PROGRESS IN GEOGRAPHY ›› 2009, Vol. 28 ›› Issue (5): 825-832.doi: 10.11820/dlkxjz.2009.05.022

• Original Articles • Previous Articles    

Progress on the Study of Water Purification Ability of Natural Wetlands

YAO Xin1,2,3, YANG Guishan1,3   

  1. 1.Nanjing Institute of Geography and Limnology, CAS, Nanjing 210008, China|
     2. Graduate University of Chinese Academy of Sciences, Beijing 100049|China;  3. State Key Laboratory of Lake Science
     and Environment,Nanjing Institute of Geography and Limnology, CAS, Nanjing 210008, China
  • Online:2009-09-25 Published:2009-09-25


As the kidney of the earth, natural wetlands play an important role in water purification, and guarantee a healthy drinking water supply for rural areas. As a result, utilizing natural wetlands for mitigating non-point source water pollution has attracted more and more worldwide attention in the past decades. The mechanisms of the retention of nitrogen and phosphorus, both of which are considered substantial to water eutrophication, are mainly due to the cooperative functions of wetland sediment, plants and microbes. The detailed processes of pollutant removal involve sedimentation, dissolution, biological adsorption, and biochemical reactions mediated by microbes, such as nitrification, denitrification, etc. The water purifying efficiencies of natural wetlands have great differences between each other, by reason of the different wetland characteristics, which include wetland area, wetland spatial structure, wetland location, loading time of water purifying, precipitation and temperature, etc. However, results drawn by different scientists  from research work at different wetlands varied between each other. Natural wetlands have many types, three of which, named riparian wetlands, river wetlands and peatlands, have been most widely used in water purification. The reason is that: first, they are the most widely distributed wetlands around the world; second, they satisfied the demand for socio-economic development. Each type of the three had respective research progress in both mechanisms and applications of pollutant removal, and the progress in one type usually differed quite a lot from that of the others, as a result of different research histories and varied characteristics of sub-disciplines.
The potential aspects to be attached importance in the future of the research on natural wetland purification ability are as follows: the physical and chemical processes in wetlands boundary and their impacts on water purification ability; restoration of degraded wetlands and the recovery of their water purification ability; continuable programming of wetland water purifying on catchment scale; and dynamic impacts of wetland changes driven by natural and human factors.

Key words: natural wetlands;water purification;wetland type