• Korean Journal of Ecology and Environment
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• v.43 no.2
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• pp.190-198
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• 2010

This study was conducted to examine the effects of dams on benthic macroinvertebrate communities in Korean streams and rivers. Four low-head dams and three large dams were studied throughout South Korea. Sampling was taken at immediately upper (impoundment), lower (riffle area), and control (riffle area) sites from the dams during 2004-2007. The upper sites, of which substrate heterogeneity and velocity were relatively low, showed a lower degree of species richness, density, and diversity indices, which is very different from the lower and control sites. Heavily polluted streams showed a lesser degree of community differences between the upper and lower sites. In the large dams, the upper and lower sites showed very low values of species diversity indices and very high values of dominance indices compared to the control sites. In the low-head dams, however, the difference of degree of the values was relatively smaller. Compositions of the functional feeding groups and the habitat orientation groups were relatively simpler at the upper sites than at the lower sites and the degree of difference was greater in the large dams. Species richness and community indices of benthic macroinvertebrates were more significantly affected by habitat characteristics than water quality at the upper sites; however, those were more significantly related with water quality at the lower sites. In conclusion, large and low-head dams could simplify stream habitats particularly at the upper sites (impoundment), and they negatively affected on the benthic macroinvertebrate communities inhabited the habitats. The impact was larger in the large dams than in the low-head dams.

• Journal of the Speleological Society of Korea
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• v.38 no.39
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• pp.34-57
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• 1994

우리나라의 주민생활을 이해하는데는 먼저 지형지모에 대한 이해로부터 시작되어야한다. 지형지모의 근간이 되는 산세가 가장기본 토대가 되고 이에 따른 하천수계의 상태가 주민생활과 밀접하게 관계되고 있다. 본 연구는 우리나라 북부지방의 하천수계가 어떻게 흘러가고 있으며, 이들 강과 하천이 어떤 상태이며, 그리고 우리주민생활무대인 평야로 발달시키고 있는가를 분석 한 것이다. 실제로 하천은 침식과 운반 그리고 퇴적 등의 세가지 유수작용을 하고 있으므로 지구표면 각지역에 넓은 생활터전인 평야지역을 발달시켜 주고있다. 이로 말미암아 인류문화의 발전근거가 바로 하천과 평야에 근거되고 있다고 볼 수 있는 것이다.(중략)

• Korean Journal of Ichthyology
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• v.17 no.1
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• pp.1-7
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• 2005

A new chub, Zacco koreanus sp. nov., is described on the basis of 104 specimens from six localities in Korea. The new species is distinguished from other Zacco species by the following characteristics: 9~10 scales above lateral line to dorsal fin origin, yellowish anterolateral side of body, no hemicircular red blotch on the upper margin of the eyes, reddish anterior margin of pectoral fin, larger orbit diameter and narrow interorbital width. The new species is widely distributed in the most streams of Korea, except the Yeongsan R., while Zacco temminckii is restricted in the Dongjin R., Yeongsan R., Seomjin R., Tamjin R. and Nakdong R. in Korea. When the two species occurred sympatrically in the same stream, Z. koreanus sp. nov. prefered mostly rapid lotic environments while Z. temminckii inhabited lentic ones. The Korean Z. temminckii was redescribed herein. A key to the Zacco species of Korea and Japan is provided.

• Korean Journal of Organic Agriculture
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• v.17 no.2
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• pp.193-209
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• 2009

Total collected benthic macro invertebrates in rice paddy fields were identified 3 phylum, 5 class, 13 order, 25 family, 32 genera and 36 species, those in organic rice field were 12 order, 22 family and 28 species, and in conventional rice field were 10 order, 19 family and 25 species. The almost collected species inhabit lentic zone but Semisulcospira libertina, Corbicula fluminea, and Tipula sp. were habitat on lotic zone. The number of benthic macro invertebrates species was higher in organic paddy field than in conventional field. Eleven species were collected only on organic but eight species only on conventional field. The number of individuals were 870 on organic rice field which higher 3.6-fold on conventional field. The diversity indices of organic rice field were 1.57-2.45 and 0.71-2.61 in the first and second survey, respectively. The higher diversity indices, the lower dominance indices.

• Proceedings of the Korea Water Resources Association Conference
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• 2008.05a
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• pp.1536-1539
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• 2008

본 연구는 하천을 가로막고 있는 기능을 상실한 횡단구조물 철거를 통하여 하천 생물들이 자유로이 이동할 수 있는 생태통로를 복원하기 위한 연구이다. 이를 위하여 기능을 상실한 보인 경기도 연천군 전곡읍 한탄강 소재의 길이 190m, 높이 2.8m 규모의 고탄보를 철거하여 철거에 의한 보 상하류에서 하상변동과 하천형태 변화와 같은 물리적 영향, 수질 변화와 같은 화학적 영향, 보 상하류에서의 어류/저서동물/식생의 생태 서식처 변화와 같은 생물적 영향을 분석하였다. 그 결과, 어류의 경우, 철거 이전에 보 최상류역 대조구간에서 조사된 16종이 26종으로 늘어났으며, 특히, 뱀장어, 강준치, 쏘가리와 같은 어류의 개체수가 증가되었다. 보 철거를 통하여 이동통로가 확보됨으로써 종다양도 지수가 전반적으로 상회하는 경향을 나타내었다. 저서무척추동물의 경우, 보 철거로 인하여 정수역었던 곳이 유수역으로 변모함에 따라 철거 전에 출현했던 잠자리와 다슬기 종류는 발견되지 않았던 반면, 철거 전에 출현되지 않았던 날도래류가 출현하는 등 출현 종에 다소의 변화를 보였다.

• Proceedings of the Korea Water Resources Association Conference
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• 2004.05b
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• pp.932-936
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• 2004

수제는 하천에서의 흐름 방향과 유속을 제어하여 하안 또는 제방을 유수에 의한 침식작용으로부터 보호하기 위해 호안 또는 하안 전면부에 설치하는 구조물이다. 수제를 설치하는 목적은 하안 및 제방의 보호, 유로의 제어, 그리고 수환경의 개선 등을 들 수 있다. 국내에는 해방 이후 수제의 시공 사례가 거의 없었으나, 최근 들어 자연형 하천파 하천생태계 복원에 대한 관심이 점증하면서 수제에 대한 관심이 커지고 있다. 그러나 현재 국내에는 수제설계에 대한 실증적인 지침이 미비하고 국외의 기준을 검증 없이 소개하는 수준이어서 현장의 설계단계에서 수제공의 채택을 망설이게 하는 원인이 되고 있다. 이 연구에서는 국내${\cdot}$외 수제의 현황과 기술 동향을 파악하여 수제의 기하학적 특성인 수제길이, 수제길이, 그리고 설치각도의 3가지 설계인자를 조합하여 실험을 실시하였다. LSPIV 기법을 적용하여 측정한 유속자료를 분석한 결과 수제역 내 평균유속이 유입부 유속에 비해 $40\%$ 이하로 감소하는 것을 관찰할 수 있었다. 유속성분을 통하여 수제역 내 와도 및 사분면 검토를 실시한 결과 수제역 내에서는 비교적 안정적인 수치를 보이고 있어 호안침식방지에 유리한 것으로 보인다. 수제의 길이가 하폭의 $15\%$ 이하인 경우 상향 또는 하향수제가, $20\%$ 이상인 경우 직각수제가 유리한 것으로 나타났다.

• Ecology and Resilient Infrastructure
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• v.11 no.3
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• pp.78-89
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• 2024

Estuarine provides unique environmental conditions in terms of salinity concentration and sediment change patterns as freshwater and seawater mix. These conditions allow it to possess biodiversity that cannot be found in other ecosystems. This study was conducted to investigate and analyze distribution characteristics and biota of vegetation in the Gonyangcheon Estuarine Wetland, a brackish area, to prepare basic data for the conservation and sustainable use of estuarine wetlands. The vegetation in the Gonyangcheon Estuarine Wetland was classified into 23 plant communities across a total of six physiognomic vegetation types, including lentic herbaceous vegetation, lotic herbaceous vegetation, salt marsh vegetation, segetal vegetation, and substitutional vegetation. In particular, the Zoysia sinica community was widely distributed in the lower reaches, showing typical characteristics of tidal wetland and increasing its conservation value. From a biodiversity perspective, a total of 1,067 species were identified (an increase of 53 species compared to 2012) and 15 species of endangered wildlife were identified. Gonyangcheon Estuarine Wetland is an open estuary with excellent ecological connectivity. Various topography and landscapes such as rice paddies, forests, and salt marshes were organically developed and distributed, playing a positive role in promoting biodiversity, including brackish water organisms. Therefore, systematic conservation of the Gonyangcheon Estuarine Wetland will contribute to protecting migration routes of organisms and promoting ecological stability by securing a wetland ecological axis connected to the coast.

• Journal of the Korean Chemical Society
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• v.47 no.4
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• pp.309-314
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• 2003

In order to find out the microscopic environmental information on the nonionic reverse micelle of Triton X-100/n-hexanol/water in cyclohexane, an absorption and fluorescence spectroscopic study has been conducted using a methylene blue(MB). The information on the microscopic states of water in the polar core of the reverse micelle has been found by investigating complex formation and solvatochromic behavior between MB and Triton X-100. As a result, it was found that there exist three states in the polar core of the reverse micelle. The measured values of $W(=[H_2O]/[Surf])$ for the three states of water are 0.71, 4.98, and 7.26, and the corresponding lifetimes of MB are $15.45 ns{\pm}0.56$, $12.27 ns{\pm}0.79$, and $8.28 ns{\pm}0.82$, respectively.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.608-612
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• 2006

산지사면에서의 토양침식량은 실제 유역을 빠져나가는 토사유출량과 같지 않다. 이는 토사가 이동하는 과정에서 지형적인 요인 등에 의해 퇴적되거나, 가중되는 유수에 의해 더 많은 토양이 침식될 수 있기 때문이다. 토사유출률(SDR)은 유역의 크기뿐만 아니라 지형, 기후, 토양, 식생피복, 토지이용도 등에 관계된다. 본 연구에서는 기후 특성인 강우크기에 따른 토사유출률의 변화를 분석하고자 하였다. 산불 이후 5년 동안 산지 소유역의 시험유역을 운영하여 유출 및 토사유출량을 실측하여 자료를 구축하였고, 이 유역에 산지지역의 토양침식 모형인 SEMMA을 적용하여 토양침식량을 산정하고 유역출구로 이송한 실제 토사유출량과 비교하였다. 5년 동안 SDR은 전반적으로 감소하고, 강우량, 강우강도, 강우에너지와 같은 강우사상의 크기에 따라 증가한다. SDR은 2001년에서 2002년까지 대부분 1.0 이상이고, 2005년에는 1.0을 초과하지 않으며, 강우특성 뿐만 아니라 식생피복, 산불시간경과 등의 인자에 의존한다.

• Animal Systematics, Evolution and Diversity
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• v.11 no.1
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• pp.39-64
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• 1995

A faunistic and ecological study on the occurrence of freshwater cladocerans and copepods was accomplished from Chindo, South Korea. Collections were made from total 35 stations, comprising the various freshwater habitats like reservoirs, streams, swamps, bogs, ricefields, ditch, pond, and spring during the periods of July 23-25, and November 1-3 in 1994. Twenty seven cladoceran species of 17 genera of 6 families in 2 orders, and 28 copepod species of 21 genera of 6 families in 3 orders were collected during this research period, of which Daphnia obtusa Kurz and Elaphoidella bidens (Schmeil) are newly recorded from Korea. In reservoirs, Diaphanosoma sp. and Thermocyclops taihokuensis were dominant in July, and then succeeded by Bosmina longirostris and Cyclops vicinus vicinus in November. Thermocyclops crassus co-occurred with 7: taihokuensis at both seasons, was frequent in November after T. taihokuensis precipitately decreased. In other stagnant waters, 7: taihokuensis and Moina weismanni were dominant at ponds in July and in November, respectively. At ricefields in July Moina macrocopa and T. taihokuensis were dominant, but in November M. macrocopa and Paracyclops fimbriatus were. At streams, cladocerans were relatively rare, but became more rich in November. The representative cladoceran species were Bosmina longirostris as a plankton, and Chydorus sphaericus as a epibenthic species. Concerning copepods, nearly all the stations of streams except a few ones adjacent to seashore showed the similiar species constitutions, of which E. serrulatus and M, pehpeiensis were most frequent and abundant. At a mountain streamlet and a spring, the occurrence of Alona sp., Attheyella byblis Chang and Kim, 1992 and A. tetraspinosa Chang, 1993 is quite interesting and deserved much attention in the taxonomical point of view. Seventeen major cladocerans and copepods from lentic habitats and 13 major cladocerans and copepods from lotic habitatats were clustered using average taxonomic distance and UPGMA to infer the co-occurrence relations among species. As for lentic habitats, two large phena were appeared at first. The one phenon consisted of Diaphanosoma sp. and T taihokuensis, and showed its predominancy over the various habitats and its dominancy was rapidly decreased in November. The other phenon frequently occurred rather in November, and subdivided into three subgroups. On the other hand, as for lotic habitats, 13 species were also grouped into 2 large phena. The first one comprised 4 species, which were dominant and highly frequent at nearly all the lotic habitats, and subdivided into three subgroups according to their seasonal fluctuation types. The second one was also subdivided into three phena, the first of which comprised only one species, Microcyclops varicans, and occurred at most of the stations along stream with steadiness through the research period; the second phenon, Chydorus sphaericus, occurred much frequently in November; the last phenon included a few heterogenous subgroups.