【摘要】 流域氮污染问题是世界面临的共同难题,大型水利水电工程极大地改变了流域氮循环过程。三峡水库作为我国重要的优质淡水资源库,却面临着支流水华频繁暴发的水安全问题。如何有效削减氮污染并维持水库消落带生态系统的稳定性,是三峡水库生态安全运行中亟待解决的实际问题。水库消落带作为邻近水体的“生物地球化学循环热区”,在营养元素循环、面源污染截留、温室气体排放等过程中扮演着重要角色。随着生物信息学、分子生物学等新型研究手段在环境研究中广泛应用,氮循环过程与机理得到了更微观的诠释,氮循环功能微生物的多样性和生态位分化等方面的研究也取得了突出成果。本文基于对三峡水库消落带土壤-植物-微生物作用下的氮循环关键过程所开展的最新研究,结合消落带水陆交错的特殊环境条件,综述水库消落带中氮循环的关键过程和机理,分析水库消落带对流域水环境和温室气体排放的潜在影响,并对未来消落带亟待解决的问题做了进一步展望,以期为大型水库消落带生态系统的综合管理提供科学支撑。更多还原

【Abstract】 Nitrogen pollution in watersheds is a serious problem all over the world.Large hydropower projects have greatly altered the nitrogen cycle in watersheds.The water in Three Gorges Reservoir,as our national precious freshwater resources,is facing safety issues caused by frequent outbreaks of algal blooms in tributaries.How to reduce nitrogen pollution effectively and maintain the stability of the water-level-fluctuation zone(WLFZ) is a practical issue to be solved urgently,especially to achieve the ecological operation of the Three Gorges Reservoir.As the "biogeochemical cycle hotspot" of the adjacent basin,the reservoir WLFZ plays an important role in the process of nutrient cycling,non-point source pollution interception,and greenhouse gas emissions.With the wide application of new research techniques,such as bioinformatics and molecular biology in environmental research,the process and mechanism of nitrogen cycle have been interpreted more microcosmically,and the research on the diversity and niche divergence of nitrogen cycle functional microorganisms has also made great achievements.Our study is based on the latest research progress of nitrogen cycle process,related soil-plant-microorganism interactions in the land-water ecotones.In addition,this review has summarized the process and mechanism of nitrogen cycle in the reservoir WLFZ,analyzed the potential impact of the reservoir WLFZ on the water environment and greenhouse gas emissions.In order to provide scientific supports for the integrated management on WLFZ ecosystem of large reservoirs,we made a further outlook on the problems to be solved in the future.更多还原