• 한국어류학회지
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• 제22권4호
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• pp.249-255
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• 2010

빙어(Hypomesus nipponensis)의 육봉형과 소하성 개체군의 특성을 연구하기 위해 2008년 12월부터 2009년 4월까지 소양호와 향호에서 조사하였다. 육봉형인 소양호 개체군과 소하성인 향호 개체군에 있어 두 집단 간에 형태적 차이는 유사하였다. 산란시기는 육봉형인 소양호에서는 3월이었고 소하성 향호에서는 2월말이었다. 성적으로 성숙하여 생식이 가능한 크기는 전장이 60mm 이상되는 개체로 육봉형과 소하성 개체군에 있어서 동일하였다. 생식소 지수는 육봉형 집단(암컷 20.5%, 수컷 3.7%)이 소하성 집단(암컷 17.4%, 수컷 3.3%)에 비해 다소 높았다. 포란수는 육봉형 개체군(평균 4,902개)이 소하성 개체군(평균 7,325개)에 비해 매우 적었고 육봉형 개체군이 소하성 개체군에 비해 전장도 매우 작았었다. 소양호 개체군의 비만도는 평균 0.60(0.49~0.74)이었고 향호의 비만도는 0.70 (0.47~0.76)이었다. 먹이생물은 동물플랑크톤과 수서곤충이었으며 향호에 서식하는 개체군이 소양호 개체군에 비해 먹이의 크기가 큰 것을 주로 섭식하고 있었다.

• Ecology and Resilient Infrastructure
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• 제5권2호
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• pp.94-104
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• 2018

The Soyangho Reservoir in Korea has a large drawdown zone, with an annual maximum water level fluctuation of 37 m due to dam operations to maintain a stable water supply and control flooding, especially during the monsoon period. The floristic composition, distribution and biomass of the major plant communities in the drawdown zone of the Soyangho Reservoir were assessed in order to understand their responses to the wide water level fluctuation. Species richness of vascular plants was low, and species composition was dominated by herbaceous annuals. Principal coordinates analysis using both flora and environmental data identified slope angle and the distance from the dam as important factors determining floristic composition. The species richness was low in the steep drawdown zone close to the dam, where much of the soil surface was almost devoid of vegetation. In shallower slopes, distant from the dam plant communities composed of mainly annuals were found. The large fluctuation in water level exposed soil where these annuals could establish. An overall biomass of 122 t (metric tons) Dry Matter was estimated for the reservoir, containing ca 3.6 t N (nitrogen) and ca 0.3 t P (phosphorus); the role of the vegetation of the drawdown zone in carbon sequestration and water pollution were briefly discussed.

• Journal of Plant Biology
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• 제16권3_4호
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• pp.17-34
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• 1973

The physico-chemical factors, the distribution of chlorophyll and the primary production of the lakes Hwajinpo, Yongrangho, Chunchonho, Uiamho, Soyangho and Changjamot have been studied in order to make ecological comparison among these lakes during summer stagnation period of August to September of 1973. On the basis of the characteristics of these lakes, the lake types have been discussed. Thermocline is observed at 3-4m zone in the lake Changjamot and 4-5m zone in the lake Yongrangho. In the case of lake Hwajinpo and impoundments, the distinct thermal stratification is not observed at the summer stagnation period. As to vertical distribution of dissolved oxygen, a positive heterograde curve is obtained in the lakes Hwajinpo and Yongrangho. In the lake Changjamot the typical clinograde curve and the oxygen depletion in hypolimnion are observed. In the case of impoundments, however, the orthograde curve is observed in the lakes Chunchonho and Uiamho. While in the lake Soyangho, any stratification of the disssolved oxygen is not found. In the brackish lakes, such as lakes Hwajinpo and Yongragho, the salinity of hypolimnion is found to be much higher than that of epilimnion. In the lake Hwajinpo, the salinity of hypolimnion is exhibited 32.7$\textperthousand$, which is nearly the same as sea water. The distribution of nitrogenous compounds and phosphates is found to be high in the lake Changjmot. The silicate is also found in high concentration in the lake Chunchonho, and the distribution of nutrients in the brackish lakes is generally low. As to the vertical distribution of chlorophyll level, the lake Changjamot shows a stratum type and the brackish lakes L-type stratification. In the impoundments, lakes Chunchonho and Uiamho appear to be homogeneous type. Seasonal variation of chlorophyll level in the lake Changjamot is examined from January to September 1973. The vertical distribution of chlorophyll during the period of circulation from January to April is homogeneous type and is stratum type thereafter. The maximum chlorophyll level is 277.4mg/$m^2$ on June 23 and the pattern of seasonal variation of chlorophyll level is comparable to the type of eutrophy. The horizontal distribution of chlorophyll level is studied in the brackish lakes, Hwajinpo and Yongrangho. The pattern of distribution is found to be an irregular type. On the basis of measurements of primary production by means of the carbon-14 method and the distribution of chlorophyll level, it is concluded that the interior part of the lake Hwajinpo and Changjamot are eutrophic and the exterior part of the lake Hwajinpo, lake Yongrangho and the impoundments, lake Uiambo and Soyangho are mesotrophic.

• 한국어류학회지
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• 제30권2호
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• pp.84-91
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• 2018

본 논문은 소양호에 서식하는 내수면어업의 주요 수산자원 중 하나인 쏘가리(Siniperca scherzeri)의 성숙과 산란에 관하여 연구하였다. 본 논문에 사용된 쏘가리는 2014년 4월부터 11월까지 정치망과 자망을 통해 채집하였고, 암컷이 204개체로 전장범위는 113~365 mm이었고, 수컷은 197개체로 전장 범위가 140~342 mm이었다. 산란기가 시작되는 5월의 수온은 $15^{\circ}C$를 나타냈으며, 점진적으로 높아져 7월에 $26^{\circ}C$를 나타내었다. 암컷의 생식소 숙도지수(GSI)는 5월에서 7월까지 각각 2.3%, 4.6%, 3.1%로 나타났고, 수컷의 경우 8.0%, 6.6%, 4.5%로 나타났다. 난소 조직은 5월에 많은 수의 샘플이 중숙으로 관찰되었으며 6월에는 대다수가 성숙, 7월에는 완숙 및 방란으로 관찰되었다. 정소 조직의 경우에도 마찬가지로 5월에는 대다수가 중숙, 6월에는 성숙, 7월에는 방중으로 관찰되었다. 월별 성숙도와 생식소 숙도지수 (GSI), 생식소의 조직관찰을 통한 분석결과, 소양호에 서식하는 쏘가리의 산란기는 5월에서 6월로 추정되었다. 또한 군성숙도를 분석한 결과, 암컷 쏘가리의 50% 성숙체장은 245.16 mm로 나타났다.

• 한국환경생태학회:학술대회논문집
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• 한국환경생태학회 2011년 학술대회 논문집 2호
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• pp.81-84
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• 2010

• Journal of Ecology and Environment
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• 제43권2호
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• pp.271-281
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• 2019

Background: The plant communities within reservoir drawdown zones are ecologically important as they provide a range of ecosystem services such as stabilizing the shoreline, improving water quality, enhancing biodiversity, and mitigating climate change. The aim of the study was therefore to identify the major environmental factors affecting these plant communities within the drawdown zone of the Soyangho Reservoir in South Korea, which experiences a monsoonal climate, and thereafter to (1) elucidate the plant species responses and (2) compare the soil seedbank composition along main environmental gradients. Results: Two main environmental gradients affecting the plant community structure were identified within the drawdown zone; these were a vertical and longitudinal gradient. On the vertical dimension, a hydrological gradient of flood/exposure, the annual-dominated plant community near the water edge changed to a perennial-dominated community at the highest elevation. On the longitudinal dimension from the dam to the upstream, plant species composition changed from an upland forest-edge community to a lowland riverine community, and this was correlated with slope degree, soil particle size, and soil moisture content. Simultaneously, the composition of the soil seedbank was separated along the vertical gradient of the drawdown zone, with mainly annuals near the water edge and some perennials at higher elevations. The species composition similarity between the seedbank and extant vegetation was greater in the annual communities at low elevation than in the perennial communities at higher elevation. Conclusions: The structures of plant community and soil seedbank in the drawdown zone of a monsoonal riverine reservoir were changed first along the vertical and secondly along the longitudinal gradients. The soil seedbank could play an important role on the vegetation regeneration after the disturbances of flood/exposure in the drawdown zone. These results indicate that it is important to understand the vertical and longitudinal environmental gradients affecting shoreline plant community structure and the role of soil seedbanks on the rapid vegetation regeneration for conserving and restoring the drawdown zone of a monsoonal reservoir.

• 한국산학기술학회논문지
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• 제15권8호
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• pp.5363-5368
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• 2014

본 논문은 소양호 유역을 대상으로 배수구역의 유달오염부하량을 산정하여 유황 및 계절변화에 따른 소양호 유역에 미치는 기여율을 평가 하였다. 유황변화에 따른 배수구역의 기여율을 보면 인북천 유역의 SS와 T-P 항목이 평수량 이상과 저수량 기간에서 46%와 51%의 기여율을 T-P는 평수량 49.5%, 저수량 기간은 48.5%의 기여율을 보였다. 다음으로 계절 변화에 따른 기여율을 관찰한 결과, 인북천 SS 항목이 전 계절 동안 39.6%에서 44.3%를 T-P는 53.8%로 다른 배수구역에 비하여 높은 기여율을 보였다. T-N은 전 계절에서 내린천 유역이 39.6%에서 44.3%의 기여율을 보였다. 전체적으로 인북천 유역의 SS와 T-P 항목, 내린천의 T-N이 소양호 유역의 오염물질 유출에 높은 기여율을 보였다.

• Parasites, Hosts and Diseases
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• 제38권1호
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• pp.37-39
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• 2000

Many Koreans usually eat raw pond smelts, Hypomesus olidus, in the winter. This study was performed to evaluate the infection status with trematode metacercariae in pond smelts from January 1998 through February 1999. Among 1,305 fish collected, 459 were purchased from wholesale dealers in Chinchon-gun, Chungchongbuk-do, and the rest of them were caught with a casting net in Soyangho (Lake), Taehoman (Bay) and Paekkokchosuchi(Pond). Seven species of trematode metacercariae including two unidentified ones were detected from 1,305 pond smelts. The number of detected trematode metacercariae according to the species are as follow: Clonorchis sinensis 8, Holostephanus nipponicus 7, Cyathocotvle orientalis 24, DipLostomum sp. 14, and Metorchis orientalis 7. From the above results, it was confirmed that H. olidus plays a role as the second intermediate host of some kinds of trematode including C. sinensis in Korea. Our report shows possible clonorchiasis caused by eating raw pond smelts.

• 한국방재학회 논문집
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• 제8권3호
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• pp.123-128
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• 2008

본 연구는 소양호 상류유역의 자운천 유역을 대상으로 2005년 1개년동안 유량과 탁도를 조사하여, 월별로 강우특성에 따른 하천의 탁도가 변화하는 양상을 고찰하였다. 고찰결과, 5월$\sim$8월에 강우강도 및 강우지속시간에 의하여 높은 탁도가 발생되는 것을 알 수 있었으며, 반면 9월 이후에는 강우의 초기 세척효과로 인하여 탁도가 낮게 지속적으로 발생되는 것을 확인하였다. 다음으로 탁도에 대한 지배인자의 영향력을 살펴보았으며, 5월, 6월에는 지배인자중 강우강도가 89%, 7월, 8월에는 강우강도가 67%, 강우지속시간이 32%로 탁도 발생에 유의적인 영향을 미치고 있는 것을 확인하였다. 또한 탁도 발생에 영향력 있는 지배인자에 대하여 회귀분석을 실시하여 회귀식을 제안하였다.

• 농촌계획
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• 제23권2호
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• pp.55-65
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• 2017

This study is to estimate the circuity factors which can be used to assess for public facilities accessibility and analyze traffic in the area. We set the range of the administrative districts by Si Gun Gu unit and Eup Myeon Dong unit (more subdivided unit than Si Gun Gu unit). The average circuity factor in Si Gun Gu unit is 1.364 (maximum 2.953 and minimum 1.711). The region indicated the highest value of circuity factor is wando-gun in jeollanam-do, which area consists of 4 island and is connected to the bridges. Having to use the bridges for using public facilities hinders its accessibility. In the case of Eup Myeon Dong unit, the average circuity factor is 1.353 (maximum 2.950 and minimum 1.154). The region indicated the highest value of circuity factor is buksan-myeon in chuncheon-si, Gangwon-do. This region also has to use bridges for using public facilities because there is the largest lake, called Soyangho. This circuity factor is used to analyze the location of public facilities and assess vulnerability of accessibility. And also the factor can be applied to some policies, such as rural public service planning based on spatial big data.