【摘要】 【目的】研究不同施氮量对土壤微生物群落功能多样性和酶活性的影响。【方法】通过野外大田定位试验,于2009年7月15至2009年9月30采用微生物自动分析系统BIOLOG微平板分析法,对不同施氮水平下土壤微生物群落功能多样性,及水解酶活性的动态变化进行了研究。研究涉及N0(0 kg.hm-2)、N1(60 kg.hm-2)、N2(120 kg.hm-2)和N3(180 kg.hm-2)4个施氮水平。【结果】低氮(N1)、中氮(N2)和高氮(N3)处理的微生物群落碳源利用率(AWCD)、微生物群落Shannon指数(H)和微生物群落丰富度指数(S)均高于零氮(N0)处理,其中N2处理最高。主成分分析表明,不同施氮水平土壤微生物功能多样性差异明显,起分异作用的主要碳源是糖类和氨基酸类。土壤蔗糖酶、脲酶和碱性磷酸酶活性均以N2处理最高,分别为24.85 mg glucose.g-1.(24 h)-1、1.04 mg NH3-N.g-1.(24 h)-1和2.40 mg hydroxybenzene.g-1.(24 h)-1。【结论】氮肥的施用可以提高土壤微生物群落碳源利用率、微生物群落的丰富度和功能多样性。低量和中量氮肥能够提高蔗糖酶和脲酶活性,而中量和高量氮肥可以增加碱性磷酸酶活性。更多还原

【Abstract】 【Objective】The aim of the experiment is to investigate the effects of nitrogen application rates on soil microbial community and enzyme activities in Lou soil.【Method】From July 15 to September 30 in 2009,using microbial analysis system BIOLOG,the soil microbial community and the dynamic change of enzyme activities were analyzed in a short-term experiment carried out in Meixian county.The experiment consists of four nitrogen application rates: N0(0 kg·hm-2),N1(60 kg·hm-2),N2(120 kg·hm-2),and N3(180 kg·hm-2).【Result】Functional diversity of soil microbial community and enzyme activities were analyzed.The results showed that AWCD,Shannon index(H) and Richness index(S) in the N1,N2 and N3 treatments were higher than the N0 treatment,and the N2 treatment was the highest.Principal component analysis demonstrated that there was a significant difference among different N application rates depending on carbohydrates and amino acids.Soil invertase,urease and alkaline phosphatase activities in the N2 treatment was the highest,c.e.24.85 mg glucose·g-1·(24 h)-1,1.04 mg NH3-N·g-1·(24 h)-1 and 2.40 mg hydroxybenzene·g-1·(24 h)-1.【Conclusion】Nitrogen fertilizer application can improve the diversities of soil microbial community,the utilization rate of carbon source,richness of soil microbial community.Low and medium rates of nitrogen fertilizer may improve the activities of invertase and alkalime,while high nitrogen rate can increase phosphatase activities.更多还原