• Journal of Korea Water Resources Association
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• v.44 no.8
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• pp.619-628
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• 2011

The purpose of this study is to evaluate the existing method of calculating rainfall-runoff erosivity using monthly precipitation, such as Fournier's index, modified Fournier's index, IAS (Institute of Agricultural Sciences) index, etc., and to present more reasonable regression model based on monthly rainfall data in Korea. This study introduced a new simplified method of calculating rainfall-runoff erosivity based on monthly precipitation, called by modified IAS index. It was expanded form IAS index which is the simple calculation method by summing up the rainfall amount of two months with maximum amount. Monthly precipitation and annual rainfall-runoff erosivity at 21 weather stations for over 25 years were used to analyze correlation relationship and regression model. The result shows that modified IAS index is the more reasonable parameter for estimating rainfall-runoff erosivity of the middle-western and south-western regions in Korea.

• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.430-430
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• 2022

20년 이상의 분단위 강우자료가 없는 지역에서는 연강수량, 월강수량, 일강수량 등을 이용하여 강우가식성지표를 추정하는 연구가 이루어지고 있다. 이중에서 월강수량을 이용한 연평균 강우가식성지표 추정방법은 Fouriner Index, Modified Index, IAS index, Modified IAS index 등 학계에서 다양한 모델이 제시된 바 있다. 국내에서는 1971 ~ 1999년 기간의 기상청 관측지점에 대한 평가가 일부 이루어진 바 있으나, 월강수량을 이용한 추정모델에 대한 후속 연구는 이루어지지 않았다. 본 연구에서는 1981 ~ 2020년 기간의 기상청 강우자료를 이용하여 월강수량 기반 강우가식성지표 추정모델의 적용성을 평가하기 위한 것으로, 선행 연구에서 기산정된 지점별 연평균 강우가식성지표 값을 바탕으로, 월강수량 기반의 기존 추정모델로 산정한 값을 비교 분석하였다. 이를 바탕으로 실무에서 활용할 수 있도록 월강수량을 이용하여 연평균 강우가식성지표를 추정할 수 있는 경험식을 업데이트 하여 제안하였다.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.6
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• pp.1004-1009
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• 2011

Soil erosion in North Korea has been continued to accelerate by deterioration of topographical conditions. However, few studies have been conducted to predict the amount of soil loss in North Korea due to limited data so far. Rainfall erosivity is an important factor to predict the amount of long-term annual soil loss by USLE (universal soil loss equation). The purpose of this study is to investigate rainfall erosivity, which presented the potential risk of soil erosion by water, in North Korea. Annual rainfall erosivities for 27 stations in North Korea for 1983~2010 were calculated using regression models based on modified Institute of Agricultural Sciences (IAS) index in this study. The result showed that annual average rainfall erosivity in North Korea ranged from 2,249 to 7,526 and averaged value was $4,947MJmm\;ha^{-1}\;hr^{-1}\;yr^{-1}$, which corresponded to about 70% of annual average rainfall erosivity in South Korea. The finding was that the potential risk of soil erosion in North Korea has been accelerated by the increase of rainfall erosivity since the late 1990s.