| Title |
SWAT Direct Runoff and Baseflow Evaluation using Web-based Flow Clustering EI Estimation System |
| Authors |
장원석 ( Won Seok Jang ) ; 문종필 ( Jong Pil Moon ) ; 김남원 ( Nam Won Kim ) ; 유동선 ( Dong Sun Yoo ) ; 금동혁 ( Dong Hyuk Kum ) ; 김의재 ( Ik Jae Kim ) ; 문유리 ( Yuri Mun ) ; 임경재 ( Kyoung Jae Lim ) |
| Keywords |
K-means clustering EI estimation system; Nash-Sutcliffe efficiency coefficient; Soil and Water Assessment Tool; SWAT auto-calibration tool; Web-based flow clustering EI estimation system |
| Abstract |
In order to assess hydrologic and nonpoint source pollutant behaviors in a watershed with Soil and Water Assessment Tool (SWAT) model, the accuracy evaluation of SWAT model should be conducted prior to the application of it to a watershed. When calibrating and validating hydrological components of SWAT model, the Nash-Sutcliffe efficiency coefficient (EI) has been widely used. However, the EI value has been known as it is affected sensitively by big numbers among the range of numbers. In this study, a Web-based flow clustering EI estimation system using K-means clustering algorithm was developed and used for SWAT hydrology evaluation. Even though the EI of total streamflow was high, the EI values of hydrologic components (i.e., direct runoff and baseflow) were not high. Also when the EI values of flow group I and II (i.e., low and high value group) clustered from direct runoff and baseflow were computed, respectively, the EI values of them were much lower with negative EI values for some flow group comparison. The SWAT auto-calibration tool estimated values also showed negative EI values for most flow group I and II of direct runoff and baseflow although EI value of total streamflow was high. The result obtained in this study indicates that the SWAT hydrology component should be calibrated until all four positive EI values for each flow group of direct runoff and baseflow are obtained for better accuracy both in direct runoff and baseflow. |