褐煤腐殖酸对旱作燕麦土壤微生物量碳、氮、磷含量及土壤酶活性的影响

Effects of Applying Brown Coal Humic Acid on Soil Enzyme Activity and Microbial Biomass C,N and P Content of Oat in Dry Farming

以燕麦坝莜一号为试验材料,设置不施褐煤腐殖酸常规处理（CK）,仅2011年施用腐殖酸,连续2年、连续3年、连续4年施用腐殖酸,以研究腐殖酸对土壤微生物量及酶活性的影响,从而明确腐殖酸对土壤生物学性状的改善效果。试验结果表明,连续多年施用腐殖酸可增加燕麦苗期土壤微生物生物量碳、氮、磷含量,增强土壤蔗糖酶、脲酶、过氧化氢酶活性,有利于培肥土壤,促进土壤中有机物质的分解和转化以及土壤碳、氮等养分的循环,达到提高土壤质量的目的。不同施用年限腐殖酸对土壤酶活性及微生物量的影响不同,连续施用腐殖酸4年的作用优于连续施用3年、2年、1年,4种处理均优于CK处理,说明土壤腐殖酸的累积效应对土壤微生态环境的改善起到积极的作用,其中多年施用腐殖酸对改善10~20cm土壤脲酶活性、微生物生物量氮含量作用显著,能为作物根系生长提供充足的氮素。试验发现土壤酶活性与土壤微生物量之间具有很好的相关性,土壤酶活性可以作为评价土壤微生物量高低的指标。

This experiment was conducted with oat variety Bayou No. 1 as material. For studying the effects of applying humic acid on soil enzyme activity and microbial biomass C and N and P, and defining effect of humic acid on the improvement of the soil biological properties, not applying humic acid was taken as conventional treatment （CK） ,following as application of humic acid only in 2011 （HA1）, application of humic acid 2 years in a row （ HA2）, application of humic acid 3 years in a row （ HA3 ）, application of humie acid 4 years in a row （HA4）. The results showed that applying humic acid for many years could increase the oat seedling microbial biomass C and N and P, enhanced activities of soil invertase and urease and catalase enzymes, as well as benefit soil fertility and the circulation of soil carbon, nitrogen and other nutrients, finally achieved the purpose of improving the quality of the soil. Effects of soil enzyme activity and microbial biomass with different fixed number of year of HA were different. The influence of applying humic acid for 4 years continuously was superior to 3 years and 2 years and 1 year, and four kinds of treatment were better than CK, indicating the cumulative effects of the soil with humic acid played a positive role to improve the soil micro ecological environment. After applying humic acid for many years, urease activity and microbial biomass N in 10 -20cm soil was significantly improved, to provide sufficient nitrogen for crop root growth. It was found that soil enzyme activity had a well correlation with soil microbial biomass;Soil enzyme activity could be used as an evaluation index of soil microbial quantity.