Driving mechanisms of nitrogen transport and transformation in lacustrine wetlands  

作　　者：ZHAO Shan ZHOU Nian Qing SHEN Xin Ping 

机构地区：[1]Department of Hydraulic Engineering, Tongji University,Key Laboratory of Yangtze River Water Environment, Ministry of Education, Shanghai 200092, China [2]School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, USA [3]Dongting Lake Water Resources Administration Bureau of Hunan Province, Changsha 410007, China

出　　处：《Science China Earth Sciences》2016年第3期464-476,共13页中国科学（地球科学英文版）

基　　金：the National Natural Science Foundation of China (Grant No. 41272249);Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20110072110020)

摘　　要：As an essential component of proteins and genetic material for all organisms, nitrogen(N) is one of the major limiting factors that control the dynamics, biodiversity and functioning of lacustrine wetlands, in which intensified N biogeochemical activities take place. Reactive N loaded into wetland ecosystems has been doubled due to various human activities, including industrial, agricultural activities and urbanization. The main driving mechanisms of N transport and transformation in lacustrine wetlands are categorized to pushing forces and pulling forces in this study. Geomorphology, wetland age, N concentrations, and temperature are the main pushing forces(passive forces); whereas water table variation, oxygen concentration, other elements availability, oxidation-reduction potential(Eh) and p H, and microorganisms are the predominant pulling forces(active forces). The direction and kinetic energy of reactions are determined by pulling forces and then are stimulated by pushing forces. These two types of forces are analyzed and discussed separately. Based on the analysis of driving mechanisms, possible solutions to wetland N pollutions are proposed at individual, regional and global scales, respectively. Additional research needs are addressed to obtain a thorough understanding of N transport and transformations in wetlands and to reduce detrimental impacts of excessive N on such fragile ecosystems.As an essential component of proteins and genetic material for all organisms, nitrogen（N） is one of the major limiting factors that control the dynamics, biodiversity and functioning of lacustrine wetlands, in which intensified N biogeochemical activities take place. Reactive N loaded into wetland ecosystems has been doubled due to various human activities, including industrial, agricultural activities and urbanization. The main driving mechanisms of N transport and transformation in lacustrine wetlands are categorized to pushing forces and pulling forces in this study. Geomorphology, wetland age, N concentrations, and temperature are the main pushing forces（passive forces）; whereas water table variation, oxygen concentration, other elements availability, oxidation-reduction potential（Eh） and p H, and microorganisms are the predominant pulling forces（active forces）. The direction and kinetic energy of reactions are determined by pulling forces and then are stimulated by pushing forces. These two types of forces are analyzed and discussed separately. Based on the analysis of driving mechanisms, possible solutions to wetland N pollutions are proposed at individual, regional and global scales, respectively. Additional research needs are addressed to obtain a thorough understanding of N transport and transformations in wetlands and to reduce detrimental impacts of excessive N on such fragile ecosystems.

关 键 词：Nitrogen Driving mechanisms Transport and transformation Excessive loading Lacustrine wetlands 

分 类 号：X171[环境科学与工程—环境科学]