Korean Journal of Soil Science and Fertilizer ISSN:0367-6315(Print) 2288-2162(Online) 한국토양비료학회 학회지

Sustainable soil environment along with available water resources is critical for food security and agricultural productivity. The Korea territory consists of 65% of mountainous topography and the variability of rainfall is rapidly increasing due to climate change, thereby increasing a risk of soil erosion. Soil erosion by water has been estimated using the empirical equations with accumulated data over the time in the U.S. since 1930 s, representatively the Universal Soil Loss Equation (USLE) published by the U.S. Department of Agriculture (USDA); however, this empirical model is not always well fitted to soil erosion estimations in other countries because of different regional characteristics. Moreover, application of the conventional equations of soil erosion like USLE for estimation of soil erosion under climate change is not appropriate. This study employed the data of rainfall erosivity for past 30 years (1981 - 2010) and recent 10 years (2011 - 2020) observed from ≤60 observations in Korea and compared them to evaluate the effect of climate change on soil erosion in Korea. The relationship between rainfall erosivity and daily maximum precipitation was positive (R² = 0.66), but indicated different central tendencies between data for past 30 years and recent 10 years. The values of rainfall erosivity in the southeast part of the country, e.g., Daegu, Ulsan, and Busan, have increased over the last 10 years compared to those over the past 30 years. The more effective and practical estimation technique of soil erosion should further be developed to ensure the climate change effects in Korea.

Mapping the average annual R factor for each decade.