• Korean Journal of Environmental Biology
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• v.31 no.4
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• pp.275-287
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• 2013

The Japanese anchovy Engraulis japonicus is a widespread species in the western North Pacific and major fishery resource. To understand the spatio-temporal variation of anchovy prey items in the coastal waters of southern Korea, the stomach contents of anchovy and the structure of the zooplankton community were analysed at three sites (Jindo, Yeosu and Tong-yeong) from July 2011 to February 2012. The main prey items in Yeosu and Jindo were cyprid stage of barnacle (>35%) and copepod Calanus sinicus (>22%) in July, respectively, while, predominant ones in Tongyeong were small copepods, Paracalanus parvus s.l. (41%) and Corycaeus affinis (22%). During this period, the dominant zooplankton were cladoceran Evadne tergestina (39%) in Yeosu, small copepod, P. parvus s.l. (28%) in Jindo and cladoceran E. tergestina (14%) in Tongyeong. The dominant prey items were barnacle larvae and copepods in summer, phytoplankton and Pseudodiaptomus marinus in autumn and P. parvus s.l. and cold water copepod, Centropages abdominalis in winter. Anchovy prefer the prey item C. sinicus (3%) over E. tergestina (39%), which was a dominant species in the catching site in summer. P. marinus (0.5%) and C. abdominalis (0.9%) were preferred over P. parvus s.l. (30%, 21%) in autumn and winter, respectively. Prey items varied with area and season in the coastal waters of southern Korea. These results suggest that the prey selectivity of anchovy showed high flexibility and adaptability in the study waters.

• Korean Journal of Ecology and Environment
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• v.49 no.4
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• pp.296-307
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• 2016

Ecological restoration is an eco-technology, which heals the nature damaged by human activity by imitating organization and function of the integrate nature and thereby provide an inhabitable space for diverse organisms. Such an ecological restoration has to be carried out by applying restoration plan prepared based on the results of diagnostic evaluation discussed in the diversified respects. This study aims to prepare an ecological restoration plan of the damaged forest ecosystem in Mt. Moodeung National Park. To arrive at the goal, first of all, we diagnosed quality of forest landscape established in Mt. Moodeung National Park based on natural (topography, climate, and distribution of vegetation) and artificial (land use, linear landscape element) factors. In addition, we evaluated the integrity of each zone divided by linear landscape element quantitatively based on geometric property and land use intensity. As the result of analysis, topography of Mt. Moodeung National Park tended to be depended on weathering property of parent rock and vegetation zones were divided to three vegetation zones. Based on land use pattern, deciduous broad-leaved forest, evergreen needle-leaved forest, and mixed forest occupied about 90% of Mt. Moodeung National Park. Mean score of forest landscape quality was shown in $69.86{\pm}11.41$. As a result, forest landscape elements in Mt. Moodeung National Park were influenced greatly by human activity and the degree was depended on topographic condition. This study suggested the synthetic restoration plan to improve ecological quality of Mt. Moodeung National Park based on the results of diagnostic evaluation.

• Korean Journal of Ecology and Environment
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• v.55 no.1
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• pp.1-9
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• 2022

An estuary is an area where a freshwater river or stream meets the ocean. Even before the importance of the value of estuaries was recognized, the estuary was lost because of large-scale conversion by draining, filling, damming, and dredging. In South Korea, 643 estuaries are located, and the total area is 3,248,300 ha, accounting for 32.5% of the total area of South Korea. Over 35% of Korean estuaries are closed estuaries which are only temporally connected with the sea, either permanently or periodically. Since 2008, in order to preserve the estuary ecosystem and solve major issues in the estuary by accumulating knowledge about the estuarine ecosystem, the Ministry of Environment of Republic of Korea has been conducting the "Estuarine Ecosystem Monitoring and Assessment Project". At 668 sites of 325 estuaries, epilithic diatom, benthic macroinvertebrate, fish, and vegetation are investigated, and the habitat condition of each site is evaluated using the newly developed biotic index. More than 100 researchers annually record 2,097 species of estuaries according to the standardized survey guidelines over the past 14 years and provide strictly managed data necessary for establishing estuaries conservation policies. As a result of bibliometric analysis of 1,195 research articles related to the monitoring and assessment of the estuarine ecosystem, research on pollutants such as heavy metals and sediment control have recently been conducted. "Estuarine Ecosystem Monitoring and Assessment Project" is an ecological monitoring type of long-term mandated monitoring that is usually focused on identifying trends. Although it is difficult to identify the mechanism influencing a change in an ecosystem through long-term mandated monitoring, providing empirical data for supporting evidence-based policy, decision-making, and the management of ecosystems. In order to increase the efficiency of the project, research to investigate the relationship between sediments and pollutants and organisms can be conducted at specific estuaries or sites to compensate for the shortcomings of mandatory monitoring.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.245-245
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• 2010

우리나라 생활폐기물 중 음식물쓰레기는 가장 많은 부분을 차지하고 있다. 또한, 음식물쓰레기에서 발생되는 음폐수의 발생량은 8,926톤/일에 달하고 있지만, 이 중 극히 일부만이 하수처리장 등에서 병합 처리되고 있고 대부분은 해양 투기되고 있는 실정이다. 이에 본 연구에서는 독일 GBU사로부터 중온/습식/이상 혐기성 소화 기술을 도입하여 HADS Pilot Plant를 설치하였고, 2008년 3월부터 국내 음폐수 및 음식물쓰레기에 적합한 최적의 운전기술을 확보하기 위한 Pilot Test를 실시하였다. 본 실험에 사용된 HADS Pilot Plant는 산발효조($6m^3$), 메탄발효조($50m^3$), 안정화조/가스저장조($40m^3$)그리고 가스 소각기로 구성되어 있다. 그리고 적용 음폐수 및 음식물쓰레기는 경기도 Y군에 위치한 사료화 시설에 반입되는 것을 이용하였는데 음폐수는 평균 TS 13.5%, VS 80%, pH $3.7{\pm}0.2$의 성상을 나타내었다. 이를 이용해 계단식으로 유기물 부하를 증가시키면서 $4kgVS/m^3/d$까지 적용하며 중온 상태에서 혐기성 소화를 실시한 결과, $0.8Nm^3/kgVS_{rem}/d$의 바이오가스 회수 및 85%의 VS 감량이 가능함을 확인하였다. 그리고 음식물쓰레기는 음폐수와 달리 1차 파쇄/선별기 및 배관상에 설치되는 2차 미세파쇄/선별기를 통한 전처리를 실시하였고, 1차 파쇄/선별 후 평균적으로 TS가 17.4%, VS는 81%, pH는 $3.85{\pm}0.2$의 성상을 나타내는 음식물쓰레기를 2차 미세파쇄/선별기를 거쳐 Pilot Plant의 산발효조에 투입하여 중온상태에서 혐기성 소화를 실시하였다. 음폐수 적용시와 마찬가지로 계단식으로 유기물 부하를 증량하면서 $4kgVS/m^3/d$까지 적용하여 운전하였고, 그 결과 약 $0.9{\sim}1.2Nm^3/kgVS_{rem}/d$의 바이오가스 회수와 85~87%의 VS 감량 효율을 확인하였다. 음폐수와 음식물쓰레기의 혐기성 소화 실험 결과, 제거된 VS량을 기준으로 보았을 때, 음식물쓰레기에서 더 많은 바이오가스 발생하였는데 이는 음식물쓰레기에 존재하는 고형물이 미생물들의 서식 공간으로 활용됨에 따라 혐기성 소화 과정에서 일어나는 혼합 발효 및 공영양 대사가 음폐수 대비 좀 더 수월하게 일어날 수 있게 된 데에 따른 결과라고 생각된다. 당사의 HADS Pilot Plant test에서는 계단식의 순차적인 유기물 부하 증량과 총VFA/총 알카리도 비율을 0.3~0.4 수준이하로 유지하며 운전함에 따라 음폐수와 음식물 모두에서 안정적으로 $4kgVS/m^3/d$까지의 유기물 부하 적용이 가능하였다. 또한, 생산된 바이오가스 내 메탄의 함량은 60~65%를 유지하였으며, 메탄발효조의 pH는 별도의 조절이 없이도 운전기간 동안 평균 7.8~7.9 수준을 유지하였다. 이처럼 pH 3.7~3.8의 음폐수 또는 음식물쓰레기의 투입에도 안정적인 완충능력을 보여준 것은 소화조 내에서 기질로부터 분해되어져 나오는 암모니아와 이산화탄소가 강력한 버퍼 시스템을 구축하고 있음에 따른 결과로 사료된다. 그리고 음폐수와 음식물쓰레기의 경우 모두 85%이상의 높은 VS 제거율을 보여주었는데 이는 당사의 HADS Pilot Plant 소화조의 구조가 내통과 외통으로 구분되어져 있음에 따라 plug flow + CSTR의 특징을 가짐에 따른 결과로 판단된다. 상기한 결과를 바탕으로 향후에는 $5kgVS/m^3/d$ 수준의 유기물 부하 적용운전도 계획하고 있다.

• Journal of Wetlands Research
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• v.18 no.4
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• pp.378-385
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• 2016

This study aims to suggest the framework of functional assessment on lotic area based on HGM(Hydrogeomorphic) approach targeting Wetland Protected Areas which are in the type of river channel, and to set up the fundamental data as a reference wetland. A total of 10 factors in terms of hydrology, biogeochemistry, plant habitat and animal habitat was analyzed based on the original approach of HGM and each Functional Capacity Index(FCI) of those factors was calculated. As the result of the modified FCI analysis, Damyang riverine wetland which is with artificial river bank had high values in the variables of area ratio of actual vegetation in the foreland, the number of plant per area and the area ratio of Salix spp., and those values were highly reflected on the factors of Nutrient Cycling(947,668.00), Species Richness and Maintain Characteristic Plant Communites(6.39) and Maintain Spatial Structure of Habitat(11.00). The Hanbando wetland which is keeping the natural bank had higher values in the variables of structural scale and species diversity, and the those values were highly reflected on the factors of Energy Dissipation(17,805.16), Subsurface Storage of Water(0.54), Removal of Imported Elements and Compounds(103,052.73), Maintain Characteristic Detrital Biomass(2.31), Maintenance of Interspersion and Connectivity (6.50), Species Diversity of Benthic macro-invertebrates(1.60) and Species Diversity of Vertebrate & Species Number of Other Animals(2.52/ 151.50), compared to the Damyang Riverine Wetland.

• Journal of Wetlands Research
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• v.21 no.spc
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• pp.1-8
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• 2019

River works for water utilization have substantially altered the natural flow regime, and it has resulted in deformation of healthy river ecosystems. In Korea, river restoration projects have conducted actively since 1990's. Major purposes of the river restoration are the rehabilitation of modified river channel, improvement of water quality, and creation of aquatic habitats as well as recreational spaces using natural material for river work. However, there have been little interests about the restoration of flow regime which influences to most aspects of river ecosystems. The restoration of natural flow regime has received much attention in preservation of aquatic ecosystems. It should be needed to explore the relationship between flow regime and river ecosystems, and the restoring flow regime is essential. This paper introduce the concept of environmental flow through the interrelation between flow regime and river ecosystem. It provides rolls of flow regime and addresses the method of establishing target flow regime using the RVA(Range of Variability Approach) that suggested by Richter et al.(1997) through analysis of altered flow pattern case of Han river basin.

• Proceedings of the Korea Water Resources Association Conference
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• 2009.05a
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• pp.496-500
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• 2009

소하천은 하천 네트워크의 최상류에 넓게 소재하는 하천이다. 본 연구의 목적은 올바른 소하천 수생태계 관리방안을 도출하기 위하여 소하천의 건강성을 분석하고 현행 소하천 관리제도의 개선점을 모색하는 것이었다. 본 연구에서는 다음과 같은 분석방법을 이용하였다. 첫째, 2007년 한강수계 소하천 28개 지점에서의 부착조류($DAI_{PO}$, TDI), 저서성 대형무척추동물(KSI), 어류(IBI), 서식환경, 수변환경 등 6개 항목에 대한 수생태 건강성 조사결과를 토대로 공간적 분포와 수질현황을 조사하여 소하천에 대한 종합적인 건강성 평가를 실시하였다. 둘째, 분석대상지역을 각각 소하천 구간스케일(28개 지점)과 유역스케일(팔당호, 안성천 유역)로 선정, 하천차수도(1:25,000)를 활용하여 해당 구간과 유역의 소하천도를 작성하였다. 셋째, 작성된 소하천도 는ArcGIS(ver. 9.3)에서 30, 60, 90, 120, 150-m Buffering을 하였다. 다음으로 소하천 구간은 중분류(23개 항목, $2000{\sim}2006$ 또는 2007년) 토지피복도를, 팔당호 및 안성천 유역의 소하천은 대분류(8개 항목, $1975{\sim}2000$년) 토지피복도를 적용하여 분류항목별 면적변화비율을 산정하였다. 끝으로 소하천 정비에 대한 제도적 문제점을 분석하여 소하천 관리의 개선점을 연구하였다. 그 연구 결과, 첫째 연구대상 소하천(28개)의 건강성은 도심 소하천에서 가장 낮게 조사되었고, 일부 소하천은 비록 상류에 위치함에도 불구하고 부착조류의 유기물, 영양염류 평가가 낮게 평가되었다. 둘째, 소하천 구간 스케일의 수변토지피복변화 분석결과 소하천 수생태 건강성은 거시적으로 산림, 도시화, 밭 등의 피복변화에 민감한 것으로 나타났으며 도시화 피복변화의 영향은 수변 30m에서 60m보다 3배 정도 큰 것으로 나타났다. 유역 스케일 분석에서는 상대적으로 도시화가 많이 진행된 안성천 유역의 소하천이 팔당호 유역보다 낮은 건강성일 것으로 예측되었다. 결론적으로 적절한 소하천 수변관리는 지역 하천의 건강성을 온전히 회복시키고 개선 유지하기 위한 중요한 수단들 중에 하나이며 수변토지피복의 변화율은 (소)하천 건강성 또는 유역관리의 지표로 활용될 수가 있는 것으로 조사되었다. 이와 더불어 본 연구를 통해 소하천 복원 및 관리는 소하천 특성을 고려한 장기적인 계획과 관리대상의 우선순위를 바탕으로 점진적인 대안마련이 필요할 것으로 사료된다.

• Ocean and Polar Research
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• v.27 no.3
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• pp.299-309
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• 2005

The community structure of meiobenthos was studied in the sediment of Kongfjorden, Spitsbergen of Svalbard Island in the Arctic Sea. Samples of meiobenthos were collected in August, 2003. Meiobenthic organisms were collected by SCUBA and van veen grab or acryl sub-corers 34mm in internal diameter, and were taken from upper sediment to a depth of 3cm at each station. A total of 26 meiofaunal groups were found in the sediment of Spitsbergen in Svalbard Island. Nematodes were the most dominant faunal group. Sarcomastigophorans, benthic harpacticoids, and nauplius larvae of crustaceans, were also important components of the meiobenthic community of Kongsfjorden. All of these low faunal groups were comprised of more than 90% of total meiobenthos at every station. The total density of meiobenthos at each station was highest at station MeG 6 $(3,583{\pm}1,137inds./10cm^2)$, and lowest at station $MeG9(28{\pm}1inds./10cm^2)$. Meiobenthos in general showed the highest density in the upper 1cm layer. This may be associated with food and oxygen supply to subsurface. Harpacticoids showed extreme preference at the surface and little presence in layers deeper than 2cm. These animals may be less resistant to oxygen deficiency, and nauplius also showed the same trend. However, in St. MeG 8 and 9, meiobenthos were dense at depths of more than 0-1cm, at especially at depths of 2-3m because of relatively easy penetration of oxygen. Based on the results of cluster analysis, three meiobenthos assemblages were distinguished: one was in the outer and two were in the inner fjord. Station SCU 5 was grouped with the meiobenthos assemblage located in the outer fjord. The outer ford community was characterised by : 1) a relatively low mean number of meiobenthos taxa, 2) a relatively high density of harpacticods and nauplius. One of the inner ford communities (a group of four nation: MeG 2, 3, 8, 9) was in the proximity of the glaciers. Specifically, it was characterised by : 1) a low mean number of meiobenthos taxa, 2) a low density. The other inner ford community was characterised by both a high density and great mean number of meiofaunal taxa.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.4
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• pp.640-651
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• 1997

This study was performed to examine the distribution patterns, ecological characteristics and celluar fatty acid compositions of marine bacteria in Suyeong Bay. During study periods, total cell count (TC) and viable cell count (VC) were $10^7-10^8/m\ell\;and\;10^4-10^6\;cfu/m\ell$, respectively. The temporal variations of TC showed similar patterns between surface and bottom layer, but the VC at bottom decreased gradually from winter to summer. Among the 303 bacterial strains isolated in the study area, which belong to 10 genus types, Pseudomonas spp., $(32.3\%)$, Acinetobader sup. $(19.1\%)$, Vibrio spp. $(11.2\%)$, Flovobacterium spp. $(10.6\%)$ and Bacillus spp. $(7.9\%)$ were dominant. Thirty-one fatty acids were detected from Pseudomonas spp. and Bacillus spp., which were the most predominated among Gram positive and Gram negative bacteria. Celluar fatty acid compositions of Bacillus spp. were relatively simple compared to those of Pseudomonas spp.. Relatively high ratio of monounsaturated forms were detected in Pseudomonas spp. while branched types were dominant in those of Bacillus spp.. Hydroxy and cyclopropane fatty acid were detected only in the cellular fatty acid of Pseudomonas spp.. Cellular fatty acid compositions of Pseudomonas spp. revealed relatively high percentage of $C_{16:1},\;C_{17:1},\;C_{18:1}\;and\;C_{16:0}$, While Bacillus spp. predominated $C_{16:0}\;iso\;C_{16:0}\;anteiso,\;C_{17:0}\;anteiso\;and\;C_{16:1}$.

• Journal of the Korean Institute of Landscape Architecture
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• v.36 no.3
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• pp.29-38
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• 2008

This study intends to analyze the value of school forests, one type of urban forest. For this purpose, four attributes of school forests were investigated, considering ecological, educational, social and economic values using a conjoint model as the stated preference. Based on literature reviews, the levels of the four attributes were selected, and a questionnaire survey was given to 279 urban residents divided into 2 groups: those impacted by school forests and those not. The study results suggest that the most important attribute of school forests is economic value, and next is ecological, social and educational value according to the part-worth model. The fitness level of the model is 0.900(total group) which is very significant. As for the economic value, free and 1,000 won are more critical factors than the other 2 levels, 5,000 won and 10,000 won and air pollution purification and making the school landscape are more critical factors than small habitats and microclimate factors. In addition, regarding the social value related to residents' leisure activities，the utility of nature observation is higher than walking and exercising. Finally, for educational value, understanding nature's importance is more critical than the emotions and learning of students. The estimated WTP per household/month is 3,580 won, the group related to school forestsis 3,650 won and the non-related group is 3,540 won. Based on these results, the estimated total economic value of all households per year is 6,820 hundred million won. The group related to school forests is 6,970 hundred million won and the non-related group is 6,750 hundred million won.