LITERATURE REVIEW ON BUFFER POLLUTANT REMOVAL

Yu, D.

A riparian buffer (also known as riparian vegetative filter strips, or buffer strips) is an area of vegetated land surrounding a waterbody, potentially capable of filtering non-point source pollution in runoff from adjacent lands. Main pollutants studied include sediment, nitrogen, phosphorus, bacteria, and pesticides. Although the literature suggests a general consensus about a riparian buffer’s ability to filter pollutants, efficiencies of removal have varied greatly for certain pollutants. Therefore, it is important to review current literature in order to determine the reasons for such a large range of removal rates. This review was carried out with emphasis on the quantitative results of pollutant reduction as well as the methods of experimentation used to test riparian buffer efficiencies. Depending on the pollutant in question, resulting data fluctuates from study to study, and is discussed further on; however, in terms of the latter, the majority of studies examined used plot or soil boxes under monitored amounts of runoff and applied pollutants. While this method provides insightful data on a riparian buffer’s filtration capability, only a few papers were found regarding the resulting effects on water quality of the waterbody that the riparian buffer is protecting. This is especially important in lakes and ponds where renewal of water is relatively low. The studies that observed the effect of riparian buffers on a watershed scale focused mainly on nitrogen and phosphorus levels due to agricultural practices. Watershed level pollutant removal studies are examined separately in order to compare and contrast their methodology for further research projects. They are discussed after analysis of pollutant removal in plot and field test.