• 산업기술연구
• /
• 제19권
• /
• pp.147-154
• /
• 1999

The soil loss by rainfalls or runoffs has been one of the main environment problems in 20th century. The soil loss cause the various problems those are decreasing of the agricultural productivity, desolating of pasture land and disturbing of water flowing. Therefore, it is very important to measure properly various factors those are affecting to soil loss and to recognize a seriousness of soil loss problem. In this study, we use the USLE(Universal Soil Loss Equation) as a basic approaching way for soil loss analysis in a watershed, and the GSIS(Geo-Spatial Information System) technique is applied to evaluate for factors those are related to the USLE. The results of this study are consisted of three parts those are to build up the various topographical information that is needed for analysis of wide area soil loss by using the USLE, to evaluate the factors those are needed to the USLE, to estimate the soil loss condition of subbasin in the watershed.

• 대한공간정보학회지
• /
• 제15권3호
• /
• pp.77-85
• /
• 2007

토양침식의 산정은 많은 비용과 시간을 요구한다. 한 지역에서 토양침식을 예측하기 위한 많은 모형들이 있지만, 범용토양손실공식(USLE, Universal Soil Loss Equation)이 연 토양 침식량 산정을 위한 경험식으로 가장 널리 사용되고 있다. 토양침식은 강우강도, 토양의 종류, 토지 피복과 토지이용, 사면경사와 경사길이, 그리고 토양보전을 위한 시설의 영향을 받는다. 이러한 모든 변수들은 공간적으로 분포되어 있기 때문에 지형정보시스템(GIS)이 토양침식 영향평가에 널리 적용될 수 있다. 본 연구에서는 IHP 대표 유역인 보청천 유역을 대상으로 지형정보시스템(GIS)과 범용토양손실 공식을 연계하여 태풍 루사의 강우에 의한 유역에서의 토양 침식량을 산정하였다.

• 한국농공학회논문집
• /
• 제65권3호
• /
• pp.29-42
• /
• 2023

Universal Soil Loss Equation (USLE) is suggested and employed in the policy to conserve soil resources and to manage the impact of development, since soil loss is very essential to nonpoint source pollution management. The equation requires only five factors to estimate average annual potential soil loss, USLE is simplicity provides benefits in use of the equation. However, it is also limitation of the model, since the estimated results are very sensitive to the five factors. There is a need to examine the application procedures. Three approaches to estimate potential soil loss were examined, In the first approach, all factors were prepared with raster data, soil loss were computed for each cell, and sum of all cell values was determined as soil loss for the watersheds. In the second approach, the mean values for each factor were defined as representing USLE factors, and then the five factors were multiplied to determine soil loss for the watersheds. The third approach was same as the second approach, except that the Vegetative and Mechanical measure was used instead of the Cover and management factor and Support practice factor. The approaches were applied in 38 watersheds, they displayed significant difference, moreover no trends were detected for the soil loss at watersheds with the approaches. Therefore, it was concluded that there is a need to be developed and provided a typical guideline or public systems so that soil loss estimations have consistency with the users.

• 한국수자원학회:학술대회논문집
• /
• 한국수자원학회 2001년도 학술발표회 논문집(I)
• /
• pp.409-415
• /
• 2001

• 한국지하수토양환경학회지:지하수토양환경
• /
• 제24권5호
• /
• pp.31-41
• /
• 2019

In 2013, the Ministry of Environment in South Korea promulgated a new regulatory bulletin that contained revised enforcement ordinance on soil management protocols. The bulletin recommends the use of Universal Soil Loss Equation (USLE) for the soil erosion estimation, but USLE has limited applicability in prediction of soil erosion because it does not allow direct estimation of actual mass of soil erosion. Therefore, there is a great need of revising the protocol to allow direct comparison between the measured and estimated values of soil erosion. The Korean Soil Loss Equation (KORSLE) was developed recently and used to estimate soil loss in two fields as an alternative to existing USLE model. KORSLE was applied to estimate monthly rainfall erosivity indices as well as temporal variation in potential soil loss. The estimated potential soil loss by KORSLE was adjusted with correction factor for direct comparison with measured soil erosion. The result was reasonable since Nash-Stucliff efficiency were 0.8020 in calibration and 0.5089 in validation. The results suggest that KORSLE is an appropriate model as an alternative to USLE to predict soil erosion at field scale.

• 한국산림과학회지
• /
• 제83권3호
• /
• pp.322-330
• /
• 1994

토양침식에 영향을 미치는 강우, 토양, 지형, 식생 등을 종합적으로 고려하여 단위면적당 토양유실량(土壤流失量)을 예측하는 범용토양유실식(汎用土壤流失式)(Universal Soil Loss Equation)을 지리정보(地理情報)시스템(GIS)에 접목시켰다. 경기도 광릉 임업연구원 시험림을 연구지역으로 선정하여 이곳에서 지난 12년 동안 측정된 시간별 강우자료를 이용하여 강우인자(强雨因子)(R) 값을 산출하였고, 토양도, 지형도, 위성자료 등을 이용하여 USLE 계산에 필요한 다른 인자들의 값을 $25{\times}25m^2$의 격자마다 입력하여 디지털공간정보 데이터베이스를 구축하였다. 각 격자단위로 USLE에 의하여 토양유실량이 계산된 후 그 결과를 종합하여 토양유실의 정도를 공간적으로 살펴볼 수 있는 디지털지도가 산출되었다. GIS에 의한 USLE의 적용은 일정한 테두리 안의 산림유역(山林流域)에서 발생되는 강우에 의한 토양유실량을 추정할 수 있을 뿐만아니라, 주변지역과 비교하여 토양유실의 위험이 높은 특정지점을 공간적으로 파악할 수 있다는 장점이 있다. 이러한 접근 방법은 임지전용(林地轉用), 임도(林道)개설, 벌채, 산불 및 병충해에 의한 임지의 변화가 토양침식에 미치는 영향을 효과적으로 분석할 수 있는 도구로 사용될 수 있을 것이다.

• 한국조경학회지
• /
• 제24권3호
• /
• pp.115-132
• /
• 1996

The purpose of this study is to estimate the soil loss amount with Geographic Information System according to the land use change of Buju mountain area in Mokpo city. To estimate the soil loss, Universal Soil Loss Equation which is the most proper technique to predict soil loss in this site condition is adopted and IDRISI, a raster GIS software, is used. GIS application with USLE is very efficient to estimate soil loss accurately and fastly. In order to decide value and to find application method of USLE factors, we used existing rainfall erosion index, soil erodibility analysis, slope length, slope steepness, vegetation management and practices, which are rated by GIS through the analysis of various studies related USLE. The result of this study was compared with the previous other researches to verify our method of constructing numerical data of USLE's factors. The result of verification of our way showed significance for the soil loss in forest area. But the result of verification for the soil loss in forest area. But the result of verification for the soil loss of cultivated area showed some errors. It seems that this result was due to local variation of topographical map.

• 한국환경농학회지
• /
• 제27권4호
• /
• pp.314-320
• /
• 2008

During the summer season, more than half of the annual precipitation in Korea occurs during the summer season due to the geographical location in the Asian monsoon belt. So, this causes severe soil erosion from croplands, which is directly linked to the deterioration of crop/land productivity and surface water quality. Therefore, much attention has been given to develop accurate estimation tools of soil erosion. The aim of this study is to assess the performance of using the empirical Universal Soil Loss Equation (USLE) and the physical-based model of the Water Erosion Prediction Project (WEPP) to quantify eroded amount of soil from agricultural fields. Input data files, including climate, soil, slope, and cropping management, were modified to fit into Korean conditions. Chuncheon (forest) and Jeonju (level-plain) were selected as two Korean cities with different topographic characteristics for model analysis. The results of this current study indicated that better soil erosion prediction can be achieved using the WEPP model since it has better power to illustrate a higher degree of spatial variability than USLE in topography, precipitation, soils, and crop management practices. These present findings are expected to contribute to the development of the environmental assessment program as well as the conservation of the agricultural environment in Korea.

• 대한토목학회논문집
• /
• 제26권1D호
• /
• pp.141-147
• /
• 2006

강우에 의해서 발생하는 토양유실은 비옥한 표토를 유실시켜 생산성의 저하를 초래하고, 유실된 토양입자는 하천이나 호수, 댐 등에 퇴적되어 저수용량의 감소와 수질관리에 어려움을 야기 시키므로 이에 대한 대처가 필요하다. 본 연구에서는 위성 영상과 GIS 기법을 활용하여 유역내 토양침식에 영향을 미치는 토양조건, 피복조건, 지형조건들을 추출하고 이 요소들을 범용토양유실공식(USLE; Universal Soil Loss Equation)에 적용하여 유입퇴적량 및 유입 가능성이 높은 위치를 파악하였다. 또한 유입되어 하상에 쌓여 있는 퇴적량은 투과성이 강한 음향측심기를 활용하여 퇴적층과 지층의 고도 정보를 획득하여 산정하고 유실량과 퇴적량을 비교하여 퇴적되는 비율을 도출하였다.

• 한국농공학회논문집
• /
• 제61권6호
• /
• pp.55-65
• /
• 2019

Universal Soil Loss Equation (USLE) is to estimate potential soil loss and has benefit in use with its simplicity. The equation is composed of five factors, one of the factors is the slope length and steepness factor (LS factor) that is for topographic property of fields to estimate potential soil loss. Since the USLE was developed, many equations to compute LS was suggested with field measurement. Nowadays the factor is often computed in GIS software with digital elevation model, however it was reported that the factor is very sensitive to the resolution of digital elevation model. In addition, the digital elevation model of high resolution less than 3 meter is required in small field application, however these inputs are not associate with the empirical models' backgrounds since the empirical models were derived in 22.1 meter field measurements. In the study, four equation to compute LS factor and two approaches to determine slope length and steepness were examined, and correction factor was suggested to provide reasonable precision in LS estimations. The correction factor is computed with field area and cell size of digital elevation model, thus the correction factor can be adapted in any USLE-based models using LS factor at field level.