• 한국어류학회지
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• 제11권2호
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• pp.172-176
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• 1999

한국 동해안으로 유입하는 형산강, 영덕 오십천, 송천천, 죽산천에 서식하는 미꾸리과 Cobitidae의 한국 고유종인 동방종개 Iksookimia yongdokensis의 핵형을 조사하였다. 그 결과 염색체 수는 100이었고 44 meta-submetacentric, 56 subtelo-telocentric chromosome으로 FN은 144이었다. 이러한 사실로 보아 I. yondokensis는 cobitid fishes의 tetraploid species라고 생각된다.

• 한국조경학회지
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• 제48권1호
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• pp.25-34
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• 2020

유역의 토지이용과 하천에 인접한 수변림은 하천의 수질을 결정하는 중요한 요인이다. 특히 유역의 개발지역은 불투수면을 증가시키고, 강우유출 특성과 비점오염물질 거동을 변화시켜 하천의 수질을 악화시킨다. 한편, 수변림은 다양한 수문학적, 생화학적 및 생태학적 작용을 통해 유역의 토지이용이 수질에 미치는 영향을 완화시키는 것으로 보고되어 왔다. 하천의 수질은 다양한 요인들에 의해 영향을 받기 때문에 요인들 간 인과관계를 이해하는 것이 중요하다. 본 연구는 인과관계를 분석할 수 있는 구조방정식모형을 통해 하천환경 특성, 유역의 개발지역 면적, 수변림의 공간적 구조가 총질소 농도에 미치는 구조적 관계 분석에 목적을 두고 수행되었다. 연구 대상지는 낙동강 대권역으로 선정하였으며, 수질 자료는 2012년 환경부의 「전국 하천 수생태계 현황 조사 및 건강성 평가」 결과를 이용하였다. 환경부의 토지피복도에서 수변림과 개발지역 데이터를 추출하여 SPSS Amos 프로그램을 통해 구조방정식모형을 추정하였다. 모형 추정 결과, 개발지역은 고도에 의해 결정되며 수변림의 공간적 구조는 개발지역 면적에 영향을 받는 것으로 나타났다. 또한, 개발지역 면적은 총질소 농도에 직접적인 영향과 수변림의 공간적 구조를 통해 간접적인 영향을 주는 것으로 나타났다. 특히 개발지역은 수변림의 LDI와 총질소 농도를 증가시키고 LPI와 PLAND를 감소시키며 LDI와 PLAND는 총질소 농도를 감소시키는 것으로 나타났다. 본 연구의 결과는 유역의 개발지역이 하천의 총질소 농도에 직간접적으로 영향을 미치나, 수변림이 공간적으로 안정적인 구조를 갖고 식생이 풍부할 경우, 개발지역이 하천 수질에 미치는 부정적인 영향을 상당히 완화시킬 수 있다는 것을 의미한다. 따라서 중장기적인 유역 관리 계획 수립 시, 하천의 수질 회복을 위해서는 유역의 개발지역 비율을 최소화하는 것이 중요하며, 유역 개발에 의한 하천 수질의 영향을 완화하기 위해서는 수변림의 양과 구조의 복원 및 관리가 필요하다.

• 암석학회지
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• 제25권4호
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• pp.361-372
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• 2016

라하르는 거주 지역 주변의 기반시설의 파괴와 인명 손실을 일으킬 가능성이 있는 격변적인 사건이다. 그러므로 라하르 위험지역의 영역 설정은 매우 중요한 작업이다. 본 연구에서는 Laharz_py 프로그램을 적용하여 한라산 화산체에서 발생 가능한 라하르 영향 지역에 대한 개략적인 예측을 수행하였다. 화산체의 지형구배(H/L비)와 라하르 부피를 시나리오의 영향 변수로 선정하였고, H/L비는 0.20, 0.22, 0.25로, 근위 위험지역 경계로부터 발원 가능한 하천의 하류 방향으로 발생 가능한 라하르 부피는 30,000, 50,000, 70,000, 100,000, 300,000, $500,000m^3$를 적용하여 시나리오를 작성하고, 이에 따라 모의를 진행하였다. 수치 모의 결과에 근거하면, H/L비가 증가함에 따라 근위 위험경계 지역의 면적은 점차 감소하였다. H/L비가 증가함에 따라 라하르 영향 하천의 개수가 줄어드는 경향을 보였다. H/L비 0.20인 경우 제주시 쪽의 3 하천(광령천, 도근천과 한천)과 서귀포시 쪽의 6 하천(궁산천-강정천, 호근천(완제천)), 서홍천(연외천), 동흥천, 보목천 그리고 영천-효돈천), H/L비 0.22인 경우 제주시 쪽의 2 하천(광령천과 한천)과 서귀포시 쪽의 5 하천(궁산천-강정천, 서홍천, 동흥천, 보목천 그리고 영천-효돈천), H/L비 0.25인 경우 제주시 쪽의 2 하천(광령천과 한천)과 서귀포시 쪽의 1 하천(영천-효돈천)이 라하르의 영향을 받는 하천이다. 본 연구의 결과는 한라산에서 발생하는 라하르로 인하여 야기될 수 있는 직접적인 화산재해 피해에 대한 위험등급도를 작성하는 기본 자료로 활용할 수 있을 것이다.

• 한국환경농학회지
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• 제27권2호
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• pp.105-110
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• 2008

본 연구는 한강권역 농업용 소하천 88지점에 대하여 현재의 수질상태를 고려하여 수질등급모형을 구축하고자 실시하였다. 10개의 수질항목에 대하여 각 수질항목별 상위 20%씩 level을 부여한 후, 최저 등급을 기준으로 전체 수질등급을 부여하였는데, Level I에 해당하는 하천은 없었고, Level II는 1지점, Level III은 3지점, Level IV는 22지점, Level V는 62지점으로 조사되어 등급이 낮은 Level V로 갈수록 많은 하천들이 속하였다. 집단간 차이의 유무를 알아보기 위해 집단 평균의 동질성을 검정한 결과, DO, BOD, $COD_{Cr},\;NH_3-N$, 그리고 SS가 집단 간에 차이가 없는 것으로 조사되어 판별분석 시에는 제외되었다. 판별력이 가장 뛰어난 $NO_3-N$가 수질등급에 관여하는 변수로 선택되었으며, 분류함수계수에 의한 각 수질등급별 등급모형은 Level II=$-4.648+3.246{\times}[NO_3-N]$, Level III=$-5.084+3.456{\times}[NO_3-N]$, Level IV=$-4.298+3.067{\times}[NO_3-N]$, Level V=$-7.369+4.396{\times}[NO_3-N]$로 구축되었고, 적합도 평가에 의한 구축된 수질 등급모형의 적합도는 88.4%로 조사되어 높은 적합도를 보였지만, 향후 더 많은 자료의 확보와 축적으로 수질등급모형이 수정, 보완된다면 활용가능성은 더 높을 것으로 판단되며, 이를 바탕으로 각 권역별로도 실제 수질에 적합한 수질등급모형을 구축할 수 있으리라 생각된다.

• 한국환경복원기술학회지
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• 제15권2호
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• pp.19-29
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• 2012

Numerous studies suggested that fish assemblage structure reflects the status of stream ecosystems. The status of streams integrity, including various trophic levels, water quality and habitat degradation, can be assessed by fish assemblages. In this study, we investigated the relationships between fish assemblages and streamline geometry of streams. Previous studies suggested that geomorphologic parameter can be a critical factor of permeability between adjacent two systems. From a landscape ecological perspective, edges may partially control the flow rate of energy between two adjacent systems. Thus, the Streamline geometry can be a geomorphologic parameter that exhibits the integrity of stream. We selected the Nakdong river for study areas, which is one of major rivers and the longest (525 km) River in South Korea. We used the revised IBI representing overall ecological characteristics of Korean fish assemblages and eight sub-assessment criteria of IBI, collected from 82 sampling sites in the Nakdong River. For calculating the Streamline geometry, we measured fractal dimension index that generally used in biology, ecology and landscape ecology. We used the digital land-use/land-cover map and generated a 1-km buffer for each sampling site and refined the shape of the Streamlines. Pearson correlation analyses were performed between Streamline geometry and IBI and sub-assessment criteria of IBI. The results show that IBI and eight sub-assessments of fish are significantly correlated with geometry of Streamline. The fractal dimension of Streamline geometry were related with IBI (r = 0.48) and six sub-assessments of IBI, including total number of native fish and native species, the number of riffle benthic species, sensitive species, tolerant species and native insectivore. Especially, the number of tolerant species(r = -0.52) and native insectivore(r = 0.52) show strong correlation with geometry of Streamline. These results indicate that lower Streamline geometry can result in poor fish assemblages, while higher geometry of Streamline can enhance fish assemblages by potentially supplying insects and better habitat conditions. We expect the results of our study to be useful for stream restoration and management. However, we see the necessity of study investigating the mechanisms how Streamline geometry affect fish assemblages.

• 한국환경과학회지
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• 제23권2호
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• pp.291-302
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• 2014

We have studied characteristics of community structure on the benthic macro-invertebrates at twelve selected sites in upstream, midstream and downstream of Paemsagol, Piagol, Chilseongol and Daeseonggol, major streams of Jirisan Mountain, for three years from April 2008 to September 2010. As a result, 2 phyla, 3 classes, 11 orders, 41 families, 119 species and 4,449 individuals of benthic macro-invertebrates have been collected and classified in this study. Among them EPT group (Ephemeroptera, Plecoptera, Trichoptera), commonly appearing taxa in clean stream ecosystem, was found most frequently. The highest species number of benthic macro-invertebrates were collected in 2008, the year with lower climatic influence including heavy rain. In almost all of survey sites 80% or over of EPT group were counted, and St. 1 scored highest rate of EPT group at 92.59%. Most dominant species was Ecdyonurus kibumensis at 12.83% of dominance index, and subdominant species was Goerodes KUb at 6.81% of dominance index. The investigation of the feeding function group indicated that gathering-collectors were dominant with 26 species and 1,334 individuals, while the number of filtering-collectors was lowest with 11 species and 230 individuals. This result represents that the feeding function group of Jirisan Mountain is mountainous stream-specific one. Both diversity index and richness index were lowest at the midstream of Chilseongol (St. 5), while the midstreams of Daeseonggol (St. 11) and Piagol (St. 8) were highest in diversity and richness indices respectively. The analyses of linear regression and correlation were performed in order to investigate and to predict the appearance aspect of EPT group by altitude. The results showed that the ratio of Plecopteran species number has increased by the elevation of the altitude at 0.05 significance level. Cluster analysis was also carried out for evaluating environmental similarities among survey sites. As a result, upper regions of Paemsagol (St. 1) and Piagol have clustered as most similar sites each other, while the midstream of Piagol (St. 8) has separated with lower similarity value than other sites in species composition.

• 생태와환경
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• 제42권3호
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• pp.303-316
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• 2009

Benthic macroinvertebrate communities collected from eight different streams in South Korea were analyzed to compare community and biological indices across different levels of water pollution. The Self-Organizing Map (SOM) was utilized to provide overview on association of the proposed indices. The sample sites were accordingly clustered according to the gradient of pollution on the SOM. While the general trends of the indices were commonly observable according to different levels of pollution, the detailed differences among the indices were also illustrated on the SOM. The conventional diversity and evenness indices tended to be high even though the water quality state was poor representing relatively weak gradient at polluted sites, while the index presenting the saprobic degree such as family biotic index showed the stronger gradient at the polluted area and was robust to present the gradient. Our results also confirmed the general characterization of two indices: The Shannon index is more strengthened by the number of species occurring at the sample sites, while the Simpson index is more influenced by the degree of evenness among the species. The patterning based on the SOM was efficient in comparatively characterizing the proposed indices to present ecological states and water quality.

• The Korean Journal of Ecology
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• 제19권6호
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• pp.529-541
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• 1996

During the period of December 1992 (winter-spring) and from February 1995 (winter-spring), the leaf processing rates of oak (Quercus serrata) and tulip (Liriodendron tulipifera) tree was investigated in the headwater streams in southeastern part of Korea in conjunction with the distribution pattern of macroinvertebrate fauna. Using two types of bags ($10\times30cm$ with 5 g of dry leaves; open bag with holes, closed bag without holes), decomposition rates of oak and tulip tree by shredder and/or microbiota at a reatively undisturbed 2nd-order stream were compared, Regardless of leaf type, leaves in the open bage decomposed slightly faster than those in the closed bags. In the 1992 experiment, osk leaves decomposed much slower than tulip leaves (after 138 degree days, osk : closed, 0.006% loss/day ; open, 0.008 ; tulip: closed, 0.021 ; open, 0.023; n=2). The of the first experiment using oak leaves in 1995 were similar to those of the first experiment (after 151 degree days, oak: closed, 0.005% loss / day; open, 0.006; n=6). Over 50% of invertebrates from 122 leaf pack samples collected from 12 streams during the winter period of 1994 were identified as shredders (shredder, 56.2; collector, 32.7; scraper, 8.65; predator, 2.45%). Among shredders, Gammarus sp. and Tipula sp. were dominant species in terms of number and biomass (8.2 ind./g, 1.0 ind./g AFDW of leaves). Among many physico-chemical parameters, the width of stream channel was found to be the most influential factor in the distribution of Gammarus and Tipula (Gammarus: r=-0.34, P<0.001;Tipula:r=0.40, P<0.001). Considering the fact that oak is one the dominant riparian vegetation in the southeastern part of korea, the patterns of oak processing and shredder distribution shown in theis study may well represent some of the important characteristics of headwater steams in southeastern Korea.

• 한국환경복원기술학회지
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• 제25권5호
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• pp.77-88
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• 2022

This study aims to understand the relationship between the distribution of fish species in the two water ecosystems and the habitat factors according to the survey period targeting Gwanggyo Lake Park in the city. There are studies on the appearance and distribution of species by applying eDNA to freshwater ecosystems. However, in the domestic, streams are the target, and studies on the relationship between species distribution and habitat environment in two water environments are lacking. We conducted to analyze the species list and relationship with habitat factors using eDNA research in May and October at 21 points in Gwanggyo Lake Park, Suwon City, which were connected to lakes and streams. As a result, there was no species difference in the water environment according to the survey period. However, the total number of reads during the spawning season(May) was 3,126,482, which was more than double that after the spawning season(October). Tolerant species appeared in Woncheon Lake with a slow or stagnant flow, but there was no significant correlation between species and habitat factors depending on the survey period. On the other hand, intermediate and sensitive species appeared in the Woncheon stream with high flow. There was a significant correlation between the low temperature during the spawning season and the high dissolved oxygen content after the spawning season(P<0.001, Tem.: 20.7±2.6℃, DO: 8.6±1.7). It is expected that environmental DNA will be used to survey species and suggest monitoring methods according to the survey period.

• 생태와환경
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• 제40권4호
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• pp.569-575
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• 2007

This study was carried out to determine bioaccumulation levels of total mercury on various fish tissues in two streams (Banseok and Hasin Stream) and one lake (Yeongsan Lake) during April-May 2007. We also determined natural background levels of total mercury bioaccumulation to evaluate relative individual impacts of fish and compared the levels with reference sites as a preliminary study to evaluate heavy metal stressor using fish. For the study, we collected fishes in the sampling sites and analyzed the concentrations of total mercury in the liver, kidney, gill, vertebral column, and muscle tissues using Direct Mercury Analyzer (DMA-80, US EPA Method 7473). The levels varied depending on the types of waterbody and tissues used. Concentrations of total mercury ranged between 5.1${\mu}g$ $kg^{-1}$ and 108.6 ${\mu}g$ $kg^{-1}$ in the streams and between 5.3${\mu}g$ $kg^{-1}$ and 87.3 ${\mu}g$ $kg^{-1}$ in the reservoir, and the values were highest in the muscle tissues. Levels of natural background levels of total mercury, even though the sampling number was few, averaged 23.6 ${\mu}g$ $kg^{-1}$ in the study sites. The individual and mean values in each system was not so high in terms of US EPA criteria of fish health and human health, indicating that the impact was minor in the study site. Further studies should be done for the determination of mercury levels in the systems.