• 한국수자원학회논문집
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• 제51권3호
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• pp.207-219
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• 2018

본 연구에서는 확률밀도함수의 서식처 적합도 지수를 사용하여 도심하천구간과 자연하천구간에서 유량점증방법론(Instream flow Incremental Methodology, IFIM)을 토대로 피라미 서식처의 생태유량을 모의하였다. 이와 같은 방법을 적용하기 위하여 본 연구에서는 PHABSIM 모형을 사용하였다. 본 연구에서는 서식처 적합도 지수(Kang, 2010)를 기초로 확률밀도함수의 매개변수를 조정하여 확률밀도함수의 서식처 적합도 지수를 개발하여 생태유량을 분석하였다. 그 결과, 도심하천구간에서는 정규분포가 자연하천구간에서는 2변수 log-pearson 분포가 Kang (2010)의 생태유량에 가장 근접하는 경향을 보였다. 확률밀도함수에 의한 서식처 적합도 지수와 하천구간별로 생태유량을 모의하여 확률론적 방법을 적용한 생태유량 산정기법을 제안하였다.

• 한국농공학회논문집
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• 제62권6호
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• pp.51-62
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• 2020

The objective of this study was to estimate an optimum ecological flow rate in the Banbyeon stream based on the two representative fish species. Hydraulic stream environment was simulated with HEC-RAS for two water flow regimes and used for the PHABSIM hydraulic simulation. A dominant species of Zacco platypus and an endemic species of Squalidus chankaensis tsuchigae were selected as the representative fishes whose habitat conditions were evaluated for the spawning and adult stages. Weighted usable area (WUA) was estimated based on habitat suitability index (HSI) and PHABSIM habitat simulation. Overall deep water zone in the stream demonstrated greater WUA which implies better habitat status. The estimated WUA for Zacco platypus as the dominant species was about five times greater than Squalidus chankaensis tsuchigae at the stream flow of 12 ㎥/s. The optimum ecological flow rates were 15 ㎥/s and 25 ㎥/s for the respective spawning and adult stages of Zacco platypus, while 5 ㎥/s was estimated for both the life cycles of Squalidus chankaensis tsuchigae. Assuming that the dominant species may survive better in wider flow regimes, the optimum ecological flow rate should be determined rater based on the endemic species and flow rate of 5 ㎥/s was suggested for the Banbyeon stream.

• 한국초전도ㆍ저온공학회논문지
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• 제22권2호
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• pp.17-20
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• 2020

Comprehensive utilization of tungsten tailings resources not only solves environmental problems but also creates huge economic benefits. The high content of iron impurity in tungsten tailings will have adverse effect on the downstream comprehensive utilization, whether flotation or pickling. In this paper, the Superconducting High Gradient Magnetic Separation(S-HGMS) is used to remove of Fe impurities from tungsten tailings. The optimal experimental parameters are as follows: background magnetic induction intensity is 3.0T, slurry flow velocity is 500ml/min. The Fe removal rate of Fe was 68.8% and the recovery rate was 59.53%.

• 한국환경복원기술학회지
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• 제14권5호
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• pp.69-79
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• 2011

This study assessed the subsurface runoff and peak flow reduction in rain gardens. The results showed that the highest water retention was found in rain garden mesocosms in which Rhododendron lateritium and Zoysia japonica were planted, followed by mesocosms in which either R. lateritium or Z. japonica was planted, and the lowest water retention rate was found in non-vegetated control treatment mesocosms(${\alpha}$ < 0.05). Although higher rainfall intensity caused a decrease of peak flow reduction in both vegetated and non-vegetated treatments, peak flow reduction was the greatest in mesocosms with mixed plants. A rain garden can be an effective tool for environment-friendly stormwater management and improving ecological functions in urban areas. Depending on the purpose such as delaying runoff or increasing infiltration, various plant types should be considered for rain garden designing.

• 생태와환경
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• 제42권3호
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• pp.374-381
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• 2009

본 연구는 용담댐 직하류 하천정비가 시행되고 있는 구간에서 하도특성과 어류 서식처를 고려하여 생태학적 유지유량을 정량적으로 산정하였다. 댐 건설 전과 후의 하도특성 변화에서 1988년부터 2004년까지 최심하상고 및 하폭의 변동이 거의 없이 안정적이었지만, 하상토 입경은 2004년에 조금 가늘어지고 있다. 어류를 조사한 결과, 칼납자루 등 4과 11종이 채집되었다. 그 중에서 잉어과 참갈겨니가 우점하였고, 쉬리가 아우점하였다. PHABSIM모형을 이용하여 하도특성을 고려한 서식처 적합도(HSC) 지수를 모의한 결과, 감동지구와 대티지구에서 참갈겨니의 최적유량은 $13.90\sim12.60\;m^3\;s^{-1}$범위이며, 쉬리의 최적유량은 $15.50\sim11.60\;m^3\;s^{-1}$범위이었다. 부남지구에서, 참갈겨니의 최적유량은 $7.00\;m^3\;s^{-1}$이며, 쉬리의 최적유량은 $7.00\;m^3\;s^{-1}$이었으며, 용담 유황자료와 비교한 결과 평수량과 풍수량 사이에 해당하는 유량이었다.

• Journal of Ecology and Environment
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• 제30권2호
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• pp.127-133
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• 2007

The effects of water flow rate and phytoplankton concentration on the growth of the sandy shore clam Gafrarium tumidum was investigated in a laboratory flume study using a $3{\times}3$ factorial design. After 60 days, shell length, shell weight and tissue dry weight increased significantly with phytoplankton concentration. For the effect of flow rate, growth was faster when flow rate increased from low to medium level; further increases in flow rate, however, either did not sustain faster growth or resulted in a reduction in growth. The condition index (CI) of a standard-sized clam was significantly higher at low flow rate than at medium and high flow rates and was negatively correlated with phytoplankton concentration. The uncoupled growth of shell and tissue in response to flow rate and phytoplankton concentration may be adaptations to low food environments, so that energy can either be stored to sustain life or reserved for gametogenesis during the reproductive period.

• The Korean Journal of Ecology
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• 제6권2호
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• pp.81-89
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• 1983

The change of environmental factors with flow rates were studied quantitatively for two rivers, the Nakdong River and the Sin stream, which have different basins in ecosystem structures, during short period after a heavy rain. In the Nakdong River, transparency, DO, alkalinity and hardness were negatively correlated with the flow rate by logarithmic function, but the concentration of SiO2 was relatively constant regardless of the flow chage. In the Sin stream, transparency, alkalinity, hardness and the concentration of NH3-N, NO2-N and SO4= showed negative correlation with the flow rate by logarithmic function. The ratios of maximum to minimum values for aquatic environmental factors during the samller than that for flow rate in the respective rivers (28 in the Nakdong R.; 50 in the Sin S.). Immediately after the heavy rain, the concentrations of NO2-N, NH3-N and PO4-P in the Sin stream were 8, 6 and 1 times as high as those in the Nakdong River, respectively, but in the stable flow state, those became 94, 25 and more than 10 times, respectively. The load for most of the dissolved environmental constituents changed similarly to the flow rate in both rivers. It is notable that, at the stable flow state, the loads for NH3-N (59g/sec) and NO2-N (3.3g/sec) in the Sin stream were 4.3 and 1.3 times as high as those in the Nakdong River.

• 한국농공학회논문집
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• 제64권4호
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• pp.55-64
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• 2022

The objectives of this study were to assess physical habitat suitability of fish species for different life cycle stages and to suggest appropriate ecological stream flows in a Bokha downstream reach. A dominant species of Zacco platypus was selected as the study fish of which three stages of spawning, juvenile and adult in life cycle were considered into assessment. The stream hydraulic environment was calibrated with HEC-RAS before the PHABSIM simulation. The hydraulics of flow velocity and depth were used to estimate Weighted Usable Area (WUA) by multiplying respective habitat suitability indices with stream area. Overall the WUAs tend to be great in gentle slopes with relatively shallow water depth regions. Maximum WUAs, ie, candidate for ecological flow rates were 1 m³/s, 7 m³/s and 8 m³/s for the respective spawning, juvenile and adult stages of Zacco platypus. Since the ecological flow rates for juvenile and adult stages appeared to be is greater than the abundant flow rate (3.67 m³/s) for the study reach, additional water supply may be needed but should be cautious to avoid the spawning period of Apr through May from the stream water management perspective.

• 한국환경복원기술학회지
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• 제24권1호
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• pp.69-80
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• 2021

The new town in Korea, developed as a large-scale housing plan, has created urban ecological corridors to provide habitat and movement routes to wildlife and to promote natural ecological flow. This study aimed to investigate the use of wildlife in 10 ecological corridors in Gwanggyo New Town through camera trap technology and confirm effectiveness by identifying environmental factors affecting the use of wildlife's urban ecological corridors. Our researchers installed 20 unmanned sensor cameras at each the entrance and exit of the ecological corridors, and monitored urban wildlife for 10 weeks. According to the monioring results, the main species in Gwanggyo New Town were identified not only raccons, cats, water deer, korean hare and avain but also magpies, dove, eurasian tree sparrow, ring-necked pheasant, and eurasian jay. The number of uses ecological corridors of urban residents was 801(13.49%), as high as that of urban wildlife (1,140, 19.20%), which was judged to have disturbed the use of ecological corridors by wildlife. However, most dominant species of urban wildlife are nocturnal so that, it was judged that they share home range with urban residents at a time interval. In addition, according to the correlation analysis results between the mammal using rate of the urban ecological corridors and environmental factors(ecological corridor-specific length, ecological corridor-specific width, cover degree, shielding degree, connected green area, separation of movement routes, and presence of streetlights), environmental factors were not statistically significant. However, the more the area of green space connected to ecological corridors, the more increasing the mammal using rate of ecological corridor(r=0.71, p<0.05). Therefore, the area of green space connected to the ecological corridors that is associated with rate of wildlife using corridors should be considered as a priority when developing an urban ecological corridors. In the future, this study will extend the observation period of the ecological corridors and continuously accumulate data by adding the number of observation cameras. Furthermore, it is expected that the results of this study can be used as basic data for the standards for urban ecological corridors installation.

• 대한토목학회논문집
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• 제39권1호
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• pp.33-44
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• 2019

최근 기후변화 현실화로 강우 발생 시기와 패턴이 변화하면서 유역에 따라 유황이 변화하고 있는 실정이다. 이로 인한 하천 유황의 장기적 변화는 수중생태계의 구조와 기능에 커다란 변화를 야기한다. 하지만 국내에서는 기후변화와의 연계성은 물론, 유량변화와 생태학적 특성을 포함한 수생태계 관점에서의 분석은 대부분 이루어지지 않고 있다. 따라서 본 연구에서는 기후변화로 인한 현재-미래의 유황 변화가 만경강 하도와 홍수터 영역에서 감돌고기의 서식환경에 미치는 영향을 정량적으로 평가하였다. 그 결과, 현재보다 미래에 홍수와 가뭄 등 극한 수문 조건이 심화됨을 확인하였고, 특히 크기, 빈도, 지속시간, 시기와 변화율 등을 비교 분석함으로써 유황 특성의 변화를 명확히 파악하였다. 그리고 유황 특성과 물리서식처 해석을 연계함으로써 기후변화로 인해 미래 생태환경 변동에 대한 위험성이 크게 증대될 것이라는 결과 제시가 가능하였다.