生态环境学报Issue(3)：423-429,7.
施氮对不同有机碳水平桉树林土壤微生物群落结构和功能的影响
Effects of nitrogen application on soil microbial community composition and function in Eucalyptus plantations with different soil organic carbon levels
摘要
Abstract
Nitrogen and carbon are two important elements influencing soil microbial community composition and function. The impacts of nitrogen application on soil microbial communities are widely studied in plantations, however, their soil organic carbon levels are poorly considered. To explore coupled impacts of carbon and nitrogen on soil microbial communities, soil microbial community composition (indexed by Phospholipid Fatty-acid Analysis, PLFA) and function (indexed by soil extracellular enzyme activities and soil dissolved organic carbon (DOC) content) were analyzed in Eucalyptus plantations with significantly different soil organic contents and three nitrogen application levels (control: 0 kg·hm-2, normal nitrogen level NN: 166.8 kg·hm-2, the double nitrogen level HN:333.7 kg·hm-2). The total PLFAs, the PLFAs of bacteria, fungi, actinomycetes, and the ratios of fungi/bacteria decreased with the increase of nitrogen application. Fatty-acid 16:1ω5c, 18:1ω9c, 18:2ω9c, 16:1ω7c, i17:0 and 10Me18:0 distinguished the soil microbial communities under different nitrogen application treatments. Cellulase and phenol oxidase activities, and soil organic DOC significantly increased with nitrogen application. Soil microbial PLFA, soil extracellular enzyme activity and soil DOC are significantly higher in the sites with high soil organic carbon content than those in the sites with low soil organic carbon content. However, the responses of soil microbial community composition and function to nitrogen application are different in the two sites with different soil organic carbon contents, which are more sensitive in low soil organic carbon sites. While soil microbial community composition and function only changed in the sites with high soil organic carbon content and HN treatment. We conclude that soil organic carbon content can’t be neglected when the effects of nitrogen fertilization on soil microbial communities are analyzed.关键词
施氮/有机碳水平/微生物群落/真菌/细菌/土壤酶/DOCKey words
nitrogen application/soil organic carbon/microbial community/soil extracellular enzyme/DOC分类
农业科技引用本文复制引用
苏丹,张凯,陈法霖,李睿达,郑华..施氮对不同有机碳水平桉树林土壤微生物群落结构和功能的影响[J].生态环境学报,2014,(3):423-429,7.基金项目
国家自然科学基金项目（31170425）；中国科学院知识创新工程重要方向项目 （）
