• 제목/요약/키워드: Erosion.Deposition

검색결과 216건 처리시간 0.035초

안면도 바람아래 할미섬 주변의 시계열적 침식·퇴적환경 변화 분석 (A Time-Series Analysis of the Erosion and Deposition around Halmi-island, Baramarae)

  • 유재진;김장수;장동호
    • 한국지형학회지
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    • 제23권1호
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    • pp.47-60
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    • 2016
  • In this study, datum points measurement have been collected and then weather data have been analyzed to figure out erosion and deposition environmental change around Halmi-island, Baramarae. First of all, it was difficult to analyze geomorphological change which is caused by climate change because of quite short term of collection period of data. However, differences in spatial distribution of erosion and deposition have locally been shown. In all season, the wind is blowing in north and north-west direction mostly except in summer which is shifted to south direction. However, since its ratio which are above 5m/s is much lower than the north and north-west wind, its effect on geomorphological process is very tiny. In order to look at a tendency of erosion and deposition environmental change around Baramarae Halmi-island, the periphery of Halmi-island was classified to east and west part, then accumulated erosion and deposition values have been calculated. As a result, generally, the datum points are located in the west part which are mostly depositional sites. On the other hand, the datum points are located in east part showed the dominant erosion patterns.

식생에 의한 하안 퇴적과 침식 경감 (Deposition and Erosion Relief of Riverfront by Vegetation)

  • 김진홍
    • Ecology and Resilient Infrastructure
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    • 제2권2호
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    • pp.154-160
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    • 2015
  • 본 연구에서는 현지조사를 통해 식생의 하안 퇴적과 침식 경감을 판단하였다. 달뿌리풀은 임계유속 1.0 m/s-1.2 m/s을 기준으로 0.2 m 정도의 하안 퇴적과 0.3 m-0.4 m의 침식 경감 기능을 발휘하였다. 갈대는 임계유속 0.6 m/s-0.7 m/s을 기준으로 0.1 m-0.4 m의 하안 퇴적과 0.2 m-0.3 m의 침식 경감 기능을 발휘하였다. 갯버들은 임계유속 1.2 m/s-1.4 m/s을 기준으로 0.1 m-0.2 m의 하안 퇴적과 0.4 m-0.5 m의 침식 경감 기능을 발휘하였다. 물억새는 임계유속 0.6 m/s-0.7 m/s을 기준으로 0.1 m-0.4 m의 하안 퇴적과 0.1 m-0.2 m의 침식 경감 기능을 나타내었다. 조사 대상 식생 중 갯버들이 가장 높은 하안 침식 경감 기능을, 물억새가 가장 낮은 침식 경감 기능을 발휘하였다. 그러나 현지조사 결과 대상 식물종 모두 하안 퇴적 및 침식 경감 기능을 발휘함으로써 안정하도 형성에 기여함을 알 수 있었다.

지형학적 인자 및 강우량에 따른 침식 및 퇴적의 영향 평가 (Assessment of the Effect of Geographic Factors and Rainfall on Erosion and Deposition)

  • 유완식;이기하;정관수
    • 한국방재학회 논문집
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    • 제11권2호
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    • pp.103-112
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    • 2011
  • 본 연구에서는 분포형 강우-유사-유출 모형을 이용하여 격자기반의 유역침식 및 퇴적 공간분포 정보를 획득하고, 유역의 지형학적, 수문기상학적 특성인자가 유역의 침식 및 퇴적에 미치는 영향을 평가한다. 유역의 지형학적 특성을 대표하는 인자로는 유역면적, 지표흐름 이동거리, 국부경사를 선택하였으며, 격자기반의 누적강우량을 수문기상학적 인자로 활용하여 대상유역에서의 침식 및 퇴적의 변동성을 분석한다. 유역면적에 따른 침식 및 퇴적의 변화양상을 분석하기 위해 대상유역은 Strahler 하천 차수법칙에 의해 다수의 소유역으로 구분되었으며, 면적에 따른 변동성을 분석한 결과, 침식 및 퇴적 모두 면적이 커짐에 따라 선형적으로 증가하는 경향을 보였다. 지표흐름의 이동거리 및 국부경사에 따른 침식 및 퇴적양상의 분석 결과, 침식은 유역전반에 걸쳐 비교적 균등하게 발생하였으나 퇴적의 경우 짧은 지표흐름 이동거리 및 완만한 경사를 갖는 하천선 인접 격자에서 집중적으로 발생하였다. 또한 격자별 누적 강우량에 따른 침식 및 퇴적 변동성 분석결과, 강우량이 증가함에 따라 침식은 점진적으로 증가하는 반면 퇴적은 강우량 증감에 따라 불규칙적인 변동성을 나타내었다. 이상의 결과로부터 본 연구에서 선택된 지형학적 인자들은 퇴적과정에 밀접한 관련이 있으며, 강우량은 유역의 침식에 영향을 미치는 매우 중요한 인자임을 확인하였다.

GRID-BASED SOIL-WATER EROSION AND DEPOSITION MODELING USING GIS AND RS

  • Kim, Seong-Joon
    • Water Engineering Research
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    • 제2권1호
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    • pp.49-61
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    • 2001
  • A grid-based KIneMatic wave soil-water EROsion and deposition Model(KIMEROM) that predicts temporal variation and spatial distribution of sediment transport in a watershed was developed. This model uses ASCII-formatted map data supported from the regular gridded map of GRASS (U.S. Army CERL, 1993)-GIS(Geographic Information Systems), and generates the distributed results by ASCII-formatted map data. For hydrologic process, the kinematic wave equation and Darcy equation were used to simulated surface and subsurface flow, respectively (Kim, 1998; Kim et al., 1998). For soil erosion process, the physically-based soil erosion concept by Rose and Hairsine (1988) was used to simulate soil-water erosion and deposition. The model adopts single overland flowpath algorithm and simulates surface and subsurface water depth, and sediment concentration at each grid element for a given time increment. The model was tested to a 162.3 $\textrm{km}^2$ watershed located in the tideland reclaimed ares of South Korea. After the hydrologic calibration for two storm events in 1999, the results of sediment transport were presented for the same storm events. The results of temporal variation and spatial distribution of overland flow and sediment areas are shown using GRASS.

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플라즈마 디스플레이 패널의 MgO막 부식 특성에 관한 연구 (The Study of erosion characteristics for MgO layer in plasma display panel)

  • 신재화;정동효
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2002년도 학술대회 논문집 전문대학교육위원
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    • pp.72-74
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    • 2002
  • In this paper, we showed the erosion characteristics of MgO protector layer releated to lifetime of plasma display panel(PDP). We observed MgO erosion characteristic as a functions of deposition conditions. In RIE condition of Xe gas, the lowest erosion rate appears in the conditions of no heating, bias voltage -30V and pressure 5mtorr. In general. as deposition rate increases, erosion rate decreases.

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Comparison of soil erosion simulation between empirical and physics-based models

  • Yeon, Min Ho;Kim, Seong Won;Jung, Sung Ho;Lee, Gi Ha
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2020년도 학술발표회
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    • pp.172-172
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    • 2020
  • In recent years, soil erosion has come to be regarded as an essential environmental problem in human life. Soil erosion causes various on- and off-site problems such as ecosystem destruction, decreased agricultural productivity, increased riverbed deposition, and deterioration of water quality in streams. To solve these problems caused by soil erosion, it is necessary to quantify where, when, how much soil erosion occurs. Empirical erosion models such as the Universal Soil Loss Equation (USLE) family models have been widely used to make spatially distributed soil erosion vulnerability maps. Even if the models detect vulnerable sites relatively well by utilizing big data related to climate, geography, geology, land use, etc. within study domains, they do not adequately describe the physical process of soil erosion on the ground surface caused by rainfall or overland flow. In other words, such models remain powerful tools to distinguish erosion-prone areas at the macro scale but physics-based models are necessary to better analyze soil erosion and deposition and eroded particle transport. In this study, the physics-based Surface Soil Erosion Model (SSEM) was upgraded based on field survey information to produce sediment yield at the watershed scale. The modified model (hereafter MoSE) adopted new algorithms on rainfall kinematic energy and surface flow transport capacity to simulate soil erosion more reliably. For model validation, we applied the model to the Doam dam watershed in Gangwon-do and compared the simulation results with the USLE outputs. The results showed that the revised physics-based soil erosion model provided more improved and reliable simulation results than the USLE in terms of the spatial distribution of soil erosion and deposition.

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Impacts of temperature variations on soil organic carbon and respiration at soil erosion and deposition areas

  • Thet Nway Nyein;Dong Kook Woo
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2023년도 학술발표회
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    • pp.447-447
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    • 2023
  • Soil organic carbon (SOC) is a critical indicator of soil fertility. Its importance in maintaining ecological balance has received widespread attention. However, global temperatures have risen by 0.8℃ since the late 1800s due to human-induced greenhouse gas emissions, resulting in severe disruptions in SOC dynamics. To study the impacts of temperature variations on SOC and soil respiration, we used the Soil Carbon and Landscape co-Evolution (SCALE) model, which was capable of estimating the spatial distribution of soil carbon dynamics. The study site was located at Heshan Farm (125°20'10.5"E, 49°00'23.1"N), Nenjiang County in Heilongjiang Province, Northeast China. We validated the model using observed soil organic carbon and soil respiration in 2015 and achieved excellent agreement between observed and modeled variables. Our results showed considerable influences of temperature increases on SOC and soil respiration rates at both erosion and deposition areas. In particular, changes in SOC and soil respiration at the deposition area were greater than at the erosion area. Our study highlights that the impacts of temperature elevations are considerably dependent on soil erosion and deposition processes. Thus, it is important to implement effective soil conservation strategies to maintain soil fertility under global warming.

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하구둑 방류와 환경적 인자에 따른 낙동강 하구 지역 해저 지형변화 연구 (Bathymetric Changes in the Nakdong River Estuary owing to Discharge from the Nakdong River Barrier and Environmental Factors)

  • 김기철;김성보
    • 한국환경과학회지
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    • 제30권7호
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    • pp.507-517
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    • 2021
  • In this study, the bathymetric data acquired from 2018 to 2020 and the precipitation and suspended sediment data were analyzed for changes in bathymetry owing to the discharge from the Nakdong River barrier and environmental factors, especially the torrential rain in 2020. Sediment erosion and deposition processes are repeated because of complex environmental factors such as discharge from the Nakdong River barrier and the influence of waves generated from the external sea. In the first half of the year after the dry season, bathymetric data showed relative erosion trends, whereas in the second half after the flood season, deposition trends were identified owing to the increase in sediment transport. However, the data from the second half of 2020 showed a large amount of erosion, resulting in tendencies different to those of erosion in the first half and deposition in the second half of the year. This result is judged to be influenced by the weather in the summer of 2020. The torrential rain in the summer of 2020 resulted in a higher force of erosion than that of deposition. In summary, the tendency for erosion is more significant than that of sedimentation, especially in the main channel area of the Nakdong River.

SATEEC과 USPED를 이용한 토양 유실량 산정 및 우선관리 유역 선정 평가 (Estimation of Soil Erosion using SATEEC and USPED and Determination of Soil Erosion Hot Spot Watershed)

  • 서일규;박윤식;김남원;문종필;류지철;옥용식;김기성;임경재
    • 한국물환경학회지
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    • 제26권3호
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    • pp.497-506
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    • 2010
  • Severe muddy water problem has been the hot issue in Korea. Because of increased nonpoint source pollutions at Kangwon province, best soil erosion management system is required to reduce inflow of nonpoint source pollutions into the waterbodies. The USLE-based SATEEC system have been developed and enhanced for soil erosion and sediment yield estimation. However, the SATEEC cannot estimate soil depositions depending on topography in the watershed, while the USPED estimates soil erosion and deposition using sediment transport capacity of the surface runoff. In this study, the SATEEC and USPED were used to determine soil erosion hot spot subbasins. For this, 54 subbasins were delineated. In general, soil erosion hot spot subbasins were identified similarly with SATEEC and USPED. However, depending on erosion and deposition patterns in each subbasin. USPED estimated soil erosion hot spot subbasins didn't match those estimated with SATEEC. For some subbasins, much deposition was expected than erosion. This indicates that SATEEC estimated soil erosion values may be overestimated for these subbasins. Thus, care should be taken when understanding soil erosion status in the watershed based on USLE-based SATEEC results. In addition, the USPED results could be used to identify the site-specific soil erosion best management practices. If the USPED and USLE-based SATEEC are combined, it would help determining soil erosion hot spot subwatersheds in economic and environmental perspectives.

Thematic Map Construction of Erosion and Deposition in Rivers Using GIS-based DEM Comparison Technique

  • Han, Seung Hee
    • 한국측량학회지
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    • 제34권2호
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    • pp.153-159
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    • 2016
  • Rivers refer to either natural or artificial structures whose primary functions are flood control and water conservation. Due to recent localized torrential downpours led by climate change, large amounts of eroded soil have been carried away, forming deposits downstream, which in turn degrades the capacity to fulfill these functions. To manage rivers more effectively, we need data on riverbed erosion and deposition. However, environmental factors make it challenging to take measurements in rivers, and data errors tend to prevent researchers from grasping the current state of erosions and deposits. In this context, the aim of the present study is to provide basic data required for river management. To this end, the author made annual measurements with a Real-time Kinematic-Global Positioning System (RTK-GPS) and a total station in Pats Cabin Canyon, Oregon, United States, and also prepared thematic maps of erosion and deposition thickness as well as water depth profiles based on a GIS spatial analysis. Furthermore, the author statistically analyzed the accuracy of three dimensional (3D) measurement points and only used the data that falls within two standard deviations (i.e. ±2σ). In addition, the author determined a threshold for a DEM of Difference (DoD) by installing measurement points in the rivers and taking measurements, and then estimated erosion and deposition thickness within a confidence interval of ±0.1m. Based on the results, the author established reliable data on river depth profiles and thematic maps of erosion and deposition thickness using pre-determined work flows. It is anticipated that the riverbed data can be utilized for effective river management.