• Ocean Science Journal
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• 제42권2호
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• pp.81-88
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• 2007

The paper reviews data available on euglenophycean algae of the genus Eutreptiella from the Russian waters of East/Japan Sea. Five species (such as E. braarudii, E. eupharyngea, E. gymnastica, E. cf. marina, and E. pascheri) were identified in our study. E. cf. marina and E. pascheri were found for the first time in the fare astern seas of Russia (including East/Japan Sea, Bering and Okhotsk seas). Morphological descriptions of species are based on light and electron microscopical studies and supplied with information on ecology and distribution. Original micrographs of these species obtained by light and electron microscopy are presented. It was established that E. eupharyngea, E. gymnastica, and E. pascheri cause water "blooms" in spring and summer in eutrophic coastal areas of Peter the Great Bay (East/Japan Sea), where their cell concentrations at these periods exceed $1\times10^6\;cells\;l^{-1}$.

• 한국물환경학회지
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• 제23권1호
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• pp.81-86
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• 2007

This paper describes a study on the role of limestone which might affect the dissolution of phosphates when phosphate containing sediments are put under anaerobic conditions. A small quantity of calcium hydroxy-apatite, alone or mixed with limestone powder, was put in contact with aqueous solution of acetic acid or carbonic acid, and variations of phosphate concentration were determined time dependantly. The results showed that the concentration was remarkably low in the presence of limestone, signifying that the coexistence of limestone suppresses the dissolution of phosphate by organic acid and/or carbonic acid. Separate experiments conducted by developing an anaerobic condition, after mixing lake sediments with dried leaves and limestone, showed that the existence of limestone suppressed the dissolution of phosphate. These results show that the application of limestone might be a useful measure to prevent deterioration of water quality originated from eutrophication by inhibiting the internal loading of P in eutrophic water-bodies.

• Water Engineering Research
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• 제1권3호
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• pp.199-208
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• 2000

The relationship between areal total phosphorus(TP) and areal hydraulic loading was identified and used as defining the trophic state of the reservoir. And three simple, conceptual TP models were tested against the measured in-reservoir TP concentration. The analyses were based on water quality data measured in the Ki Heung reservoir for two years. The results showed that Ki Heung reservoir has undergone eutrophic state, and Dillon's and Vollenweider's TP models were in close agreement with the measured annual mean TP concentration. However, the OECD's model understimated the measured annual mean TP concentration in the Ki Heung reservor. A discussion is given for the hypothetical application of TP loading plot which might be useful for establishing the TP control program in the resavoirs/lakes.

• 해양환경안전학회지
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• 제3권S1호
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• pp.77-90
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• 1997

the observations in situ and the seawater analyses were conducted in July and August, 1996 for the purpose of evaluating the characteristics of seawater quality centered on eutrophication in Mokpo harbour. By applying the OECD standards of trophic classification to the parameters such as secchi depth, total inorganic nitrogen, phosphate phosphorus and chlorophyll-a, the trophic level of seawater in Mokpo harbour was evaluated to be in eutrophic state in summer. By the estimation of pollution index with relation to eutrophication, the seawater quality of Mokpo harbour was evaluated to be under the regular grades and this evaluation was found to be different from the results of evaluation obtained by the environmental index of single parameter, chemical oxygen demand. By the estimation of eutrophication index, the seawaters of Mokpo harbour were shown to have the high potentiality of red tide occurrence.

• Journal of Plant Biology
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• 제14권1호
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• pp.15-23
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• 1971

The productivity of summer phytoplankton communities in Lake Hwajinpo, Lake Yongrang and Lake Changja were studied by measuring vertical variation of chlorophyll a amounts. The author also classified the lake types on the basis of the amount of chlorophyll in the lake water. And in Lake Changja, the seasonal changes of stratification of chlorophyll were studies. In Lake Hwajinpo, the productive structure of the phytoplankton community in summer was found to be L-shaped and of the mesotrophic type. In Lake Yongrang, the productive structure of the phytoplankton community in summer was alo L-shaped and of the mesotrophic type. And maximum chlorophyll layer was near the lake bottom below the compensation depth. In Lake Changja, the structure of phytoplankton community in summer was reversed L-shaped and of the eutrophic type, with the maximum chlorophyll layer just below the surface. The vertical distribution of chlorophyll amounts as a measure of the productive structure almost always formed a stratum distribution except in September and sometimes in May, in Lake Changja. In September homogeneous distribution was observed.

• 한국물환경학회지
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• 제30권4호
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• pp.429-440
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• 2014

This study was conducted to investigate the main cause of water quality deterioration during the spring season in the transition zone between the South Han River and the river-reservoir Paldang. A water quality model modified from QUAL2E (U.S.EPA) was used, and the model showed that eutrophication and algal production in the low flow season affected about 60% of the organic pollution at the downstream of the South Han River. This result means that phosphorus control is prior to external organic material management to ameliorate the deterioration of water quality in the water body.

• The Korean Journal of Ecology
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• 제12권4호
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• pp.237-244
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• 1989

The moor vegetation of Daeryong-po on Mt. Daeam, east-central Korea was investigated in July 26th-29th, 1989, It was classified into I community group, 4 communities and 5 subcommunities; Sanguisorba tenuifolia var. alba community group, Sphagnum palustre community. Typical subcommunity, Eleocharis mamillata var. cyclocarpa subcommunity, Carex canescense subcommunity, Carex dispalata community, Spiraea salicifolia community, Geranium eriiostemon var. megalanthum community, Arundinella hirta-Phragmites communis subcommunity, Angelica purpuraefolia subcommunity. According to this classification, the actual vegetation map was made. The distribution of vegetation in this moor was divided characteristically into two areas. One was a typical oligotrophic area characterized by S. palustre community. The other was an area having mesotrophic or eutrophic conditions where its original state was disturbed by inflow of soil particles and removal of peat. It this disturbed area, C. dispalata, S. sibiricus, G. eriostemon var. megalanthum, were invaded.

• 한국미생물·생명공학회지
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• 제25권3호
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• pp.322-327
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• 1997

Photosynthetic bacterium strain N-1 was isolated from the eutrophic wet soil and identified as Rhodospirillum rubrum. The optimum conditions for the cultivation of R. rubrum N-1 were estimated as 0.2% (w/v) of sodium acetate, 0.2% (w/v) of sodium propionate, 0.2% (w/v) of sodium butyrate in the Lasscelles basal medium at 30$circ$C, pH 7.0 under 4000 lux of the illumination. The removal efficiencies of total organic acid and chemical oxygen demand (COD$_{Cr}$) in swine wastewater were 80% and 87%, respectively, when 10% (v/v) of R. rubrum N-1 was inoculated.

• 생태와환경
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• 제37권1호통권106호
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• pp.36-46
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• 2004

소규모 부영양 저수지에서 식물플랑크톤 성장에 대한 제한영양염과 N/P무게비의 영향을 평가하기 위해 2002년 11월부터 2003년 12월까지 이루어졌다. 조사기간 동안 수체 내 DIN/DTP과 TN/TP 무게비는 각각 17${\sim}$187,33${\sim}$60의 범위로 나타났다. 용존무기질소의 대부분은 질산성 질소($NO_3$-N)형태로 존재했으며, 봄에 일시적인 암모니아 농도의 증가가 나타났다. 반면에 무기인은 8.8${\sim}$0.6 ${\mu}g\;P\;L^{-1}$의 범위로 계절에 따른 변화는 적었으며, 용존총인은 26.5 ${\sim}$ 10.1 ${\mu}g\;P\;L^{-1}$로 8월에 가장 높았고 12월에 가장 낮은 농도를 나타냈다. 엽록소 a 농도는 28.8${\sim}$109.7 ${\mu}g\;L^{-1}$의 범위였고, 식물플랑크톤 세포밀도 변화와 유사한 계절적인 변화를 보였다. 봄에는 주로 규조류(Melosira varians)와 녹조류 (Dictyosphaerium puchellum)가 우점종으로 나타난 반면 5월부터 결빙 전까지는 Osillatoria SPP., Microcystis SPP., Aphanizomenon SP. 와 같은 남조류가 우점하였다. 남조류 군집 중 Microcystis SPP.가 우점한 6월부터 12월까지 수체 내 TN/TP비는 46${\sim}$13의 범위 (평균 27${\pm}$5)였다. 영양염 첨가실험의모든 경우(17번)에서 인에 의한 제한이 나타났으며, 질소제한은 8번에 걸쳐 나타났다. 식물플랑크톤 성장률은DIN/DTP비 30이하에서 가장 크게 나타났고, 인 농도50 ${\mu}g\;P\;L^{-1}$까지는 지속적으로 증가하였다. 절대 농도에 있어서 차이가 있으나, N/P비가 동일한 상태에서의 남조류 성장은 질소 농도가 3.5 mg N $L^{-1}$인 경우 N/P 비가 1인 상태에서 성장량이 가장 컸다. 인 첨가에 따른 성장은 질소농도가 높을수록 현저히 높게 나타났다. 이러한 결과들은 수체 내 질소농도가 높은 환경에서는 식물플랑크톤성장에 대한 강한 인 제한이 나타나기 쉬운 반면, 질소제한 가능성 이 상대적으로 적음을 의미한다.

• 환경생물
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• 제29권3호
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• pp.162-170
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• 2011

본 연구는 해역의 수질오염 특성을 알아보기 위해서 2010년 2, 5, 8, 11월에 광양만 20개 정점과 진해만 23개 정점에서 COD (화학적산소요구량, Chemical Oxygen Demand), Chlorophyll a, 대장균 Escherichia coli를 조사하였다. 또한, 광양만과 진해만의 지형학적특성을 고려하여 각각 3개 구역, 4개 구역으로 나누어 평가하였다. 광양만의 COD농도는 춘계 (평균: 4.3 mg $L^{-1)$)에 가장 높았고, 구역 I (반폐쇄성 해역; 정점 1~9)에서 평균 5.64 mg $L^{-1)$으로 가장 높았다. Chl. a농도는 하계 (평균: 14.0 ${\mu}g\;L^{-1)$)에 현저히 높았고, 구역 I에서 최고치 25 ${\mu}g\;L^{-1)$를 보였다. E. coli군수는 하계에 높게 나타났고, 섬진강에 가장 가까운 정점 10에서 최고치 2,094 cfu $L^{-1)$를 기록하였다. 반면, 외측정점 (정점 15~20)으로 향할수록 그들의 개체수는 현저하게 줄어드는 양상을 보였다. Chl. a는 섬진강의 영향을 받는 광양만의 산업단지와 대도시가 인접하고, 수계의 혼합이 적은 지역에서 가장 높았다. 진해만에서는 구역 I (마산만과 행암만의 부영양화된 수역)에서 다른 구역에 비해 집중되어 E. coli군수를 보였다. 구역 I에 속하는 정점 중 육상에 가장 가까운 정점 1, 4, 5에서 다른 정점에 비해 많은 E. coli군수를 나타내었으며, 특히 동계에 정점 4에서 최고치 (5,250 cfu $L^{-1)$)를 보였다. 그 외 춘계와 동계에 구역 IV에서 각각 평균 336 cfu $L^{-1)$, 383 cfu $L^{-1)$로 비교적 많은 E. coli군수가 관찰되었다. 광양만의 COD와 Chl. a와의 상관성이 관찰되지 않았으나, 진해만에서는 유의한 상관관계를 보였다 (r=0.49, p<0.001). 결론적으로, 본 연구에서 얻은 결과는 해역의 지형학적특성에 따른 수질오염을 가늠할 수 있는 기초적인 자료로 활용가능하다고 판단된다.