| Title |
Development of a Grid-based Daily Watershed Runoff Model and the Evaluation of Its Applicability |
| Keywords |
grid-based;daily runoff model;MODIS LAI;runoff;soil moisture;evapotranspiration;Penman-Monteith;격자기반;분포형;일유출모형;유출량;토양수분;증발산량 |
| Abstract |
This study is to develop a grid-based daily runoff model considering seasonal vegetation canopy condition. The model simulates the temporal and spatial variation of runoff components (surface, interflow, and baseflow), evapotranspiration (ET) and soil moisture contents of each grid element. The model is composed of three main modules of runoff, ET, and soil moisture. The total runoff was simulated by using soil water storage capacity of the day, and was allocated by introducing recession curves of each runoff component. The ET was calculated by Penman-Monteith method considering MODIS leaf area index (LAI). The daily soil moisture was routed by soil water balance equation. The model was evaluated for 930 ㎢ Yongdam watershed. The model uses 1 km spatial data on land use, soil, boundary, MODIS LAI. The daily weather data was built using IDW method (2000-2008). Model calibration was carried out to compare with the observed streamflow at the watershed outlet. The Nash-Sutcliffe model efficiency was 0.78~0.93. The watershed soil moisture was sensitive to precipitation and soil texture, consequently affected the streamflow, and the evapotranspiration responded to landuse type. |