摘要
综述了湿地氮素传输过程的研究进展。湿地氮素传输过程包括物理过程、化学过程和生物过程 ,与土壤、植物的发生、发育紧密联系在一起 ,并形成了空气 -水 -土 -生命系统中物质循环和能量流动的复杂网络。湿地硝态氮的淋失直接威胁着湿地地下水水质安全 ,N2 O源汇转变受土壤和水体等环境因子的制约 ,氨挥发则与水体 p H值密切相关排放。湿地氮素的化学转化过程是矿质养分供给和 N2 O产生的主要机制 ,受环境因子和人类活动干扰的影响 ;动力学模型可用于描述氮素的化学转化过程。湿地植物的吸收和累积以及微生物的分解过程是湿地氮素循环的重要环节。最后分析了当前国内外研究中存在的不足 。
Wetlands are the most active interface for energy exchange and material movement on the earth, since they are the ecotones between waters and inlands. Nitrogen, one of the important components of wetland soils, is an ecological factor of wetland ecosystems that greatly influence the productivities of wetland ecosystems. The present paper aims to provide a critical review on nitrogen movement and transformation in wetland ecosystems. Nitrogen transmission includes physical, chemical and biological processes, which are closely linked to soil formation and plant growth and consists of a complex network with substance cycles and energy flow in these air- water-soil-life systems. It is a considerable threaten for nitrogen leaching to water quality safety of ground water in wetlands. Wetlands act as sink or source of nitrogen, which is controlled by such environmental factors as soil characteristics or water properties. Ammonia volatilization is one path of nitrogen loss and is greatly related to pH values of waters. Nitrogen mineralization, nitrification and denitrification are main chemical transformation processes and related to each other. They are the main mechanisms of mineral nutrients supply and N_2O emissions, which are greatly influenced by the environmental factors and human activities and can be described by kinetics models. Wetland vegetation's uptake and accumulation and microbial decomposition play the important roles in nitrogen cycles of wetlands. Some nitrogen processes in wetlands have been greatly considered in the past studies, but it is necessary to study comprehensively and continuously nitrogen biogeochemical processes in the future. The key research fields are as follows: (1) nitrogen movement and transformation processes in wetlands with different vegetation types; (2) relationships between nitrogen transmission processes and global changes; (3) effects of LUCC on nitrogen biogeochemical processes; (4) processes and mechanisms of wetland hydrology patterns influencing on nitrogen transmission processes; (5) nitrogen retaining and purification mechanisms of wetland soils; (6) biogeochemical processes and ecological effects of nitrogen cycling in plateau wetlands.
出处
《生态学报》
CAS
CSCD
北大核心
2005年第2期326-333,共8页
Acta Ecologica Sinica
基金
国际合作重点资助项目 (2 0 0 1DFDF0 0 0 4)
中国博士后科学基金资助项目 (2 0 0 40 3 5 0 96)~~
关键词
湿地
氮素
物理过程
化学过程
生物过程
wetlands
nitrogen
physical proceed
chemical proceed
biological proceed
