• Proceedings of the Korean Environmental Sciences Society Conference
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• 2008.11a
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• pp.173-176
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• 2008

출현한 식물은 총 61과 156종으로 조사되었는데 조사지점의 생육환경으로 볼 때, 출현 종수가 반드시 절토비탈면의 생성년수와 사면면적에 비례하여 출현하는 것만은 아니었다. 가장 출현빈도가 높은 분류군은 국화과로 14.7%이었고, 벼과 8.3%, 콩과 7.1%, 장미과 5.8% 순이었다. 각 조사지점별 우점종은 생성시기가 비교적 짧은 지점에서는 호밀풀, 바랭이 등의 사초과 식물들, 15년 이상의 표토층으로 된 지점에서는 사방오리나무, 아까시나무와 같은 목본류, 암반층으로 된 지점은 칡, 계요등, 송악 등의 덩굴성 식물들이었다. 귀화식물은 모두 13종이 출현하였고, 이에 의한 도시화지수는 4.8%로 환경변화가 비교적 적은 곳으로 조사되었다. Raunkiaer의 생활형으로 분류하면, 목본류 64종(47.5%), 지중식물 43종(27.6%), 1년생 식물 30종(19.2%), 반지중식물 7종(4.5%), 지표식물 2종(1.3%) 순으로 조사되어 식생의 천이가 안정화되어 가고 있음을 보여주었다.

• Korean Journal of Environment and Ecology
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• v.29 no.3
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• pp.333-343
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• 2015

This research aims at identifying the goshawk's possible and replaceable breeding ground by using the MaxEnt prediction model which has so far been insufficiently used in Korea, and providing evidence to expand possible protection areas for the goshawk's breeding for the future. The field research identified 10 goshawk's nests, and 23 appearance points confirmed during the 3rd round of environmental research were used for analysis. 4 geomorphic, 3 environmental, 7 distance, and 9 weather factors were used as model variables. The final environmental variables were selected through non-parametric verification between appearance and non-appearance coordinates identified by random sampling. The final predictive model (MaxEnt) was structured using 10 factors related to breeding ground and 7 factors related to appearance area selected by statistics verification. According to the results of the study, the factor that affected breeding point structure model the most was temperature seasonality, followed by distance from mixforest, density-class on the forest map and relief energy. The factor that affected appearance point structure model the most was temperature seasonality, followed by distance from rivers and ponds, distance from agricultural land and gradient. The nature of the goshawk's breeding environment and habit to breed inside forests were reflected in this modeling that targets breeding points. The northern central area which is about $189.5 km^2$(2.55 %) is expected to be suitable breeding ground. Large cities such as Cheongju and Chungju are located in the southern part of Chungcheongbuk-do whereas the northern part of Chungcheongbuk-do has evenly distributed forests and farmlands, which helps goshawks have a scope of influence and food source to breed. Appearance point modeling predicted an area of $3,071 km^2$(41.38 %) showing a wider ranging habitat than that of the breeding point modeling due to some limitations such as limited moving observation and non-consideration of seasonal changes. When targeting the breeding points, a specific predictive area can be deduced but it is difficult to check the points of nests and it is impossible to reflect the goshawk's behavioral area. On the other hand, when targeting appearance points, a wider ranging area can be covered but it is less accurate compared to predictive breeding point since simple movements and constant use status are not reflected. However, with these results, the goshawk's habitat can be predicted with reasonable accuracy. In particular, it is necessary to apply precise predictive breeding area data based on habitat modeling results when enforcing an environmental evaluation or establishing a development plan.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.10 no.4
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• pp.243-258
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• 1977

1 The coastal area between Youngdo and Jodo was a common coastal water not much different from other coastal waters before the construction of the breakwater between them. 2. The breakwater between the two islands shuts off the tidal currents and divides the area . into the two small isolated bays to create quite different environments. 3. To understand the differences between then, present study examined some environmental factors such as water temperature, salinity, dissolved oxygen, transparency, and major nutrients, phosphates, sillicates and nitrites and the phytoand zooplankton. The samplings were carried out monthly from March 1976 to February 1977 at 4 stations: 2 stations in each bay. 4. Some differences were observed in the environmental factors such as water temperature, salinity, dissolved oxygen and transparency between the two bays. 5. The distribution and occurence of nutrient salts of the two bays were distinctly different each other. Northern Bay had $138\%$ of nutrients in comparison with Southern Bay. 6. Phytoplankton in Northern Bay was about $200\%$ plentier than in Southern Bay. 7. Zooplankton in Southern Bay was about $180\%$ richer than in Northern Bay. 8. One of the pollution indicator species, Synedra ulna, was observed in Northern Bay and the occurence of Euglena sp. and ciliates were much higher in Northern Bay than in Southern Bay, but, in contrast, Sagitta sp. was more abundant in Southern Bay than in the other. 9. The areas of the two bays seem to be in its way to eutrophication especially in Northern Bay. 10. The two bays have been differentiated enough to identify each other.

• Korean Journal of Ichthyology
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• v.36 no.1
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• pp.48-57
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• 2024

Distribution status and extinction threat evaluation of an endangered species, Cobitis choii, were investigated from 2015 to 2019. In 2015 and 2018, we investigated past appearance sites of C. choii. In 2015, 163 individuals from nine sites were collected by surveying 19 stations. In 2018, 19 individuals from five sites were collected by surveying 22 sites. In 2019, 156 individuals from 12 sites were collected as a result of a survey of 79 sites of past appearance and potential appearance of C. choii. Appearance regions were Mihocheon (Baekgokcheon (2 sites), Chopyeongcheon (1 sites)), Gapcheon (3 sites), Yugucheon (2 sites), Jicheon (4 sites), and Geumgang mainstream (2 sites). Among these appearing regions, Baekgokcheon, Yugucheon, and Mihocheon mainstreams showed a sharp decline in population. Baekgokcheon was estimated to have a habitat change due to a project to raise the bank of Baekgok Reservoir. Yugucheon was estimated to have a habitat disturbance due to flood-induced collapse and reconstruction of weir. Mihocheon mainstream was estimated to have water pollution and habitat disturbance. On the other hand, Chopyeongcheon and Geumgang mainstream were newly habitat identified and Gapcheon was noted to show an increase in the number of individuals. After performing extinction threat evaluation, C. choii was evaluated as Endangered (EN A2ac) due to its rapid population decline (more than 50%) in its habitats of Baekgokcheon, Yugucheon, and Mihocheon based on criteria A, while it was evaluated as Vulnerable (VU B1ab (iii,v) +B2ab +B2ab (iii,v)) due to its narrow extent of occurrence (EOO, 1,735 km²) and area of occupancy (AOO, 36 km²) in 6 locations with a continuous population decline based on criteria B. Therefore, the final threat of extinction grade was evaluated as Endangered (EN A2ac). In Baekgokcheon, Yugucheon, and Mihocheon mainstream where the population has declined rapidly recently, conservation measures are urgently required to increase its population.

• Korean Journal of Environmental Biology
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• v.23 no.1
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• pp.71-88
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• 2005

This study has been monthly carried out to investigate the community structure and seasonal variations of Coleoptera from April to September, 2004 in Mt. Yeonyeop area, Gangwon-do, Korea. A total of 3053 individuals belonging to 358 species in 49 families have been collected in the studied area by light trap, pitfall trap and sweeping methods. The abundant families, based on the number of species, were Carabidae (50 species), Chrysomelidae (40 species) and Curculionidae (40 species). The number of species were highest at site 4, located in low altitude and contained stream. The number of individuals were highest at site 2, because many beetles were attracted by pitfall traps. The total number of species and individuals was highest in July. Nicrophorus (Nicrophorus) quadripunctatus (13.00%) was a dominant species and Synuchus (Synuchus) cycloderus (7.17%) was sub dominant species. Especially Damaster mirabilissimus mirabilissimus, a protected species by government, was collected in May.

• Proceedings of the Korea Water Resources Association Conference
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• 2009.05a
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• pp.1984-1988
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• 2009

본 연구에서는 하천 식생 및 어류 모니터링 결과를 바탕으로 청미천 유역의 본류에 대한 하천 수변환경을 평가하였다. 하천 식생은 홍수 전과 후로 구분하여 2회 조사하였다. 식생 조사는 Braun-Blanque의 조사 방법에 따라 표본구 내의 출현식물에 대해 조사하였고 표본구 면적은 자생지 주변의 특징과 형성된 군락의 최소면적에 근거하여 $2{\ast}2m^2$ 결정하였다. 1, 2차 조사 결과 공히 국화과 식물이 많이 출현하였고 다음으로 벼과 식물이 많이 출현하였다. 청미천 조사구간에서 볼 수 있는 식물은 21개과 38종이 출현하고 있는 것으로 조사되었다. 이중 국화과 7종과 벼과 5종, 콩과 4종으로 출현종이 많이 조사되었다. 화봉천 합류점에서는 총 123마리를 포획하여 동종 분류한 결과 1개과 3개아과 7개종이 출현하였다. 1지점의 경우 출현어종은 모두 잉어과로 피라미가 48%로 우점종을 차지하고 있었다. 죽산천 합류지점에서는 총 83마리를 포획하였으며, 출현어종은 1개과 2개아과 7개종의 어류이며 그중 붕어와 피라미가 각각 31%와 23%로 우점하고 있었다. 청미천 조사구간의 출현어종의 개체수를 보면 피라미 68.5%, 붕어 44.3%, 떡붕어 18.1%, 모래무지 14.3%, 왜매치 14.1% 순으로 나타나고 있으며 기타 출현어종은 대부분 4% 내외로 피라미가 우점종으로 조사되었다.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2004.05a
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• pp.249-251
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• 2004

감천항 3개 지점에서 조사된 식물플랑크톤은 3강 46속 98종류였는데 Bacillario-phyceae가 34속 76종류(77.6%), Dinophyceae 9속 17종류(17.3%, Chrysophycese 3속 5종류(5.1%)였다. 항 내에서 출현한 종은 모두 85종류로 항 외에서 출현한 94종류보다 적은 종이 출현하였고 규조류는 항 내에서, 와편모조류는 항 외에서 많이 출현하는 경향을 보였다. 계절별로는 가을에 62종류로 가장 많이 출현하였고 겨울에 45종류로 가장 적게 출현하였다. 지점별 현존량은 1,434(Feb. 2003; st. 3)~최고 17,708 cell/ml(Aug. 2003; st. 1)의 범위였고 여름철에 규조류(특히, Pseudonitzschia pungens와 Chaetoceros curvisetus 등)의 현존량이 많았다. 그리고 Pseudonitzschia pungens는 여름에 항 내에서 8,133 cell/ml로 가장 높은 현존량을 보였고 항 외에서도 4,000 cell/ml 이상 높은 현존량을 보였다, 본 조사기산 동안 출현한 주요종은 1,000 cell/ml 이상 출현한 우점종으로, Chaetoceros curvisetus, Chaetoceros debilis, Pseudonitzschia pungens, Skeletonema costatum, Stephanopyxis turris 등 5종, 출현빈번종은 Chaetoceros curvisetus, Chaetoceros lorenzianus, Skeletonema costatum, Thalassiosira hyalina 등 4종, 4계절 모두 출현한 종은 Chaetoceros didymus var. anhlica 외 13종이었으며 적조원인종도 Ceratium furca 외 13종으로 조사되어 항 내의 주기적인 조사가 필요할 것으로 판단되었다. 군집분석으로 우점도지수는 최저 0.205~최고 0.616였고 종다양성지수는 최저 0.213~최고 0.597로 나타났다.

• Korean Journal of Ecology and Environment
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• v.52 no.3
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• pp.274-283
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• 2019

Beta diversity is an efficient means of assessing the spatial variation in community composition among sites. To present fish community variation and LCBD (Local Contribution to Beta Diversity) among sites in stream, 6 sampling sites were selected in Cheonggye stream. Fish communities, environmental and habitat variables were collected at sites from April 2014 to October 2015. We used the total variance of the fish community data table (site-by-species community table) based on different forms, presence-absence, abundance, and Hellinger transformation, to estimate and compare beta diversity and LCBD. Fish community data table transformed by Hellinger distance showed the higher values of beta diversity than presence-absence and abundance data table. A similar patterns of LCBD were observed with presence-absence and Hellinger transformed data table. Low value of beta diversity calculated by community data table with abundance was due to the non-normality of fish assemblage data. Additionally, correlation coefficients were calculated to evaluate the relationships among LCBD, community indices and physicochemical variables. LCBD showed negative correlation coefficients with Shannon diversity. Overall, application of beta diversity analysis is an efficient method of addressing spatial variation of fish communities and ecological uniqueness of the sites in stream.

• Korean Journal of Ichthyology
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• v.25 no.4
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• pp.189-199
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• 2013

The distribution status and habitat characteristics of the endangered species, Lethenteron reissneri were investigated in 2011~2012 in Korea. During the study period, L. reissneri were collected 60 stations among 755 sampling stations investigated. The total numbers of ammocoetes and adults were 208 and 435, respectively from eight stations of the Han River drainage system, four stations of Geum River drainage system, 32 stations of Seomjin and Yeongsan River drainage systems, and 16 stations of Nakdong River drainage system. The Han and Geum river drainage systems, the Sapkyo Stream and independent streams running toward the East Sea were estimated to have suffered sudden reductions of population density, whereas the Seomjin River drainage system showed increased population density compared with historic occurrence records. L. reissneri inhabited the middle-upper stream of clean water with well-developed rapids and lots of aquatic organisms. According to IUCN Red List categories and criteria L. reissneri was assessed to be vulnerable (VU) [B2ab (ii,iii,iv,v);D1] because of the rapid reduction of the occupying areas and the small number of mature individuals. Besides the distribution status and habitat characteristics we discussed the conservation strategies of L. reissneri.

• Korean Journal of Environmental Agriculture
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• v.26 no.2
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• pp.159-170
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• 2007

This study was focused on the investigation of the phytoplankton flora and community structure for changing of water environment at the rivers in the lower part of Nakdong river, The samples for this study were collected every month from Jan. 2004 To Dec. 2004. the 196 species belonged to 94 genera were identified during this study periods. The number of species was recorded the maximum 124 taxa in summer and the minimum 69 taxa in winter, We observed the maximum taxa (92 taxa) at the site No. 20 and the minimum taxa (55 taxa) at the site No. 8, respectively. Among the phytoplankton communities, diatoms were dominated over 40% of total phytoplankton groups. Subdominant groups were green algae (over 20% of total phytplankton groups). During this study periods, the 60 species were investigated ecologically significant species (46 cosmopolitic species, 25 pollution indicator, 21 redtide causative species, 8 dominant species, and 7 frequently occurred species). According to the cluster analysis by similarity index, the study sites could be divided into 4 groups.