• 한국환경과학회지
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• 제7권5호
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• pp.581-590
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• 1998

This st at the development of the adequate sediment yield formulas in Wi-Stream basin ; IHP representative basin in Korea. As a result of applying outstanding sediment yield formulas among the existing formulas, it is analyzed that including the Engelund ＆ Hansen formula, Yang formula is proper to the Wi-Stream basin. And as a result of sensitivity analysis to the sediment parameters it is analyzed that Rijn and Actors ＆ White formula is more sensible than any other formulas which has been applied the velocity and depth among the parameters. Also, Engelund ＆ Hansen and Yang formula is less sensible than any other formulas. In Wi-Stream basin, it is analyzed that Yang and Engelund ＆ Hansen formula is the most suitable sediment yield formula in this study. But because the existing formulas had been developed in foreign countries and applied the foreign natural livers and reservoirs, it makes careful use of Korean alluvial river and hoped that it will be developed the most adequate formula in Wi-Stream basin.

• 한국환경과학회지
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• 제6권5호
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• pp.417-423
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• 1997

The objective of this study Is to supply basic data for large reservoir sedimentation research In future and make suggestions to maintain and opera능 the reservoir more of efficiently. At first, previous studios about the estimation of sediment yield rate were reviewed in Korea. And the discharge rating curves of upstream stage gauging stations and the correlation between dam Inflow and stage discharge were analyzed. With the analysis results, the spec유c sediment rate of Soyanggang dam was estimated as 608 m3/km2/yr. It was similar to that of Soyanggang dam feasibility study and 1994's field surveys of the reservoir than that of 1983's field surveys. Because the sediment rating curves were derived under the low discharge conditions, It needs to be checked under the flood conditions. However, the suggested methods such as flowrate analysis and sediment estimation will be useful to the sediment studios In future. Key words . reservoir sediment, sediment yield rate, rating curve, flowrate analysis.

• 한국환경복원기술학회지
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• 제10권1호
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• pp.36-43
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• 2007

This study was carried out to know how erosion control function of forests varies as forests develop in watersheds. The erosion control function among the forest welfare functions can be estimated by comparing sediment yield in stocked with non-stocked area. Sediment yield of reservoirs in stocked area were collected from farmland improvement associations. The sediment yields in non-stocked area were using USLE (Universal Soil Loss Equation) in the same reservoirs. Forests' erosion control function estimated by differences of the sediment yield between stocked and non-stocked area was static model because of no consideration on forest aging. Dynamic model was developed to consider a forest stand age. The model comprises the relationship between average forest age in watershed and sediment yield. The amount of sediment yield was different depending mother rocks. It decreased exponentially according to the forest's grow up. In case of igneous rock, the volume of sediment yield $Y_{ig}=1.4431e\;^{0.023x}$(x=average forest age), metamorphic rock $Y_{me}=4.7115e\;^{0.0694x}$, and sedimentary rock $Y_{se}=1.2808e\;^{0.028x}$.

• 한국농공학회논문집
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• 제52권6호
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• pp.39-48
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• 2010

Sediment yields from Imha watershed were simulated during 1993-2008 using Hydrologic Simulation Program-Fortran (HSPF). Using observed daily stream flow for 2004-2008 and hourly suspended solid concentration for three events during 2006, HSPF was calibrated and validated at the sites of Imha and Youngyang for stream flow and Dongchun and Jangpachun for sediment yield. The calibration and validation results represented high model efficiency for simulating daily stream flow and hourly suspended solid. The determination coefficients of calibration and validation were 0.90 and 0.81 for daily stream flow, and 0.91 and 0.86 for monthly stream flow, respectively. Based on model tolerances for calibration and validation of stream flow, HSPF performance for simulating stream flow represented 'very good'. The determination coefficients of calibration and validation were 0.94-0.96 and 0.95 for hourly sediment yields, respectively. The average yearly sediment yield during 1993-2008 was 122,290 ton/year and most of sediment yield (77 % of total yield) were generated from June to August. The calibrated HSPF simulated well the movement of water and eroded soil within Imha watershed.

• Spatial Information Research
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• 제13권1호
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• pp.79-90
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• 2005

본 연구는 고랭지 경작지로부터 발생하는 토양유실을 정량적으로 추정하는 것을 목적으로 한다. 강원도 내린천 유역을 대상으로 고랭지 경작지에서 발생하는 연간토양 유실량과 이 토양유실량 중 하천에 도달하는 양을 나타내는 유사량을 추정하였다. 연간토양유실량은 RUSLE 공식을 이용하여 추정하였으며, 유사량은 SEDD 모형을 이용하여 산정하였다. 연구결과 대상지역의 $2.6\%$ 면적을 차지하고 있는 밭이 연간 유역 내에서 발생하는 총토양유실량과 유사량에 대하여 각각 $10.9\%$ 및 $33.12\%$의 비율을 차지하고 있는 것으로 나타났다 또한 고도 400m 이상에 해당하는 고랭지 경작지의 경우 유역 내에서 총 $1.74\%$의 면적을 차지하고 있으나, 연간 총 토양유실량과 유사량에 대해서는 면적에 비하여 월등히 큰 $7.69\%$와 $15\%$의 기여를 하고 있는 것으로 분석되었다. 이상의 결과로부터 내린천 유역의 밭 경작지 특히, 고랭지 경작지에서의 토양유실과 유사량 발생이 다른 토지용도에 비하여 매우 심하게 나타나고 있음을 확인할 수 있었다. 따라서 고랭지 경자지로부터의 토양유실 방지대책이 시급히 마련되어야 할 것으로 생각된다.

• 자원환경지질
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• 제40권1호
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• pp.103-113
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• 2007

GIS와 연계시켜 만든 분산형 모델의 대표적인 경험식인 USLE model과 물리학기반의 GeoWEPP model을 경기도 이천시에 위치한 소유역에 적용하여 2004년 1월에서 2005년 1월까지 1년간의 토사유출량을 비교하였다. 연구기간동안의 유출된 토사량은 실제관측결과 270.54 ton, USLE 모델 적용 시 358.1 ton, 그리고 GeoWEPP 모델 적용 시 283.30 ton으로 각각 산출되었다. 각각의 모델을 적용한 산출량은 실제 산출량보다 과대하게 산출되었으며, 산출결과만을 볼 때, GeoWEPP 모델을 적용한 토사유출량이 USLE 적용 산출량 보다 관측량에 더 근사한 산출량을 보였다. 모델 적용 산출량이 과대산출 된 원인으로는 실험웨어를 월류하여 빠져나간 부유물에 대한 양이 포함되지 않았기 때문으로 판단된다.

• 한국수자원학회논문집
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• 제34권3호
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• pp.199-207
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• 2001

개발에 의하여 증가된 토사유출량의 유역외 배출을 최소화하기 위한 침사지 등의 설계에 필요한 검증된 토사유출량 산정기법이 국내에는 없는 실정이다. 따라서 본 연구에서는 현재까지 개발된 각종 장·단시간 호우에 대한 외국의 토사유출량 산정 기법들 중 개정범용토양손실공식(RUSLE)의 국내 적용 가능성을 검토하였다. 전국 7개 개발현장에서 실측한 강우 및 토사유출량 자료를 RUSLE공식에 적용, 그 적용범위 및 한계성 등을 검토한 결과 국내 개발지역에 대한 토사생산량 산정기법으로써의 가능성을 확인하였으며 RUSLE공식의 적용시 우리나라에서 많이 범하고 있는 각 인자별 산정 오류에 대해서도 검토하였다. RUSLE공식 적용시 필요한 토사전달률에 대해서도 우리나라에 적합한 두 가지 기법을 제시하였다.

• 한국환경과학회지
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• 제22권5호
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• pp.599-608
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• 2013

Jeju island, which is located along the moving path of typhoon, suffers from flooding and overflow by torrential rain. So abrupt runoff occurring, damages of downstream farm field and shore culturing farms are increasing. In this study, Oaedo stream, one of the mountainous streams on Jeju island, was selected as the basin of study subject and was classified into 3 sub-basins, and after the characteristics of subject basin, the soil erosion amount and the sediment delivery of the stream by land usage distribution were estimated with the use of SATEEC ArcView GIS, the sediment yield amount of 2000 and 2005 was analyzed comparatively. As a result of estimating the sediment yield amount of 2000, the three sub-basins were respectively 12,572.7, 14,080 and 157,761 tons/year. and sediment yield amounts were estimated as 35,172.9, 5,266 and 258,535 tons/year respectively in 2005. The soil erosion and sediment yield amount of 2005 using single storm rainfall were estimated high compared with 2000, but for sub-basin 2, the values rather decreased due to changes in land use, and the land coverage of 2005, since there are many classifications of land usage compared with 2000, enabling to reflect more accurate land usage condition, could deduce appropriate results. It is anticipated that such study results can be utilized as basic data to propose a direction to predict the amount of sediment yield that causes secondary flooding damage and deteriorates water quality within detention pond and grit chamber, and take action against damages in the downstream farm field and shore culturing farms.

• 농업과학연구
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• 제47권4호
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• pp.803-814
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• 2020

Managing erosion control dams requires the annual average sediment yield to determine their storage capacity and time to full sediment-fill and dredging. The GeoWEPP (Geo-spatial interface for Water Erosion Prediction Project) model can predict the annual average sediment yield from various land uses and vegetation covers at a watershed scale. This study assessed the GeoWEPP to determine the annual average sediment yield for managing erosion control dams by applying it to five erosion control dams and comparing the results with field observations using ground-based LiDAR (light detection and ranging). The modeling results showed some differences with the observed sediment yields. Therefore, GeoWEPP is not recommended to determine the annual average sediment yield for erosion control dams. Moreover, when using the GeoWEPP, the following is recommended :1) use the US WEPP climate files with similar latitude, elevation and precipitation modified with monthly average climate data in Korea and 2) use soil files based on forest soil maps in Korea. These methods resulted in GeoWEPP predictions and field observations of 0 and 63.3 Mg·yr-1 for the Gangneung, 142.3 and 331.2 Mg·yr-1 for the Bonghwa landslide, 102.0 and 107.8 Mg·yr-1 for the Bonghwa control, 294.7 and 115.0 Mg·yr-1 for the Chilgok forest fire, and 0 and 15.0 Mg·yr-1 for the Chilgok control watersheds. Application of the GeoWEPP in Korea requires 1) building a climate database fit for the WEPP using the meteorological data from Korea and 2) performing further studies on soil and streamside erosion to determine accurate parameter values for Korea.

• 대한토목학회논문집
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• 제35권1호
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• pp.111-117
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• 2015

본 연구에서는 강우의 공간분포에 따른 토사유출의 특성을 토조 실험을 통해 탐구하였다. 강우의 공간분포는 강우 집중위치를 사면의 중앙부와 상류부로 각각 설정함으로 조정하였다. 토사유출의 시간적 변동성을 충분히 포착하기 위해 장시간(8 시간)의 실험시간 동안 높은 시간해상도(10 분)로 직접유출량, 지하수유출량, 토사유출량을 측정하였다. 그 결과, 강우를 토조의 상류부에 위치시킬수록 토사유출량곡선의 첨둣값은 감소하고 누적토사유출량은 증가하였다. 누적토사유출량은 시간에 따라 선형적으로 증가하였으나, 그 증가율이 2 시간을 기준으로 급격히 감소하였다. 이러한 점은 현재 총량 위주로 기록되어있는 토사유출 실측자료를 사용함에 있어 고려해야 할 사항이라고 결론지을 수 있다. 본 연구 결과는 또한, 향후의 토사유출량 실측은 높은 시간해상도로 측정될 필요가 있음을 시사한다.