• Title/Summary/Keyword: Lake

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Case study on the Chinese polluted river and lake restoration under the sponge city construction

  • Liu, Jian;Yuan, Zhan;Liu, Yan;Wu, Lingyi
    • International conference on construction engineering and project management
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    • 2017.10a
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    • pp.353-361
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    • 2017
  • In order to improve the urban ecological environment, the central government has developed a series of water pollution control policies and measures since April 2015, and required local governments to complete the work of the polluted river and lake restoration within specified period. Moreover, the polluted river and lake restoration has been selected as a key evaluation indicator of achievements of the sponge city construction implemented since April 2015. This paper describes how to apply the sponge city construction technology to rehabilitate the polluted rivers and lakes through the polluted water treatment project in Xinghan New Area, Hanzhong and the polluted Huaguping River restoration project in Pingshan District, Shenzhen. The experience and lessons of the polluted river and lake restoration are summed up. Some measures to solve existing problems are put forward.

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A portal quadrad with triple hepatic arteries

  • Claire E Stoudemire;Caitlin N Sachsenmeier;Brittney L Link;Faith M Klein;Randy Kulesza
    • Anatomy and Cell Biology
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    • v.56 no.2
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    • pp.276-279
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    • 2023
  • The arterial support of the liver is most commonly from the celiac trunk via the proper hepatic artery (PHA). The PHA divides into left and right branches: the right hepatic artery (RHA) supplies the right and caudate lobes while the left hepatic artery (LHA) supplies the left and quadrate lobes. Aberrant hepatic arteries are relatively common, and the most frequent contributors are the superior mesenteric artery and left gastric artery. Herein we present findings from postmortem dissection of an abdominal cavity that revealed a rare combination of reported variations. Specifically, this subject had three extrahepatic arteries - a replaced LHA (rLHA), a PHA, and a replaced RHA (rRHA). The rLHA originated from the left gastric and the rRHA originated from the superior mesenteric artery. Knowledge of these variations is important for surgical and radiological procedures to avoid complications during treatment and improve patient outcomes.

Estimating the Nitrogen and Phosphorus Loads of Wintering Waterfowl Feces in Lake Paldang (팔당호에서 겨울철새 분변에 의한 질소와 인 오염부하량 산정)

  • Lee, Jangho;Park, Hae-Kyung
    • Journal of Korean Society on Water Environment
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    • v.26 no.2
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    • pp.311-316
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    • 2010
  • We estimated the nitrogen and phosphorus loads of wintering waterfowl feces in Lake Paldang. The average number of individual birds that belonged to Anatidae species was 2,852.5 from 2005 to 2008 in Lake Paldang. The number of Anatidae reached 97.4% of the total number of individual birds. For evaluating the loading amounts of N and P by waterfowl to Lake Paldang, the feces dry weight (g/day) of each Anatidae species was estimated by multiplying the body weight of the each bird by 2.25% and assumed that N and P in feces contain 1.46% and 0.33%, respectively. We assigned probability 1/3 to the nutrient decomposition of the bird feces in water. The nitrogen loading by wintering waterfowl feces was 0.06 ton/year and the phosphorus loading was 0.001 ton/year. These amounts were 0.0002% of all N loadings and 0.0001% of all P loadings. Therefore the wintering waterfowl might have little impact on the water quality in terms of eutrophication in Lake Paldang.

A Study on Grain Size Dependency of Selected Heavy Metals in the Surface Sediment of Lake Paldang (팔당호 표층 퇴적물에 함유된 중금속의 입도 의존성에 관한 연구)

  • Shin, Kyung-Yong;Jun, Sang-Ho
    • Journal of Environmental Health Sciences
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    • v.38 no.5
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    • pp.424-430
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    • 2012
  • Objective: The purpose of this study was to present the standard deviation of the elemental normalization of concentration of selected heavy metals in the surface sediment of Lake Paldang. Methods: Grain size dependency of selected heavy metal concentrations in the surface sediments of Lake Paldang was analyzed by the extrapolation method. The heavy metal concentrations were the sum of all fractions. Results: Cd and Cu showed an increase of the coefficient of determination($r^2$) in the fractional content of particle size, from <256 ${\mu}m$ to <20 ${\mu}m$, and a decrease from <20 ${\mu}m$ to <1 ${\mu}m$. The normalized concentration of Cd and Cu by extrapolation at 50% <20 ${\mu}m$ were 0.8 mg/kg, 37.0 mg/kg, 57.6 mg/kg and 201.7 mg/kg respectively. Conclusions: The normalized concentrations in the sediment of Lake Paldang are 1.5-2.0 times higher than mean average concentration. We concluded that in interpretation of heavy metal concentration in the sediment of Lake Paldang, normalization of grain size dependency should be considered.

Trophic State and P Loading Analysis for Juam Lake (주암호 영양상태 및 인부하 분석)

  • Bae, Sang-Ok;Lee, Yong-Woon;Lee, Sung-Woo;Chung, Seon-Yong
    • Journal of Environmental Impact Assessment
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    • v.9 no.4
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    • pp.291-300
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    • 2000
  • Juam lake is a major water reservoir for the industrial and agricultural activities as well as the residental life of Kwangju and Chonnam regions. However, the water quality of the lake is getting worse due to a large quantity inflowing to the lake. The excessive growth of algae by the overfertilization may result in water treatment problems and also the interference with desirable water uses of navigation, aesthetics, recreation, and aquatic ecosystem. Thus the purpose of this study is to investigate the species and their amount of planktons in the lake and the relationship between the P loading amount and the chlorophyll-a used as a primary productivity index. The results of the investigation show that (1) the predominant species of algae are Microcystis aeruginosa, Anabaena affinis, Melosira granulata, Synedra acus, and Coelastrum cambricum, (2) the trophic state of the lake can be classified as eutrophic, and (3) there is close relation between the P loading amount and the chlorophyll-a.

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Photosynthesis-Irradiance Relationship and Primary Production of Phytoplankton in Lake Gocheonam

  • Jung, Min-Kyung;Lee, Ok-Hee;Cho, Kyung-Je
    • Korean Journal of Environmental Biology
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    • v.22 no.4
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    • pp.524-531
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    • 2004
  • Photosynthetic activities and primary production of phytoplankton were investigated in Lake Gocheonam from October 1999 to August 2000. As an estuary lake with a barrage in the Southwestern coast of the Korean peninsula, the lake has received more attention after it became known as the habitat of large population of rare and endangered bird- Baikal Teal. As the lake had high algal biomass ranging from $20\mu{g}\;chl-aL^{-1}\;to\;125\mu{g}\;chl-aL^{-1}$ in average values and rich eutrophication indicator species, the freshwaters were in a very productive or hypertrophic state. In the results obtained from the phytoplankton incubation in the laboratory, the maximum photosynthetic rate $(P_{max})$ varied according to seasons and sampling stations. Photo- synthetic activities were higher during the warm season than the cold seasons and the serial order of $P_{max}$ was August dominated with Microcystis, April with Chlamydomonas and Nitzschia, October with Chlamydomonas and January with Stephanodiscus. The water of the lake was persistently turbid throughout the year due to strong winds from the adjacent sea. Despite the water turbidity, the phytoplankton productions estimated from a mathematical model had very broad range from 18mg C $m^{-2}day^{-1}\;to\;10,300mg\;C\;m^{-2}day^{-1}$.

The Study on Decline Plan of Primary Production Organic Matter of Uiam Lake Basin (의암호 유역에서 발생하는 자체생산 유기물 저감방안에 관한 연구)

  • 허인량;이건호;함광준;최지용;정의호
    • Journal of Environmental Health Sciences
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    • v.30 no.1
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    • pp.50-58
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    • 2004
  • The present study was designed to evaluate primary production organic matter in basin of lake around by execution of total maximum daily loading. BOD influent loading of Uiam lake was 2,819 kg/day, which was less then 28.3 percent, total effuluent loading as 3,619 kg/day, in comparision with BOD, total nitrogen influent loading was 4,681 kg/day, which was less then 10.0 percent, total effuluent loading as 5,150 kg/day. But in case of total phosphors influent loading was 73.3 kg/day, which was more then 34.2 percent, total run off loading as 48.3 kg/day. The result of survey reduction plan of primary production organic matter in basin of lake around which objectives of abstract is as follows. First plan was reduction of primary production organic matter by moving the outlet of municipal wastewater treatment center from present place to lake downstream. Secondary plan was improvement by diffusion type of outlet municipal wastewater treatment center. The third plan was reduction of environmental impact by passing and storing of municipal wastewater. Finally plan was decline water surface level which was present hydrouric retention time was reduction from 7.6 day to 6.0 day per meter.

Analysis of Algal Species and Movements in Juam Lake (주암호의 조류 출현종 및 거동 분석)

  • Lee, Yong Woon;Chung, Seon Yong;Bae, Sang Ok;Moon, Yang Soo
    • Journal of Environmental Impact Assessment
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    • v.8 no.4
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    • pp.37-45
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    • 1999
  • Juam Lake is a major water resource for the industrial and agricultural activities as well as for the resident life of Kwangju and Chonnam regions. However, the water quality of the lake is getting worse due to a large quantity of pollutant inflowing to the lake. The excessive growth of algae by the overfertilization may result in water treatment problems and also the interference with desirable water uses of navigation, aesthetics, recreation and fish maintenance. Therefore, the purpose of this study is to analyze algal species and movements in Juam Lake in order to use as basic data in making the countermeasure to achieve the water quality goal of the lake. The results of the analysis show that (1) the predominant species of algae are Microcystis aeruginosa, Anabaena affinis, Melosira granulata, Synedra acus, and Coelastrum cambricum, (2) their groups are changed in order of diatoms, green algae, and blue-green algae with the lapse of time, and (3) the distance of the vertical movements of algae for 24 hours is about 2m.

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Change of Groundwater Quality derived from Contaminant Sources (오염원에 의한 지하수 수질의 변화)

  • Bae, Sang-Kuen
    • Journal of Environmental Science International
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    • v.4 no.5
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    • pp.75-75
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    • 1995
  • In order to provide for the guidance on groundwater quality monitoring network design and also, to suggest the index to the solution of the contaminated groundwater remediation problems in the lake watershed, it is necessary to analyze the contaminant transport in the groundwater. The solute transport was analyzed in the lake watershed to investigate the behavior of the injected contaminant sources depend on the relationships between the point of contaminant sources and position of the lake. Three hypothetical groundwater flow systems, which is composed of a flow-through lake and two solute sources, were considered. The lakes located in the upper, middle, and lower portions of a watershed respectively. The transported contaminant was numerically simulated for five years by using MT3D contaminant transport model under the three-dimentional steady state conditions. From the above simulations, it can be concluded that the contaminant concentration was high as the contaminant source located at the upper position of a watershed, and the influence of the contaminant injection was large as the solute source located at the lower position. When the injection of contaminant was continued for one year without regard to the position of contaminant source and the lake, the influence of contaminant source was reached to bedrock.

Change of Groundwater Quality derived from Contaminant Sources (오염원에 의한 지하수 수질의 변화)

  • 배상근
    • Journal of Environmental Science International
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    • v.4 no.5
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    • pp.461-468
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    • 1995
  • In order to provide for the guidance on groundwater quality monitoring network design and also, to suggest the index to the solution of the contaminated groundwater remediation problems in the lake watershed, it is necessary to analyze the contaminant transport in the groundwater. The solute transport was analyzed in the lake watershed to investigate the behavior of the injected contaminant sources depend on the relationships between the point of contaminant sources and position of the lake. Three hypothetical groundwater flow systems, which is composed of a flow-through lake and two solute sources, were considered. The lakes located in the upper, middle, and lower portions of a watershed respectively. The transported contaminant was numerically simulated for five years by using MT3D contaminant transport model under the three-dimentional steady state conditions. From the above simulations, it can be concluded that the contaminant concentration was high as the contaminant source located at the upper position of a watershed, and the influence of the contaminant injection was large as the solute source located at the lower position. When the injection of contaminant was continued for one year without regard to the position of contaminant source and the lake, the influence of contaminant source was reached to bedrock.

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