Prediction of Soil Loss and Runoff with Precipitation Change On From Sloped Upland in Korea.

Major impacts of climate change expect that soil erosion rate may increase during the 21^st century. This study was conducted to apply and adjust CLIGEN parameter values to generate realistic precipitation change scenarios and assess the future potential impacts of precipitation change on soil erosion at upland soils of highland in Korea. The investigated area, DaeGwalLyeong Gang-won province located on 800 m sea-level highland which was a representative highland agriculture in Korea. This area produced vegetables such as chinese cabbage and radish adapted by cool temperature, long solar radiation and plenty rainfall in summer. For computation of soil loss, WEPP (Water Erosion Prediction Project) model was used. The changes of precipitation for 2010 to 2090s were predicted under A1B scenarios made by National Institute of Meteorological Research in Korea. As results, the predicted precipitations were increased by 6.7% for 2010 to 2030s, 9.5% for 2040 to 2060s and 19.0% for 2070 to 2090s, respectively. After model calibration and validation using 3 year (2005-2007) observed lysimeter data, the soil loss changes estimated with WEPP as a result of changes in the frequency of precipitation events were increased by 8% for 2010 to 2030s, 11% for 2040 to 2060s and 23% for 2070 to 2090s, respectively. Overall, these results were emphasized the significance of precipitation. However, it should be noted that when precipitation becomes insignificant, the results may turn out to be complex due to the large interaction among plant biomass, runoff and erosion.