长期施肥土壤β-葡糖苷酶动力学特性研究

Kinetics of soil β-glucosidase under long-term fertilization

以长期施肥的黑土和棕壤为供试对象,对土壤β-葡糖苷酶动力学特性进行研究.结果表明,土壤β-葡糖苷酶的酶促反应符合一级动力学模型.黑土有机肥处理对土壤β-葡糖苷酶动力学参数影响较大,Km和Vmax值均高于单施化肥和对照处理;与对照相比,化肥处理影响较小.棕壤施用化肥后,Km和Vmax值与其他处理相比均减小,有机肥处理后Vmax和Vmax/Km值增大.2种土壤各施肥处理β-葡糖苷酶的Vmax值与土壤有机质、全氮含量均呈显著正相关关系,并对施肥处理的响应较敏感.

The kinetic characteristics of β-glucosidase were studied in a black soil and a brown soil with long-term fertilization. It was found that the enzymatic reaction of soil β-glucosidase followed first-order kinetics. In the black soil, organic manure fertilization had a greater effect on the kinetic parameters of β- glucosidase, with higher Km and V values than those under chemical fertilizers application and nonfertilization, but less difference was observed between chemical fertilizers application and non- fertilization. In the brown soil, chemical fertilizers application led to lower values of Km and V while organic manure fertilization increased the values of V and Vmax/Km. In all fertilization treatments on the two kinds of soil, V was significantly positive correlated with the contents of soil organic matter and total nitrogen, and was more sensitive to the fertilization treatments than Km.