• Title/Summary/Keyword: river basin

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Study on the Selection of the Basin Characteristics Parameters in River Basin Using Satellite Images and GIS (위성영상(衛星映像)과 GIS를 이용한 하천유역(河川流域)의 유역특성인자(流域特性因子) 추출(抽出)추출 관한 연구(硏究))

  • Jo, Myung-Hee;Ahn, Seung-Seop
    • Journal of the Korean association of regional geographers
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    • v.4 no.1
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    • pp.121-134
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    • 1998
  • In this study, the satellite images and the GIS technique are used to select the basin characteristics parameters as the basis of water resources management of river basin. The study area is Geum-ho river basin and the hydrologic characteristics data are computed through the database of the basin characteristics parameters classified by subjects with 35 maps correspond to the study basin of 1:25,000 scale as the basic map. As the result, the drawing up of land use map through satellite image processing that provides the quantitative informations for the land is very efficient to analysis the extensive land use information of the basin, and exact analysis of mass surface data is possible and the feasibility of statistic computation between spatial subjects as it superpose on other subject map is ascertained. It is thought also that the analysis of the basin characteristics data can be utilized very effectively for the basin management and the analysis of basin surface area, once it is expressed numerically for database, since the superposition analysis with different subject map and the correlative analysis with the property data are possible although the tracing process of each subject in the basic map is not efficient. Especially, modification and renewal of the data for the change of land surface become easy, therefore more rapid and exact selection of the basin characteristics data and the construction of more efficient basin management plan are possible.

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Conversion Factors for Ten-Day Irrigation Duties of Paddy Rice in the Han River Basin (한강수계 논의 순별 단위용수량 변환계수)

  • 강문성;박승우;김현준;강민구
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.42 no.6
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    • pp.45-55
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    • 2000
  • Seasonal water requirements by paddy rice is important to water budgeting for the water resources planning at a basin scale. This paper compares the water requirements resulting from different approaches for the Han River Basin. The demands from the drought years of 1967 and 1968 were found to be significantly less than the irrigation standards. This may result in significant underestimation of the basin-wide water demands. A conversion factor method is proposed to define seasonal irrigation demands. The factor is defined from the ratios of the standards for each growing stage to the drought year demands. The results were compared satisfactorily with those from the irrigation standards, and readily applicable to the water resources planning.

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Basic Investigation on the Water Resource Development of the Principal Riever Basins for All Weather Farming (전천후농업용수원 개발을 위한 중요하천 수계별 기본조사의 실시)

  • 임은진
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.9 no.2
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    • pp.1291-1295
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    • 1967
  • This paper is a brief description on the task of the basic investigation of the water resource development of the principal river basins in this country for all- weather farming. In order to show how the people in the nation can best be benefited by further development of the water resources of the basins, this paper includes a description of the in individual basin's resource, its needs and problems, and its present and future development of the water resources within the natural drainage basin of the rivers are listed and their over-all results are summarised in the investigation report and separately filled. It is hoped that the government should continue and expand its detailed investigations of potential projects within the each principal river basin to obtain adequate information by which the Union of Land improvement Association can formulate a comprehensive plan for use of all the water resources of the basin's and select and recommend projects for successive stages of development.

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A STUDY ON THE PARAMETER ESTIMATION OF SNYDER-TYPE SYNTHETIC UNIT-HYDROGRAPH DEVELOPMENT IN KUM RIVER BASIN

  • Jeong, Sang-man;Park, Seok-Chae;Lee, Joo-Heon
    • Water Engineering Research
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    • v.2 no.4
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    • pp.219-229
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    • 2001
  • Synthetic unit hydrograph equations for rainfall run-off characteristics analysis and estimation of design flood have long and quite frequently been presented, the Snyder and SCS synthetic unit hydrograph. The major inputs to the Snyder and SCS synthetic unit hydrograph are lag time and peak coefficient. In this study, the methods for estimating lag time and peak coefficient for small watersheds proposed by Zhao and McEnroe(1999) were applied to the Kum river basin in Korea. We investigated lag times of relatively small watersheds in the Kum river basin in Korea. For this investigation the recent rainfall and stream flow data for 10 relatively small watersheds with drainage areas ranging from 134 to 902 square kilometers were gathered and used. 250 flood flow events were identified along the way, and the lag time for the flood events was determined by using the rainfall and stream flow data. Lag time is closely related with the basin characteristics of a given drainage area such as channel length, channel slope, and drainage area. A regression analysis was conducted to relate lag time to the watershed characteristics. The resulting regression model is as shown below: ※ see full text (equations) In the model, Tlag is the lag time in hours, Lc is the length of the main river in kilometers and Se is the equivalent channel slope of the main channel. The coefficient of determinations (r$^2$)expressed in the regression equation is 0.846. The peak coefficient is not correlated significantly with any of the watershed characteristics. We recommend a peak coefficient of 0.60 as input to the Snyder unit-hydrograph model for the ungauged Kum river watersheds

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A Study on the Soil Erosion by Landuse in the Imjin River Basin, DMZ of Cental Korea (임진강유역의 토지이용에 따른 지표침식에 관한 연구)

  • Lee, Min-Boo;Kim, Nam-Shin;Jin, Shizhu;Kim, Hang-Deok
    • Journal of the Korean Geographical Society
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    • v.43 no.3
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    • pp.263-275
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    • 2008
  • This Study deals with the comparative analysis on the estimation of surface soil erosion volume between South and North Korea using RUSLE model in Imjin River basin located on DMZ of Central Korea. Comparatively North Korea areas have been more eroded three times as much as South Korea parts. Because of cropland development such as com Held in the hillslope, in North Korea, more surface soil erosion and transportation to the river bed has given rise to frequent flood hazards. It seems that the study can dedicate to mitigation of environmental problems such as soil erosion and flooding in unaccessible Imjin River basin located on DMZ.

Estimation of Design Flood Discharge by Areal Ratio for Ungauged Basin (면적비를 적용한 미계측유역에서의 설계홍수량 산정방안)

  • Lee, Jiho;Park, Jaebeom;Song, Yangho;Jun, Hwandon;Lee, Jungho
    • Journal of Wetlands Research
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    • v.19 no.3
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    • pp.335-344
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    • 2017
  • In this study, We proposed a method to estimate the design flood by area ratio in an ungauged basin. For that, the discharge parameters was determined by calibration of observed data at the watershed outlet and then peak flow was estimated by area ratio. In order to verify suggested method, peak flow was compared the observed discharge of the small river basin and the design flood discharge of river implementation projects. The results were summarized as follows. As a result of comparing the discharge by the area ratio and observed discharge, the difference of peak flows were analysed 14 ~ 25%. When the discharge calculated with area ratio of small river was compared with the design flood discharge of river implementation projects, the relative error was analyzed to be less than 20%. It means that suggested method in this study is appropriate.

Quantitative Analysis of Human Impact on River Runoff in the Laohahe Basin through the Conceptual Xin'anjiang Model

  • Ren, Liliang;Vu, Van Nghi;Yuan, Fei;Li, Chunhong;Wang, Jixin
    • Proceedings of the Korea Water Resources Association Conference
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    • 2007.05a
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    • pp.15-21
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    • 2007
  • Due to a decreasing tendency of river runoff in the Laohahe River basin in North China, quantitative analysis was made with the aid of the conceptual Xinanjiang model under the background of nature climate variability as well as human-induced climate change according to the long-term observational hydrometeorological data. In the past, the human effect on surface water resources was estimated by investigating the impact of human activities on each item in the equation of water balance, so as to calculate water quantity of each item in the original natural status. It seems to be clear conceptually. It is appropriate just for the case of direct impact, such as water transfer from one basin to another, water storage by various scales of hydraulic projects, besides a huge amount of investigation and indeterminate statistics data when applied in practice. It is difficult for us to compute directly water consumption due to the implementation of measures for soil conservation, the improvement of farming techniques in agriculture, the growth of population in towns and villages, and the change of socioeconomic structure. In view of such situation, the Xinanjiang model was used to separate human impact from the climatic impact on water resources. Quantitatively human activity made river runoff decrease by 1.02, 50.67, 58.06 mm in 1960's, 1970's, 1980's, respectively, while by 97.2 mm in 1990's in the sense of annual average in the Laohahe River basin.

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ASSESSMENT AND CONTROL OF TOTAL NUTRIENT LOADS IN WATERSHED AND STREAM NETWORK IN SOUTH-WEST TEXAS

  • Lee, Ju-Young;Choi, Jae-Young
    • Water Engineering Research
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    • v.7 no.1
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    • pp.1-8
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    • 2006
  • Recently, the population growth and agricultural development are rapidly undergoing in the South-West Texas. The junction of three river basins such as Lavaca river basin, Colorado-Lavaca Coastal basin and Lavaca-Guadalupe Coastal basin, are interesting for non-point and point source pollutant modeling: Especially, the 2 basins are an intensively agricultural region (Colorado-Lavaca Coastal/Lavaca-Guadalupe Coastal basins) and several cities are rapidly extended. In case of the Lavaca river basin, there are many range land. Several habitat types wide-spread over three relatively larger basins and five wastewater discharge regions are located in there. There are different hazardous substances which have been released. Total nutrient loads are composed of land surface load and river load as Non-point source and discharge from wastewater facilities as point source. In 3 basins region, where point and non-point sources of poll Jtion may be a big concern, because increasing fertilizers and pesticides use and population cause. This project objective seeks to how to assess and control the accumulation of non-point and point source and discuss the main impacts of agriculture and environmental concern as non-point source with water quality related to pesticides, fertilizer, and nutrients and as point source with wasterwater discharge from cities. The GIS technique has been developed to aid in the point and non-point source analysis of impacts to natural resource within watershed. This project shows the losses in $kg/km^2/year$ of BOD (Biological Oxygen Demand), TN (Total Nitrogen) and TP (Total Phosphorus) in the runoff from the surface of 3 basins. In the next paper, sediment contamination will show how to evaluate in Estuarine habitats of these downstream.

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Distribution of large jar coffin on Location Characteristics of the Jar Coffins in the Yeongsan River Basin (영산강 유역 옹관묘의 입지특성으로 본 대형옹관의 유통)

  • Lee, Ae Jin;Park, Ji Hoon
    • Journal of the Korean association of regional geographers
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    • v.22 no.4
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    • pp.843-855
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    • 2016
  • The objective of this study is to find out geomorphological characteristics of historical ruins where people produced and consumed large jar coffins excavated in the Yeongsan river basin using Fluvio-Marine Plains from detailed soil map. For this purpose, we chose the 21 consumption sites. The results are as follows. 21 consumption sites located in the region of upper limit of tidal internal in Yongsan River and tributary rivers. Among these, 18 Consumption sites has high accessibility with Fluvio-marine plains. This means that Consumption remains of Yongsan River basin have been located to area available for distribution from production sites.

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Retrieval of Key Hydrological Parameters in the Yellow River Basin Using Remote Sensing Technique

  • Dong, Jiang;Jianhua, Wang;Xiaohuan, Yang;Naibin, Wang
    • Proceedings of the KSRS Conference
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    • 2002.10a
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    • pp.721-727
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    • 2002
  • Precipitation evapotranspiration and runoff are three key parameters of regional water balance. Problems exist in the traditional methods for calculating such factors , such as explaining of the geographic rationality of spatial interpolating methods and lacking of enough observation stations in many important area for bad natural conditions. With the development of modern spatial info-techniques, new efficient shifts arose for traditional studies. Guided by theories on energy flow and materials exchange within Soil-Atmosphere-Plant Continuant (SPAC), retrieval models of key hydrological parameters were established in the Yellow River basin using CMS-5 and FengYun-2 meteorological satellite data. Precipitation and evapotranspiration were then estimated: (1) Estimating tile amount of solar energy that is absorbed by the ground with surface reflectivity, which is measured in the visible wavelength band (VIS): (2) Assessing the partitioning of the absorbed energy between sensible and latent heat with the surface temperature, which was measured in the thermal infrared band (TIR), the latent heat representing the evapotranspiration of water; (3) Clouds are identified and cloud top levels are classified using both VIS and TIR data. Hereafter precipitation will be calculated pixel by pixel with retrieval model. Daily results are first obtained, which are then processed to decade, monthly and yearly products. Precipitation model has been has been and tested with ground truth data; meanwhile, the evapotranspiration result has been verified with Large Aperture Scintillometry (LAS) presented by Wageningen University of the Netherlands. Further studies may concentrate on the application of models, i.e., establish a hydrological model of the Yellow river basin to make the accurate estimation of river volume and even monitor the whole hydrological progress.

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