Analysis of Pollutant load Reduction Efficiency with Riparian Buffer System Using the SWAT-REMM

Abstract

Pollutant in watersheds comes from two major sources which are NPS (nonpoint source pollution) and PS (point source pollution). Most of the pollutant can be treated by wastewater treatment plants. However, wastewater treatment plants may not be an appropriate practice to improve water quality for the watersheds with large portion of NPS pollutant and NPS pollution from direct runoff and baseflow has different characteristics. Therefore the practices to improve water quality need to be comprehensive for pollutants by both direct runoff and baseflow. Riparian buffer, one of practices to manage pollutant in watershed, has been applied to reduce pollutant not only from direct runoff but also baseflow. In this study, the scenarios for pollutant reduction by wastewater treat plants and the nitrogen reduction by riparian buffer were simulated using SWAT-REMM to suggest an effective plan for pollutant reduction from baseflow. Riparian buffer provided nitrogen reduction of 0.2~75.0% in YbB watershed and 38.0~47.0% in GbA watershed. The result indicates that riparian buffer is effective to reduce the pollutant especially from baseflow, and it suggested as suitable for the a watershed which WWTP discharge is not capable to reduce enough pollutant.

Analysis of Environmental Purification Effect of Riparian Forest with Poplar Trees for Ecological Watershed Management: A Case Study in the Floodplain of the Dam Reservoir in Korea

“…In order to analyze the purification effect of riparian forests, long-term monitoring data before and after planting are required, but because field measurements are often impossible, the effect is predicted through modeling [20]. The physical, chemical, and biological processes and outcome prediction of riparian forests can be modeled using the SWAT-REMM (Soil and Water Assessment Tool-Riparian Ecosystem Management Model) model [21][22][23][24]. This model can be used to simulate and predict the effects of riparian forests.…”

“…It is also a study that simulates the effect of improving water quality expected when planting riparian forests throughout a specific watershed, and there is a limitation in considering land use, topography, climate, and pollution source characteristics of a wide range of watersheds. Moreover, there is considerable uncertainty inherent in predicted values, not actual values [24]. Recently, many poplars have been planted near rivers and lakes in South Korea for environmental purification purposes.…”