Estimate Suitable Width for Vegetated Buffer Strips in the Riparian Zone

1. Modeling the width and placement of riparian vegetated buffer strips on the Chi-Jai-Wang Stream, Taiwan Importance of controlling agricultural pollution along the Chi-Jia-Wang Stream to protect the habitat of a species of endangered salmon Paper by Lin C.Y., , Lin W.T., Chou W.C., & . (2002). Modeling the width and placement of riparian vegetated buffer strips: A case study on the Chi-Jai-Wang Stream, Taiwan. Journal of Environmental Management. 66(3), 269-280. Presented by Robert R. Willis, Environmental Studies, GEOG 370, 3/01/2010

2. Estimate Suitable Width for Vegetated Buffer Strips in the Riparian Zone • Problem: Wastewater, surface runoff and groundwater flow contribute to problems of pesticides, nutrients and other organic pollutants entering the stream. • Hypothesis: A wider riparian buffer zone is needed to effectively reduce the amount of pollution

3. Topographic Analysis and Pollutant Transport Simulations • Study Area: Wu-Lin Farm located on the Chi-Jia-Wang Stream riverbank, Taiwan • Simulation of pollutant transport: simulated vertical movement of pollutants in soil to estimate safety depth • Safety depth is vertical depth necessary in a riparian zone for a pollutant to change from high concentration to background level

4. Results • Estimated safety depth for Fanarimol is 5.19 m • Fanarimol is the most highly concentrated pollutant tested so its safety depth should be enough for all other pollutants • Width of vegetated buffer strip can be obtained by using the safety depth

10. Conclusion • When evaluating the total effects of a riparian vegetated buffer strip, the entire watershed area should be considered as a unit • Riparian zones based on a safety depth of 5.9 m are sufficient for this area • Criticisms: Results are only from simulation and more accurate results require onsite data verification