微生物活性对紫色土坡耕地硝酸盐淋失的影响

项目名称： 微生物活性对紫色土坡耕地硝酸盐淋失的影响

项目编号： No.41301266

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 天文学、地球科学

项目作者： 董志新

作者单位： 中国科学院水利部成都山地灾害与环境研究所

项目金额： 26万元

中文摘要： 紫色土坡耕地氮肥投入高，利用率低，硝酸盐淋失问题突出，但以往研究多集中在硝酸盐淋失路径、通量、估算模型等方面，影响紫色土硝酸盐形成和转化的微生物活性并不清楚，针对上述问题，利用紫色土坡地lysimeter装置观测紫色土硝酸盐淋失通量，采用15N同位素稀释技术和乙炔抑制培养法分别测定硝化速率、反硝化速率，并结合实时定量PCR、DGGE及高通量测序等现代分子生物学技术，测定氨氧化微生物、反硝化微生物功能基因转录活性，研究紫色土氨氧化及反硝化微生物活性与硝化-反硝化速率的关系，进而阐明其对硝酸盐形成与转化及硝酸盐的淋失的影响，为紫色土坡耕地氮素的有效管理及硝酸盐淋失的减控提供科学依据。

中文关键词： 紫色土；氨氧化细菌；氨氧化古菌；反硝化细菌；动态监测

英文摘要： Sloping croplands of purple soil widely distributed in the upper Yangtze River play an important role in the local agriculture. A large amount of nitrate loss from hillslope agriculture in the purple soil areas due to low utilization efficiency of fertilizer and heavy soil and water erosion, thus, pose a severe threat to the water quality of the Yangtze River. Previous studies mostly concentrated on paths, flux and models of nitrate leaching, but how microbial activity affects nitrate formation and transformation is not clear. So we proposed to conduct research on transcription activity of amoA, narG and napA , nitrification rate and denitrification rate, and nitrate leaching and try to figure out the relationship among them. In this research, fux of nitrate leaching will be monitored and sampled in the hillslope free-drain lysimeters, rates of nitrification and denitrification are determined using 15N pool dilution technique and acetylene block method respectively, and some modern molecular biology technique including quantitative real-time PCR,DGGE and high-throughput sequencing technique are employed to examine microbial transcription activity. Impact of amnonia-oxidizing microbes and denitrifier on rate of nitrification and denitrification will be analyzed, then relationship between microbial activity and ni

英文关键词： Purple soil；AOB；AOA；Denitrifier；Temporal observation