氮添加对贝加尔针茅草原土壤活性有机碳和碳库管理指数的影响  

Effects of nitrogen addition on labile soil organic carbon and carbon pool management index of Stipa baicalensis steppe in Inner Mongolia,China

作　　者：刘红梅 张海芳 赵建宁 王慧 秦洁 杨殿林 张乃芹 LIU Hong-mei;ZHANG Hai-fang;ZHAO Jian-ning;WANG Hui;QIN Jie;YANG Dian-lin;ZHANG Nai-qin(Agro-Environmental Protection Institute, Ministry of Agriculture and Rural Affairs, Key Laboratory of Original Agro-Environmental Pollution Prevention and Control, MARA, Tianjin Key Laboratory of Agro-Environment and Agro-Product Safety, Tianjin 300191, China;School of Ecology and Landscape Architecture, Dezhou University, Dezhou 253023, China)

机构地区：[1]农业农村部环境保护科研监测所,农业农村部产地环境污染防控重点实验室,天津市农业环境与农产品安全重点实验室,天津300191 [2]德州学院生态与园林建筑学院,山东德州253023

出　　处：《草业学报》2020年第8期18-26,共9页Acta Prataculturae Sinica

基　　金：国家自然科学基金面上项目(41877343)资助。

摘　　要：以贝加尔针茅草原为研究对象,施氮模拟氮沉降增加,设置N0,N50,N100,N200,N300(0,50,100,200,300 kg N·hm^-2·年^-1)5个氮添加水平,研究不同氮添加水平变化对土壤活性有机碳和碳库管理指数的影响。结果表明,与对照N0相比,N50、N100、N200和N300处理显著提高了土壤易氧化有机碳和可溶性有机碳含量,显著降低了土壤微生物量碳含量。N100处理显著提高了土壤易氧化有机碳和可溶性有机碳的组分比例,显著提高了土壤碳库活度、碳库活度指数和碳库管理指数。N200和N300处理显著降低了土壤易氧化有机碳组分比例,显著降低了土壤碳库活度、碳库活度指数和碳库管理指数。分析结果表明,土壤易氧化有机碳分配比例、可溶性有机碳分配比例、微生物量碳分配比例、碳库活度指数和碳库管理指数之间呈极显著相关性(P<0.01)。在未来氮沉降持续增加的情况下,贝加尔针茅草原土壤碳库质量可能会降低。The objective of this study was to examine the effects of nitrogen(N)application on labile organic carbon and carbon pool management index of the Stipa baicalensis steppe in Inner Mongolia,China.The treatments in the manipulative experiment included N additions at rates of 0(control),50,100,200 and 300 kg N·ha^-1·yr^-1(designated N0,N50,N100,N200 and N300,respectively).It was found that,compared to N0,the N50,N100,N200 and N300 treatments significantly increased the contents of readily oxidized soil organic carbon and dissolved organic carbon,while decreasing the content of microbial biomass carbon.The N100 treatment significantly increased the proportion of readily oxidized organic carbon and the proportion of dissolved organic carbon,and significantly increased the soil carbon activity,carbon pool activity index and carbon pool management index.The N200 and N300 treatments significantly decreased the proportion of readily oxidized organic carbon,and significantly decreased the soil carbon activity,carbon pool activity index and carbon pool management index.A correlation analysis indicated that there was a significant positive correlation between the proportion of readily oxidized organic carbon,the proportion of dissolved organic carbon,the proportion of microbial biomass carbon,the carbon pool index and the carbon pool management index.Chronic increase in N deposition may reduce the quality of the carbon pool in the S.baicalensis steppe.

关 键 词：贝加尔针茅草原 氮添加 土壤 活性有机碳 碳库管理指数 

分 类 号：S81[农业科学—畜牧学]