• 한국물환경학회지
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• 제31권3호
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• pp.286-294
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• 2015

Temporal and spatial characteristics of cyanobacterial communities at the monitoring stations for Harmful Algal Bloom Alert System (HABAS) in Nakdong River and Lake Dukdong were investigated for two years (2013 to 2014). A total of 30 cyanobacterial species from 14 genera were found at the survey stations. Microcystis sp. showed maximum cell density in the total cyanobacterial community in August, 2014 at ND-2 and in September, 2013 at ND-3 station. Lynbya limnetica and Geitlerinema sp., non-target species for alert criteria showed maximum cell density at ND-1 (August, 2013) and Dam station of Lake Dukdong (September, 2014), respectively. Total cyanobacterial cell density and the relative abundance of four target genera (Microcystis, Anabaena, Aphanizomenon and Oscillatoria spp.) for alert criteria was relatively lower in the mesotrophic Lake Dukdong than at the eutrophic riverine stations of Nakdong River, indicating cyanobacterial density and the RA of target genera is affected by the trophic state of the monitoring stations. Simulating the alert system using phycocyanin concentration as an alert criterion resulted in the longer period of alert issued compared to the period of alert issued using the current criterion of harmful cyanobacterial cell density due to the influence of phycocyanin concentration from non-target cyanobacterial species.

• 한국지역지리학회지
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• 제22권1호
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• pp.211-224
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• 2016

울진군 울진읍에 위치한 연호(蓮湖)는 기존 동해안의 하천에서 발견되었던 하적호나 석호와는 다른 지형적 특성을 나타내고 있다. 본 연구에서는 울진 연호의 지형적 특성을 분석하고, 이를 통해 그 형성과정에 대해 살펴보고자 하였다. 더 나아가 자연호소와 습지를 지형형성과정에 따라 적합하게 보존하기 위한 연구가 필요함을 주장하였다. 연호의 지형적 특성을 규명하기 위해 1918년도, 1956년도, 2012년도의 지형도를 비교 분석 하였고 남대천과 연호천의 하상종단면도와 기반암 추정선을 그림으로 표현하였다. 또한 남대천과 연호천의 계획홍수위를 통해 침수가능지역을 설정하고 퇴적물의 이동방향과 퇴적환경을 고찰하고자 퇴적물의 입경분포를 분석하였다. 이를 통해 밝혀진 결과들을 종합해볼 때, 연호는 동해안의 하천에서는 연구가 전무했던 '배후습지성 호소'라고 할 수 있다. 따라서 동해안처럼 유로의 길이가 짧고 경사가 급한 하천에서도 배후습지성 호소가 형성될 수 있다고 말 할 수 있다. 또한 배후습지성 호소의 지형적 형성과정과 울진읍의 시가지 발달을 분석하여 그에 적합한 연호의 보존방법을 제언하였다.

• 대한지리학회지
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• 제38권5호
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• pp.701-724
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• 2003

신쟝의 타림분지에 있는 롭노르 호수의 위치와 성격은 19세기 말 이래 내륙아시아에 관심을 가진 많은 학자들(프르제발스키, 리히트호펜, 코즐로프, 헤딘, 헌팅톤, 스타인, 천쫑치 등)의 논쟁 사안이 되어왔다. 그럼에도 20세기 말에 이르러서야 중국과학원 고찰대에 의해 롭노르의 위치와 성격이 해명되었다. 롭노르는 변함 없이 그 자리에 있었고, 그 성격 역시 변함 없이 염호였지만, 그간 위치와 성격에 대해 논란이 있었던 것은 하천수의 유입방향과 수량에 변화가 있었던 것에서 기인한다. 이러한 하천의 변화는 역사시기와 현재 모두에 있어서 롭노르 상류부의 물 사용의 변화에 따른 것이었다. 특히 상류부의 물 사용이 급격히 증가한 1950∼1960년대를 거치면서 롭노르에 물을 공급하는 하천들의 수량이 감소하여 롭노르가 고갈되었고, 하천의 길이마저 축소되는 현상이 발생하였다. 이 시기에 작용한 인위적 작용의 주요 내용이 신쟝 생산건설병단이라는 대규모 조직에 의한 외부 인구의 유입과 이들에 의한 인공 오아시스의 건설이었다. 이러한 토지형질의 변화와 수자원의 고갈은 사막화 문제뿐만 아니라, 사회적 균열마저 야기하고 있다. 나아가 롭노르와 유사한 변화가 중국 서부지역에서 광범위하게 나타나고 있다.

• 대한환경공학회지
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• 제36권5호
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• pp.367-377
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• 2014

국내 최대 상수원인 팔당호는 하천형 호소로 분류되며, 팔당호 수질은 외부오염원의 영향이 크다. 이에 본 연구에서는 팔당호 상류지역의 오염원 분포와 오염물질 유출특성을 분석하여 BOD와 TP 관리를 위한 중점관리 오염원을 선정하고자 하였다. 이를 위해 11개 단위유역에 대한 오염원별 발생부하량과 배출부하량을 조사하고, 74개 소하천의 수질 유량 측정결과를 이용하여 유달부하량과 유역면적당 유달부하 밀도를 분석하였다. 오염원별 BOD, TP 발생부하량과 배출부하량, 유달부하량을 분석한 결과, BOD 발생부하량은 축산계가 66.0%로 가장 높은 비율을 차지하였고, BOD 배출부하량은 생활계가 42.7%를 차지하였으며, BOD 유달부하량은 축산계와 생활계가 각각 36.4%, 34.3%를 차지하는 것으로 나타났다. TP 발생부하량과 배출부하량, 유달부하량 모두 축산계에서 가장 높은 비율을 차지하였으며, 각각 82.5%, 44.4%, 46.7%로 나타났다. 또한 BOD 유달부하밀도는 인구밀도가 높은 경안천 유역이 $14.6kg/km^2/d$으로 가장 높았고, TP 유달부하밀도는 가축사육두수가 많은 청미천 유역이 $1.23kg/km^2/d$이 가장 높게 나타났다. 이러한 연구결과를 통해 팔당호 수질개선을 위해서는 생활오수와 가축분뇨를 중심으로 오염원관리가 필요하며 경안천 유역은 생활오수에 대한 관리가 필요하고 남한강 유역, 특히 청미천 유역은 가축분뇨에 대한 관리가 필요한 것으로 판단되었다.

• 생태와환경
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• 제54권1호
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• pp.1-11
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• 2021

2015년 4월부터 10월까지 남양호 유역의 어류군집 특성을 밝히기 위해 유입하천을 포함한 9개 지점에서 조사하였다. 남양호 유입하천(St. 1~St. 6)에서 27종 5,899개체가 출현하였으며 우점종은 참붕어 Pseudorasbora parva(33.5%)로 나타났다. 남양호 (St. 7~St. 9)에서는 20종 5,672개체가 출현하였으며 우점종은 붕어 Carassius auratus (32.2%)로 나타났다. 남양호 유역에서 츨현한 고유종은 각시붕어 Rhodeus uyekii, 가시납지리 Acanthorhodeus gracilis, 몰개 Squalidus japonicus coreanus, 왜매치 Abbottina springeri, 얼룩동사리 Odontobutis interrupta 5종으로 유입하천에서 전체 출현 종의 18.5%, 남양호에서 15%로 유입하천에서 고유종의 빈도가 높게 나타났다. 외래종은 떡붕어 Carassius cuvieri, 블루길 Lepomis macrochirus, 배스 Micropterus salmoides가 출현하였으며 유입하천에서 전체 출현 종의 7.4% 남양호 15.0%로 호소 내에서의 외래종의 빈도가 높게 나타났다.

• 한국해양학회지
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• 제11권2호
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• pp.64-70
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• 1976

기수호인 화진포에 대한 생태학적인 연구가 여러 차례에 걸쳐 실시된 바 있으나( 홍사오외 1969; 엄규백, 1971, 1973; 전승관 외 1969; 변충규 외 1975) 현생퇴적물에 대한 퇴적환경적 연구는 실시된 바 없다. 따라서 본 연구에서는 화진포의 퇴적물에 대한 조직표준치와 분포 특성 및 호수퇴적물중에 포함된 점토광물의 종류와 호수퇴적물의 화학성분을 퇴적과정의 퇴적요인으로 하여 본 역의 현생퇴적환경특성을 밝히고자 한다.

• 한국환경과학회지
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• 제13권5호
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• pp.479-488
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• 2004

Five sediment cores from the tidal flat of artificial Lake Shihwa are analyzed in terms of sedimentology and geochemistry to evaluate the heavy metal contamination and redox condition of surficial sediment following the Shihwa seawall construction. The variability of concentrations of various elements depends on the depositional environment, and reflects the various redox conditions and sediment provenances. The amounts of Ti and Al and their ratio of Ti/ Al with respect to Li clearly indicate that there is an anthropogenic contribution to the surficial sediment. The high concentrations of heavy metals suggest an anthropogenic contribution at ST. 34 and ST. 22. Concentrations of most elements (Cr, Cu, Zn and Pb) are higher near the Shihwa-Banwol industrial complex than in the central part of Lake Shihwa. Concentrations of heavy metal in surficial sediment near the Shihwa-Banwol industrial complex are two to eight times higher than in the center of Lake Shihwa. Enrichment factors (EF), which are normalized by the unpolluted shale, suggests a significant metallic contamination near the Shihwa-Banwol industrial complex (SBIC). The redox condition is divided into two anoxic and mixed oxi $c_oxic zones based on the carbon:sulfur (C/S) ratios of organic matter and elemental relationships. Correlations among geochemical elements Mn, U and Mo are significantly different from site to site, and may therefore be an indicator of the spatial redox condition. Controlling factors for switching anoxic/oxic conditions are thought to be water depth and the differences in industrial effluent supply. The variations of the Cu/Mn ratio in the sediments confirms above mentioned spatial differences of a redox condition in part, and therefore shows a location-dependence redox condition in sediments at four other sites. The redox condition of the surficial sediment characteristics of the Shihwa Lake are controlled by its geographic location and water depth.th.

• Journal of Ecology and Environment
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• 제33권4호
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• pp.289-298
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• 2010

A number of characteristics of the Lake H$\ddot{o}$vsg$\ddot{o}$l watershed, such as the lake's location at the edge of the Central Asian continuous permafrost zone, provide a unique opportunity to evaluate possible anthropogenic impacts in this remote area in northern Mongolia. In this study, we compared stream solute concentrations in six sub-watersheds in the Lake H$\ddot{o}$vsg$\ddot{o}$l watershed. Water samples were collected during the summer months between 2003 and 2005. Concentrations of $Cl^-$ ranged from 9.8 to $51.3\;{\mu}mol/L$; average nitrate concentrations were very low and ranged from undetectable to $1.1\;{\mu}mol/L$ and average ${SO_4}^{2-}$ concentration at sampling stations with minimal animal grazing ranged from 66 to $294\;{\mu}mol/L$. Average dissolved organic carbon (DOC) concentrations ranged from 642 to $1,180\;{\mu}mol$ C/L. We did not find statistically significant differences in DOC concentrations among the six streams, although DOC concentrations tended to be higher in the two northernmost streams, possibly related to differences in the active layer above the permafrost. Dissolved organic nitrogen (DON) concentrations were correlated with DOC concentration, and followed the same spatial pattern as those for DOC. In streams in this remote watershed, total dissolved nitrogen was made up of mostly organic N, as has been found for other regions distant from anthropogenic N sources. Overall, these results suggest that future research on the dynamics of DOC and DON in this watershed will be especially insightful in helping to understand how changes in climate and land use patterns will affect transformations, retention, and export of dissolved organic matter within these sub-watersheds in the Lake H$\ddot{o}$vsg$\ddot{o}$l region.

• 한국환경과학회지
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• 제11권12호
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• pp.1205-1215
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• 2002

To evaluate the change for water quality after the water gate operation in Shiwha lake, in situ survey were conducted on september in 2000 and January, march, jane in 2001. Chemical characteristics and eutrophication level was estimated from the survey data. The water quality of the Shihwa lake was greatly affected by pollutant load from rainfall, and formation of stratification in summer and winter was increased to effect on nutrient release from sediment. Especially, high concentration of chlorophyll-a was occurred in autumn, due to increased nutrient, high water temperature and low salinity after rainfall runoff. The mean concentration of DIN, DIP were 0.346mg/L, 0.0217mg/L in surface water and 0.826mg/L, 0.0415mg/L in bottom water, respectively, which were over III grade of seawater standard. Also high percentage of ammonia nitrogen to DIN in bottom water for autumn and winter was affected by released nutrient from sediment. Correlation analysis of chlorophyll-a versus TSS was shown that organic matter was affected by autochthonous organic matter stem from the algae, these factor showed reverse correlation about salinity. Closely correlations among to the water quality constituent in continuity survey was appeared. The results of eutrophication index estimation showed the high potentiality of red tide occurrence in Shiwha lake, particularity in summer or fall. Overall water quality was greatly improve to compared with measuring data during 1997~1998 at the beginning water gate operation, which reported by KORDI. Therefore, to improve of water quality in Shiwha lake, we need to establish of management plan about nutrient release from sediment, rainfall runoff, maximum of seawater exchange.

• 한국환경독성학회:학술대회논문집
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• 한국환경독성학회 2003년도 추계국제학술대회
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• pp.27-27
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• 2003

Lake Texoma is located on the border of southern Oklahoma and northern Texas. It has 93,000 surface acres, and is a focus of the recreation, and farming industries in the region. There are potential stressors around the Lake Texoma watershed that may cause adverse ecological effects in the lake. System assimilative capacity (SAC) is the ability of abiotic and biotic processes to atteuniate the stressors. SAC Exceeded indicates potential of occuring adverse eco-effects. A number of representative chemical release sites and stressor sources in the surrounding watershed were characterized, and several impact sites having stressors sources, such as being near agriculture, landfills, housing areas, oil production fields and heavy use recreational activity, were selected for surface water, sediment, and groundwater monitoring. A paired reference site, having similar physical characteristics as its impact site, was also chosen based on its proximity to the impact site. Lake water samples were collected at locations identified as marina entrance, gasoline filling station, and boat dock at five marinas selected on Lake Texoma from September 1999 to December 2001. Paired water and sediment samples were also collected. Groundwater samples were collected at about 70 producing monitoring wells. Water quality parameters measured were inorganics (nitrate, nitrite, orthophosphate, ammonia, sulfate, and chloride), dissolved methane, total organic carbon (TOC) (or DOC), volatile organic compounds (VOCs) such as methyl tert-butyl ether (MTBE) and BTEX, and a suite of metals. Biotic communities were evaluated at impact and reference sites. Five basic components were measured; two terrestirial components (plants and bird comminitires) and three aquatic components (benthic inverbrates, litteral-zone fishes, ecosystem attribures). Potential impacts to these comminites were evaluated.