EFFECTS OF GREEN MANURE CONTINUOUS APPLICATION ON SOIL MICROBIAL BIOMASS AND ENZYME ACTIVITY

A three-year field experiment was carried out to study the effects of green manure application on the soil microbial biomass carbon, nitrogen and soil enzyme activities in order to provide a theoretical basis on low-carbon agriculture, environment-friendly agriculture and promote the sustainable development of tobacco production. Six treatments were set and were: check (CK) (contrast, no application of green manure), T1 (application of ryegrass only 1 year), T2 (application of ryegrass 2years), T3 (application of oats 2years), T4 (application of ryegrass 3years), and T5 (application of oats 3years), which was based on continuous planting oats and ryegrass (Lolium multiflorum L.) in our experiment. The results showed that soil microbial biomass carbon, nitrogen, and the activity of soil urease, acid phosphatase (ACP), sucrase, and catalase increased with each year and with the application of green manure. Compared with the control, after the application of green manure the content of soil microbial biomass carbon and nitrogen increased 1.94%-93.07% and 2.30%-145.07%, respectively, and the activity of soil urease, ACP, sucrase, and catalase increased 1.45%-56.52%, 2.34%-33.17%, 0.96%-172.66%, and 3.33%-85.71%, respectively. Correlation analysis indicated that soil microbial biomass carbon and soil enzymes activity had certain relevance that showed the dynamic process of soil microbial biomass and enzyme activity were coordinate with the decomposition process of green manure and the absorption of mine nutritional to tobacco plant. The results demonstrate that continuous application of green manure could increase soil biological fertility level.