• Title/Summary/Keyword: rivers

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Building capacity for ecological assessment using diatoms in UK rivers

  • Kelly, Martyn
    • Journal of Ecology and Environment
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    • v.36 no.1
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    • pp.89-94
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    • 2013
  • Diatoms have become an integral part of the UK's freshwater monitoring strategy over the past two decades, mostly in response to increasingly stringent European Union (EU) legislation. The use of diatoms is based on strong correlations between diatom assemblages and environmental variables, and from knowledge of the "expected" (= "reference") state of each river. The nationwide overview of the ecological health of rivers this gives allows those stretches of rivers which fail to meet EU criteria to be identified. This, in turn, allows appropriate remediation measures to be planned. Because diatom assemblages vary in space and time, even within a single water body, effective use of diatoms requires a consistent approach in order to minimise uncertainty. This includes the use of methods which comply with European Standards, a training and accreditation scheme for analysts, and a suite of quality assurance methods. Those aspects of uncertainty that cannot be readily controlled have been quantified and all estimates of ecological status are accompanied by the appropriate "confidence of class" and "risk of misclassification". This, in turn, helps planners prioritise those locations which are most likely to benefit from remediation.

Ecological Consideration for Restoration of the Degraded Urban River

  • Lee, Chang-Seok;You, Young-Han
    • 한국생태학회:학술대회논문집
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    • 2002.08a
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    • pp.113-118
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    • 2002
  • Vegetation and riverine structures were compared among urban and several semi-natural rivers by applying direct gradient analysis and ordination method. Urban rivers showed different species composition from the semi-natural ones. Species composition of semi-natural rivers depended on the geographical positions, such as the upstream, midstream, and downstream and on micro-topographies, such as the waterside, flooding bed, and embankment. Semi-natural rivers showed gentle change in micro-topography, whereas urban one did not so. Our restoration plan to improve the ecological quality of the degraded urban river by imitating semi-natural river was prepared based on those data.

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A Review of the Master Plan for Four Major Rivers Restoration Project

  • Park, Chang-Kun
    • Journal of Environmental Impact Assessment
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    • v.18 no.6
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    • pp.411-417
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    • 2009
  • Lately the master plan for the Four Major Rivers Restoration Project has been released by the Ministry of Land and Maritime Affairs and relevant ministries. According to the master plan compared with the interim report made on 15 December 2008, the number of weirs for irrigation has increased from 5 to 16, the amount of dredging has increased from 220 million cubic metres to 570 million cubic metres, and the total cost estimated has increased from 14 trillion won to 22 trillion won. A critical review of the master plan by some research group will be summarized focused upon budget, objectives, securing water resource, dredging, and flood control etc. After various experts' forums and field surveys, it is concluded that the government should implement a joint-research program on assessing the impact of the project together with experts and citizens' groups as co-partners, in order to truly save or restore the four major rivers.

Resistance Factors and Relationships for Measurements in Fluvial Rivers (충적하천 실측자료의 저항계수와 관계식)

  • Lee, Jong-Seok;Julien, Pierre Y.
    • The Journal of the Korea Contents Association
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    • v.12 no.7
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    • pp.445-452
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    • 2012
  • This study is used to analyze the distribution of resistance factors and the relationships of flow resistance with the field measurements which consist of the total 2,604 rivers for 1,865 bed material in natural channels and 739 vegetation in vegetated channels. Resistance factor relationships and distribution range of Manning roughness coefficients and Darcy-Weisbach friction coefficients by the regression analysis are derived from the power law form as a function of flow discharge and friction slope with bed materials and vegetations in natural and vegetated rivers, respectively.

Ecological Consideration for Restoration of the Degraded Urban River

  • Lee, Chang-Seok;Yon, Young-Han
    • The Korean Journal of Ecology
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    • v.25 no.4
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    • pp.247-252
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    • 2002
  • Vegetation and riverine structures were compared among urban and several semi-natural rivers by applying direct gradient analysis and ordination method. Urban rivers showed different species composition from the semi-natural ones. Species composition of semi-natural rivers depended on the geographical positions, such as the upstream, midstream, and downstream and on micro-topographies, such as the waterside, flooding bed, and embankment. Semi-natural rivers showed gentle change in micro-topography, whereas urban one did not so. Our restoration plan to improve the ecological quality of the degraded urban river by imitating semi-natural river was prepared based on those data.

Review on Water Quality and Achievement of Water Quality Goal by Various Evaluation Methods in Geum River (다양한 평가기법을 이용한 금강 대권역의 수질 및 목표수질기준 달성도 평가)

  • Lee, Jae-Woon;Jeong, Hye-Sung;Yoon, Jung-Hee;Cheon, Se-Uk
    • Journal of Environmental Impact Assessment
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    • v.17 no.6
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    • pp.373-380
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    • 2008
  • The Ministry of Environment plans to improve quality of water which is achieved over 85% in rivers and 94% in lakes of the whole country as "Good Water" until 2015. Also, the law of evaluation of water quality and water quality goal were made newly. So, the water quality has evaluated by using new law since 2007. This study evaluated whether "Good Water" and" Water Quality Goal" were achieved or not in 22 middle-sized districts and major 10 lakes of Geum river. The achievement rates of rivers decreased and the achievement rates of lakes mostly were the same for 5 years. In 2007, the achievement rates of "Good Water" were 50% in rivers and 50% in lakes. The achievement rate of "Water Quality Goal" were 59.1% in rivers and 20% in lakes. The water quality in 2007 was evaluated worse than last year in case of rivers. The evaluations of Korea-Comprehensive Water Quality Index(K-CWQI) showed that achievement rates of "Water Quality Goal" were 81.8% in rivers and 0% in lakes. The statistical correlation analysis showed that correlations between BOD and COD were meaningful at the downstream, compared to upstream, generally. In case of lakes, correlations between COD and temperature were meaningful. Also, correlations between COD and Chl-a were meaningful. The Trophic State Index ($TSI_{KO}$) showed that the half of lakes are major over eutrophic status in lakes. These analytical methods such as K-CWQI, $TSI_{KO}$, statistical correlation analysis could be additionally helpful for evaluation of water quality and provide basis data for understanding characteristics of watershed in Geum river.

Changes in citizens' trust about '4 Rivers Project' and the Prospect of the Scientific-Tecnnological Citizenship (4대강 사업에서 시민의 신뢰 변화와 과학기술 시민자격의 전망)

  • Jeong, Taeseok
    • Journal of Science and Technology Studies
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    • v.15 no.1
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    • pp.69-107
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    • 2015
  • In this article, I try to understand the changing patterns of 'politics of expertise' by looking at the change of the citizens' opinion on '4 Rivers Project', particularly the change of citizens' trust in expert, through data analysis on 'Citizen Opinion Survey on Science and Technology'. Findings are as follows: The reliability of government and the pros side experts downed, on the other hand, the reliability of the opposite side experts and environmental groups have maintained or slightly increased. This shows the fact that '4 Rivers Project' is the field of political confrontation surrounding the expertise. The government decision-making process on '4 Rivers Project' can be examined from the perspective of 'the politics of expertise', in the sense that the process is related to the utilization of scientific and technological expertise-power surrounding the project feasibility. The facts that citizens are interested in scientific-technological and ecological issues which are largely affected by expertise, and they think that the 4 Rivers Project affects the their daily lives, are the result of rising 'scientific-technological citizenship'.

Development of an Approximate Cost Estimating Model for River Facility Construction at Planning Stage (이.치수형 하천공사 개략공사비 산정모델 개발)

  • Lee, Si-Wook;Lee, Jeong-Yoon;Park, Sung-Hwan;Choi, Jae-Joon;Woo, Sung-Kwon
    • Korean Journal of Construction Engineering and Management
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    • v.10 no.5
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    • pp.95-103
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    • 2009
  • The case of rivers facilities works, expense the standard unit cost for the quality and a rough public corporation expense estimating of the rivers public corporation which is fixed form with the information available which it follows basic design phase absently and possibility of fluctuation. It exists many difficulties in rough public corporation expense estimating. The rivers public corporation expense rough estimating method of existing produces does not exist the amount of material of representative section of the rivers dike and the rough public corporation expense estimating method which is systematic with the method which multiples the seniority (M). The research sees the rough public corporation expense predictive model from the planning stage which is not basic design to consider the quality of the rivers facility public corporation. From this study, it can prevent the waste of national budget from the general public corporation and is more accurate and public corporation expense production possibly.

"Ecoturism Networks 10" around the Areas Bordering National Rivers in South Korea (국가하천변 생태관광 네트워크 10선)

  • Lee, Gwan-Gyu;Lee, Sang-Hyuk
    • Journal of Environmental Impact Assessment
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    • v.21 no.1
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    • pp.41-51
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    • 2012
  • To select 10 representatives for the ecotourism networks around the areas bordering national rivers in Korea, the spatial ranges for ecotourism have been established, the ecotourism potential analyzed, and the ecotourism resources information collected by the Regional Environmental Offices and the Korea National Park Service has undergone reviews, amendments, supplements, and verification processes through familiarization tour previews, and the following main results have been derived. First, the spatial ranges of the eco-tourism networks have been set as the watershed areas that include areas around the four major rivers and the rivers. Second, the areas with high potential value for ecotourism were selected through the analysis of ecotourism potential. Since EGIS was used for the analysis, it was inevitable that insufficient amount of localized information was reflected, and the use of the results as reference for the potential would be feasible. Third, it was possible, by reviewing, amending and complementing the results of ecological resource information collected by the Regional Environmental Offices and the Korea National Park Service, to select 50 representative ecological resources around the national rivers. The selected resources were considered for the adjacency, attractiveness of ecological resources, and uniqueness of the national rivers, and they were derived by screening expert advice, official opinion, and geographical analysis information. Fourth, 10 representative ecotourism networks based on watershed areas were selected, and suitable themes were given based on the resource characteristics. Fifth, the appropriateness for ecotourism has been confirmed, with the familiarization tour previews and survey results, preservation of the future ecotourism resources, and the establishment of the foundation as the basis. In the future, the remaining 9 ecotourism networks would also need to undergo a verification process such as familiarization tours. It is deemed that, through future ecotourism contests, if the programs that select locally-pioneered tourism programs resulting from the capacities of local entities and residents, then it would be more effective in discovering resources that are more localized and of higher regional value.

Clay mineral distribution and provenance in surface sediments of Central Yellow Sea Mud

  • Koo, HyoJin;Lee, YunJi;Kim, SoonOh;Cho, HyenGoo
    • Geosciences Journal
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    • v.22 no.6
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    • pp.989-1000
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    • 2018
  • The provenance of the Central Yellow Sea Mud (CYSM) in the Yellow Sea has been attracted a great deal of attention over the last three decades, but a consensus is not yet reached. In this study, 101 surface sediment samples collected from the CYSM were investigated to determine provenance and transport mechanisms in the area using the clay minerals and major element components. The Huanghe sediments are characterized by higher smectite, but the Changjiang sediments are more abundant illite contents. Western Korean rivers contain more kaolinite and chlorite than do Chinese rivers. The Chinese rivers have higher $Fe_2O_3$, MgO, and CaO than the Korean rivers at the same $Al_2O_3$ concentration. Therefore, the clay minerals and major element concentrations can be useful indicator for the source. Based on our results, we suggest that the surface sediments in CYSM were composed mainly of Changjiang sediments, mixed a partly with sediments from the Huanghe and the western Korean rivers. Although the northwestern part of CYSM is proximate to the Huanghe, the contents of smectite and CaO were extremely low. It could be evidence that the Huanghe materials do not enter directly into the CYSM due to the Shandong Peninsula Front. Considering the oceanic circulation in the Yellow Sea, the Changjiang sediments could be transported eastward with the Changjiang Diluted Water and then mixed in CYSM via the Yellow Sea Warm Current (YSWC). Huanghe sediments could be provided by coastal currents (Shandong Coastal Current and Yellow Sea Coastal Current) and the YSWC. In addition, sediments from western Korean rivers might be supplied into the CYSM deposit via the Korean Coastal Current, Transversal Current, and YSWC.