秦岭松栎混交林土壤微生物及酶活性

Soil Microbes and Enzymes in An Oak-Pine Mixed Forest in the Qinling Mountains

为探讨林地土壤生物活性特征及其影响因子,在火地塘林区选择秦岭中山地带广布的松栎混交林为研究对象。采用野外采样和室内分析相结合的方法,测定了林地土壤不同土层细菌、放线菌和真菌的数量,过氧化氢酶、脲酶、蔗糖酶、酸性磷酸酶的活性及相关理化指标含量,分析了它们的变异规律及其之间的相关性,并建立了回归方程。结果表明:3种土壤微生物的数量、4种土壤酶的活性均呈现出随土壤深度的增加而降低的趋势;细菌在土壤微生物群落中占绝对优势,比例高达99%;土壤含水率、有机质、全氮质量分数显著影响土壤微生物的数量和酶的活性;土壤微生物数量与土壤酶活性总体相关性显著。

The experiment was conducted to analyze the traits of soil microbes, soil enzymes and their limited factors in an oak- pine forest widely distributed forest type in the middle Qinling Mountains at Huoditang forest zone. The method field sam- piing combined with laboratory analyzing was applied to measure quantities of soil microbes （bacteria, actinomyces and fungi）, activities of soil enzymes （catalase, urease, sucrase and acidity phophatase） and physicochemical indices of soil in different depth. Both the quantities of microbes and the activities of enzymes in soil decrease with the increase of the depth. Bacteria dominated the ratio of 99% in soil microbial community. Contents of soil moisture, organic matter and to- tal nitrogen impact the quantities of microbes and the activities of enzymes significantly. Activities of soil enzymes correlate with the quantities of soil microorganisms.