Research advances on retaining and transformation of N and P and ecological restoration of riparian buffer zone

The riparian buffer zone is one important component of the riparian ecosystem and has effective interception and transformation functions on the non-point agricultural pollutants.This paper reviews the definition and the characteristic of ecological structure of riparian buffer zone,as well as the function of riparian buffer zone,such as the interception functions on nitrogen and phosphorus,and the ecological restoration of degraded riparian buffer zone.Results show that both grass riparian buffer zone and forest riparian buffer zone can effectively control the migration of nitrogen and phosphorus into water.The width of riparian buffer zone,the hydrological characteristics and soil properties of riparian buffer zone,and seasonal change and the human activities all affect the interception efficiency of riparian buffer zone.The ecological restoration of degraded riparian buffer should be strengthened in order to ensure the health of the riparian ecosystem.Based upon current research weaknesses,this paper raised future research directions and proposed that long term field observation and studies should be conducted and appropriate health indicators should be established for evaluating riparian buffer zone so that scientific evidences can be provided for recovering the degraded riparian buffer zone.