action of microbial consortium (HT20)which is cold-adapted and has strong cellulose degrading capacity. A laboratory cultivation experiment was conducted and response surface methodology (i.e.,Box-Behnken) was used to derive a model between straw decomposition rate and HT20 addition,temperature,straw moisture content,and urea addition. A field plot experiment was conducted to verify the feasibility of field application of HT20,and decomposition performance of HT20 was compared with that of four common straw-decomposing inoculants. The results showed that the straw decomposition rate was significantly affected by the addition amount of HT20,temperature,and straw moisture content,as well as the interaction between various influencing factors. However,no significant interaction was observed between the addition amount of urea and HT20.Compared with treatments without and with the addition of common decomposing agents,HT20 treatment increased the decomposition rate by 20.10%-81.46%,shortened the decomposition time by 17.62-183.41 days,increased the nutrient content by 5.44%-71.49%,and increased the number of microorganisms by 1.57%-76.14%. Thus,HT20 could play a prominent role in the decomposition of straw returning to the field in the eastern coast inrice production area of Hebei. The results provide theoretical support for the field application of HT20 and technical support for straw returning to field in the rice production regions of North China.