• Environmental Analysis Health and Toxicology
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• v.24 no.3
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• pp.241-249
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• 2009

Heavy metal contaminants on the aquatic environment are of interest because they can have severe effects on economy and public health. Recently, the studies for monitoring of heavy metals try to do on aquatic system to assess safety and health of ecosystem by heavy metals. Thus, biological responses were investigated on Korean fairy shrimp Branchinella kugenumaensis exposed to cadmium (Cd) or copper (Cu) for long-periods (30 days). The survival rate decreased significantly (p<0.05) on B. kugenumaensis exposed to Cd and Cu at all concentrations. Especially, the highest decrease was observed at the relatively high concentration of Cd and Cu (p<0.01) and the response by Cd exposure was at dose-dependent. The growth rates were also decreased significantly (p<0.05) on B. kugenumaensis exposed to Cd and Cu for at all concentrations. Then, the reproduction rate, numbering cyst, was decreased significantly (p<0.01) on B. kugenumaensis after Cd or Cu exposures. Long exposure of the relatively high concentration Cd and Cu can have severe effects on the reproduction, while exposures of Cd and Cu can not have effects on sex ratios of B. kugenumaensis. Additionally, asymmetric telson deformity was only observed after Cd exposure. Therefore, these results suggest that B. kugenumaensis is a sensitive bio-indicator of heavy metal exposure and these biological responses of B. kugenumaensis give important information for long-term monitoring on aquatic ecosystem.

• Environmental Analysis Health and Toxicology
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• v.21 no.2 s.53
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• pp.185-195
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• 2006

환경오염물질로부터 수생태계 보호를 위한 표준적인 평가 및 관리 수단인 수질환경기준은 오염물질의 독성작용이 일어나는 표적기관에서의 오염물질의 농도에 대한 대체측정치로서 환경 내 오염물질의 농도를 이용해 왔다. 이러한 '외부환경농도에 기반한 접근방법'은 표적기관에서의 독성물질의 농도가 생물체내 농도에 비례하고, 결국 외부환경농도에도 비례할 것이라고 가정한다. 따라서 환경오염물질의 생물이용도나 생물축적 양상의 차이 때문에 고유 독성치를 비교 평가하는데 한계가 있다. 이와 달리 '생물체내 농도에 기반한 접근방법(이하 생체잔류량 접근법)'은 환경오염물질의 생물이용도나 종 특이적 생물축적 양상과 관련된 불확실성을 제거하고, 환경오염물질 고유의 독성을 비교 평가할 수 있게 해준다. 특히 생체잔류량 접근법을 독성동태학 및 독성역학 모델과 함께 사용하는 경우는 실제 현장에서 일어나는 복잡한 노출조건에서의 독성영향을 예측하는데 활용할 수 있다. '생체잔류량 접근법'은 독성기작별 임계잔류량(Critical Body Residue)을 결정함으로써 생물모니터링의 결과를 해석하는데 적용되고 있다. 또한 생태위해성평가를 위해서 필요한 '무영향예측농도(Predicted No-effect Concentration, PNEC)를 예측하기 위한 방법으로 생체 내 잔류량에 기반해서 농도-시간-반응관계를 기술하고, 예측할 수 있는 새로운 유형의 독성역학 및 독성동태학 모델을 제시하고, 생체내 '무영향농도(No Effect Concentration, NEC)'를 추정하게 해 준다. 특히 생체내 NEC는 '무영향관찰농도(No Observed Effect Concentration, NOEC)'와 '영향농도(Effect Concentration, EC)'처럼 분산분석이나 회귀분석모델과 같은 통계적 모델에 기반해서, 농도-반응관계만을 기술할 뿐인 기존 독성모델을 대체할 대안으로 최근에 OECD와 ISO에 의해서 추천되었다.분석을 시행한 결과 인지기능 장애정도 및 MMSEK 점수 증가에 따른 사망위험도는 어느 모형에서도 인지기능 장애정도가 사망에 미치는 위험도는 통계적으로 유의하지 않았다(표 6, 표 7). 이상 본 연구는 농촌지역 노인들에서 인지기능 장애정도가 사망에 미치는 영향을 알아보고자 하였지만, 인지기능 장애정도가 사망에 미치는 영향을 통계적으로 유의하게 고찰하지 못하였다.의한 차이를 보였다. (P<0.05, P<0.001) 5. Excelco로 부식처리된 도재가 5% HF 용액으로 부식처리된 도재보다 부식정도가 더 현저하였다.은 제언을 하고자 한다. 먼저, 학교급식에 대한 식단 작성 시 학생들이 학교에서 제공되기 원하는 식단에 대한 의견을 받고 그 의견에 대한 결과를 게시하여 학생들이 제공되기 원하는 식단을 급식 시 제공하여 학생들이 식단선택에 동참할 수 있는 기회를 주는 것이 바람직하겠다. 또한 영양사는 학급의 반대표와의 정기적인 모임을 가짐으로서 학생들의 불만사항 및 개선 요구사항에대해 서로 의견을 교환하여 설문지조사가 아닌 직접적인 대화를 하여 문제점을 파악하고자 하는 적극적인 자세가 필요하겠다. 특히 아침식사의 결식 빈도가 높았고 이는 급식성과에 부정적인 영향을 줄 뿐 아니라 학교에서 제공하는 음식의 섭취정도에도 영향을 주고 있으므로 학생들에게 학부모와 전담교사 및 학교영양사는 학생들에게 이상적인 아침식사에 대한 교육은 물론이고 아침식사를 실천할 수 있도록 다양한 방안에 대해 함께 연구해야 하겠다. 정부차원에서 학교급식에 아침식사 프로그램을 도입할 수 있는 방안을 연구하고, 아침을 결식하는 학생이 학교에서 수업시작 하기 전에 간단한 식사를 할 수 있는 정책 도입이 필요하다acid의 생성량(生成量)을 측정(測定)하였는데 periodate의 소비량(消費量)은 1.23 mole, formic acid의 생성량(生成量)은 0.78 mole이다.한 경우도 비교적 많이 먹고 있었다(24.3%). 남 여

• Journal of Korean Society on Water Environment
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• v.32 no.1
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• pp.30-35
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• 2016

Urban areas generate large amounts of stormwater and non-point source (NPS) pollutants during rainfall events. These are caused by various land use runoffs, vehicular and human activities and increased impervious cover. The increased runoff and NPS pollutants cause water quality deterioration in the receiving waters and adversely affect the aqua-ecosystem. These environmental impacts could be reduced through the application of low impact development (LID) techniques. In Korea, more than 80% of the total rainfall occurs in summer and most of these were 10 mm or less. Therefore, if the LIDs developed were able to cope with rainfall of 10 mm and below, NPS management could be efficiently conducted. This research was performed to determine the effect of varying amounts of rainfall on the performance capability of an established infiltration and filtration facility (IF facility) that can be applied to Korea's common rainfall ranges. The IF facility area was 1.75% of the catchment area, however the facility treated more than 40% and 60% runoff volume and pollutant reduction respectively for a 10 mm rainfall. Lastly, higher volume and pollutant reduction could be attained when the LID area was at least 2% of the entire catchment.

• Proceedings of the Korea Water Resources Association Conference
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• 2008.05a
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• pp.454-459
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• 2008

하천의 건강성을 유지하고 수환경의 정상적인 기능을 회복하기 위해서는 수서생물들에게 알맞은 서식환경 조성, 점오염원 및 비점오염원 차단, 적절한 유량과 같은 다양한 조건이 요구된다(Gore 1895; Gore et al. 1989). 이 중 유량은 수생태계를 이루는 물리적, 화학적, 생물학적 요소들 가운데 기본이 된다고 할 수 있다(Bunn and Arthington 2002; Nilsson and Svedmark 2002; Arthington et al. 2006). 국내 하천관리를 위한 하천유지유량의 산정에서 고려하고 있는 갈수량, 하천생태계, 하천수질 등 8가지 항목 가운데 최근 생태계와 환경에 대한 사회적 국민적 관심이 증가하면서 하천생태계를 고려한 환경유량의 중요성이 부각되었으나, 현실적으로 생태계를 고려한 정량적 조사자료 구축 및 환경유량산정 등의 객관적 자료는 미흡한 실정이다. 특히, 과거 해당수계 및 하천의 어류분포 현황 파악을 중심으로 이루어진 어류조사는 환경유량 산정 시 기초자료로 활용하거나 직 간접적으로 어류상이 변화하는 원인을 분석하는 자료로 활용하기에는 객관성이 결여되어 있다고 할 수 있다. 어류모니터링 기법 확립은 환경유량산정에 있어 요구되는 정량화와 자료의 객관성을 높이기 위한 작업으로 문헌조사와 청문조사를 포함한 사전조사, 현장조사, 조사결과 정리, 고찰 등의 총 4가지 과정을 기본으로 실시하는 것으로 정하였다(그림. 1), 청문조사와 문헌조사 등의 사전조사를 통해 기존자료를 확보하고 현장의 답사, 조사구간, 방법, 시기 등의 선정을 통해 두 번째 단계인 현장조사의 효율성을 높였다. 현장조사에서는 어류분포 현황 외에도 해당지점의 하상재료, 식생, 유속, 수심, 수질 등 조사지점의 수 환경요소 전반을 기록하여 어류의 서식과 물리 화학적 수환경과의 상호관계를 파악하고자 하였다. 마지막으로 고찰단계에서는 조사 대상 지역 전반적인 어류상 특징과 함께 보호종, 한국고유종, 외래도입종 출현유무 및 빈도, 물리적, 화학적 수환경의 특징, 수환경에 따른 어류상 특징 등의 분석과 함께 조사하천의 건강성을 평가하고자 하였다. 본 연구는 어류모니터링 기법 확립을 통해 환경유량산정 시 요구되는 객관적 기초자료를 구축하고 나아가 오염물질 유입, 하천정비사업 등의 각종 교란요인에 의해 발생할 수 있는 문제점들에 능등적으로 대처하고 교란에 의해 악화된 수환경의 복원을 위해 요구되는 객관적 기초자료 생산에 목적이 있다.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.17 no.3
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• pp.160-180
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• 2012

We have studied the eukaryotic plankton species diversity to compare the community structure of fresh and brackish waters in the lower reaches of the Nakdong River using metagenomic methods. We constructed 18S rDNA clone libraries of total DNAs extracted from environmental water samples collected at Mulgeum (MG100929, fresh) and Eulsukdo bridge (ES, brackish). Through the steps of colony PCR, PCR-RFLP, sequencing and similarity analysis, we discovered the diverse species composition of eukaryotic plankton. Total 338 clones (170 at MG100929 and 168 at ES) were analyzed, and then we found 74 phylotypes (49 for MG100929 and 25 for ES). From the phylogenetic analysis, we confirmed various eukaryotic plankton of broad range of taxonomic groups, including Stramenopiles, Cryptophyta, Viridiplantae, Alveolata, Rhizaria, Metazoa, and Fungi. We also found several unreported species in Korea and candidates of new taxonomic entities at levels higher than genus. Especially, the cryptic species diversity including unreported phylotypes of Pirsonia (Stramenopiles) and Perkinsea (Alveolata) suggests that the molecular monitoring method can produce new informative biological data in monitoring the changes in the Nakdong River Mouth ecosystem.

• Korean Journal of Ecology and Environment
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• v.47 no.2
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• pp.127-134
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• 2014

Organic carbon and nitrogen stable isotope ratios of particulate organic matter (POM) were determined at 7 stations (6 stations in Han river and Paldang dam outflow station) from May to October 2013, in order to understand the origin of POM at the Han river. ${\delta}^{13}C$ values of POM in four stations showed significant seasonal changes season, but ${\delta}^{15}N$ values were enriched in around Kyeongan stream (K). POC, PN and Chl-a concentration showed a similar seasonal pattern in Kyeongan stream, with an apparent decrease from July to August. POC and PN concentration has a higher correlation with Chl-a concentration in Kyeongan stream (K). ${\delta}^{13}C$ and ${\delta}^{15}N$ values of POM has a lighter value during lower Chl-a concentration peroid, compared to other seasons. Our results revealed that Kyeongan stream (K) seemed to be influenced by substantial amount of organic manure or fertilizer input in 2013, compared to the previous year (2012). These results suggest that the analysis of stable isotope ratios is a simple but useful tool for the identification of organic matter origin in aquatic environments.

• Korean Journal of Ecology and Environment
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• v.41 no.3
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• pp.275-282
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• 2008

Water hardness is a significant parameter as related to aquatic toxicity of some heavy metals. Hardness dependent metals include cadmium, copper, chromium (III), nickel, lead, zinc and silver. Developed countries have applied the hardness correction procedure to derive the water quality criteria for protecting the aquatic organisms. In the present study, we investigated the hardness correction algorithms used in United States of America, European Union, Australia/New Zealand, and Canada, and analyzed the details associated with those algorithms. Toxicity values of heavy metals were definitely different after hardness correction for all of algorithms analyzed. We found that the hardness corrected toxicity values followed by the algorithms of USA and Australia/New Zealand were very similar or same, however they were slightly different for cadmium at the hardness less than 30 mg $CaCO_3\;L^{-1}$. Among the hardness correction algorithms studied, the algorithm used in Australia/New Zealand appears to be a good choice to apply in Korean situation due to its simplicity compared to the algorithm of USA.

• Korean Journal of Ecology and Environment
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• v.53 no.2
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• pp.165-172
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• 2020

Heavy metals are common pollutants in the freshwater environment and have toxicological effect in habitat organisms. The heavy metals highly accumulated in sediment and organism, and observed various physiological responses. In this study, we investigated the molecular response to heavy metal toxicity (Al, Aluminum; Cr, Chromium; Cu, copper; Mn, Manganese; Zn, Zinc) through expression of heat shock protein 40, 70, 90 (HSP40, 70, 90), cytochrome 450 (CYP450), Glutathione S-transferase (GST) and Serine-type endopeptidase (SP). HSPs showed up-regulation in Cu and Zn exposures. Furthermore, HSPs expression in treated groups tended to be higher than the control group. The tendency of CYP450 and GST mRNA expression was higher for Cr and Cu than for other exposure group. The expression of SP gene was low at Al exposure and other group were measured to be similar to control. These results suggest that heavy metal toxicity in freshwater ecosystem may affect physiological and molecular process. Also, the comprehensive gene expression in the aquatic midge Chironomus riparius give useful information to potential molecular biomarkers for assessing heavy metal toxicity.

• Korean Journal of Ecology and Environment
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• v.53 no.2
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• pp.173-184
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• 2020

Irrigation ponds, 'dumbeong', which are artificially constructed water resources for traditional farming, serve as a biological shelter connecting seasonally created rice paddy fields to local freshwater ecosystems. This 2018 study surveyed 143 irrigation ponds in the western Civilian Control Zone (CCZ) area from August to September, revealing species diversity and community characteristics of benthic macroinvertebrates. A total of 13,454 individuals of macroinvertebrates were captured and classified into 3 phyla, 5 classes, 17 orders, 59 families, 192 species. Among Insecta, the most frequently recorded order was Odonata, 55 spp.(33.7%), followed by Coleoptera, 52 spp. (31.9%), Hemiptera, 34 spp. (20.8%), Diptera, 17 spp. (9.8%), Ephemeroptera, 3 spp. (2.4%), Trichoptera, 1 spp. (0.6%) and Lepidoptera, 1 spp. (0.6%). Taxon of non-Insecta consisted of Mollusca, 14 spp. (48.2%), Annelida, 11 spp. (37.9%) and Arthropoda, 4 spp. (3.4%). The analysis of Diversity Index (H'), Species Richness Index (RI), Dominance Index (DI) and Evenness Index (J') revealed the general stability of communities in the study sites. A total of 28 rare species were found in 98 study sites, including three endangered species designated by the Ministry of Environment. These results showed that the species diversity and rarity of macroinvertebrates in the study area were greater than those of previous research on lentic wetlands (lake, etc.) and national conserved wetlands(Upo-swamp, etc.) in Korea. A conservation planning of aquatic ecosystems in the western CCZ area, therefore, should focus on conservation of irrigation ponds.

• Korean Journal of Environmental Biology
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• v.37 no.2
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• pp.204-216
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• 2019

To evaluate the biological integrity of aquatic ecosystems, we developed Korean multimetric diatom index (KMDI) using metrics that many researchers have been previously described, and compared to single-metric diatom index such as trophic diatom index (TDI) and diatom assemblage index to organic pollution (DAIpo). For the biological and environmental data, we investigated the epilithic diatoms, water quality and the land-use for 923 sites in Korean streams between 2013-2017, and estuaries between 2010-2017, respectively. Five appropriate metrics were selected according to the following steps; 1) extraction of 300 potential metrics (biological, chemical, physical, and geographical) based on previous references, of these, 2) 46 samples having high separation power were selected, 3) the selected metrics were each tested for variability, redundancy, and sensitivity to the environments, finally 4) construction of multi-metric diatom index comprising single type metrics such as TDI, DAIpo, % motile diatoms, % Achnanthes / (Achnanthes+Navicula), and % number of Gomphonema species. The biological integrity of the 233 sites from the Geum River basin were independently investigated using KMDI. Collectively, the new KMDI showed high sensitivity and explanatory power for environmental factors such as land-use, biochemical oxygen demand, total nitrogen, and electric conductivity. However, it had slightly higher biological integrity for the same sites as compared to single type diatom metrics. Finally, more data accumulation from all over Korea and the development of acceptable diatom metrics were required.