소양호의 DOC와 POC의 분포

김범철,최광순,김철구,이유희,김동섭,박제철 江原大學校 附設 環境硏究所 1998 環境硏究 Vol.15 No.-

Seasonal and vertical distributions of dissolved and particulate organic carbon were investigated from May 1995 to March 1997 in n deep mesotrophic reservoir, Lake Soyang, POC contentrations at the dam site ranged from 0.1 to 1.8 mgC/L and DOC concentrations ranged from 1.4 to 4.9 mgC/L. POC concentrations in the surface layer were higher in the season of cyanobacterial bloom, July to September. High POC was observed at the depth of 30 to 60m after storm runoff in summer monsoon season. Turbid storm runoff formed intermediate current laden with much particulate materials from terrestrial sources. The vertical and seasonal variation of DOC was smaller than POC. Higher DOC was observed near the lake bottom which implies sedimentation and degradation of much organic detritus at the bottom. The ratio of DOC : POC varied from 2 to 60, and the ratio was lowest in September 1995 when algal density was highest. DOC : POC ratio of the main inflowing river, the Soyang River, varied from 1 to 10, and the ratio was low in storm runoff when the POC concentration was high.

Suwa호 방류수내 남조류 독소(microcystin)의 일변화

김호섭,김범철,박호동,片上幸美,황순진 江原大學校 附設 環境硏究所 2001 環境硏究 Vol.18 No.-

The temporal and diel changes of cyanobacterial cell density, species composition, and cyanobacterial toxins (microcystin-RR, -YR, -LR) were examined for the outflow water of Lake Suwa in Japan from May to October, 1998. The highest total cell densities of Microcystis were observed in July and September, when the dominant phytoplankton was Microcystis ichthyoblabe and M. viridis, respectively. Both the species composition and total cell density of Microcystis affected the variation of the concentration of three microcystin variants. Only microcystin-RR(MC-RR) and -LR(MC-LR) were detected in July when Microcystis ichthyoblabe dominated, while microcystin-RR, -YR(MC-YR) and -LR were detected in August and October when Microcystis viridis dominated. The microcystin concentration and the cell density of Microcystis in the outflow water showed diel variations; the ratio of maximum to minimum value was 3~20 fold for microcystin concentration, and 5~31 fold for cell density. The diel variations of toxin concentration as well as Microcystis cell density was closely related to the diel variation of wind. During the windy period, when higher speeds occurred in the afternoon hours than morning hours, both the cell density of Microcystis and microcystin concentration tended to increase in the morning and decrease in the afternoon. The results of this study suggest that controlling the timing of lake discharge at the floodgate or intake tower can be useful for water resource management with respect to decreasing cyanobacteria biomass within intake water.

박스-젠킨스법을 이용한 소양호 수질변화 시계열분석

김범철,윤용운,정태영,박석순 이화여자대학교 환경문제연구소 1997 이화환경연구 Vol.1 No.-

Statistical models were developed using the Box-Jenkins time series analysis to simulate changes of water qualities in Soyang Lake. The water qualities included in the models are total phosphorus(TP) and chlorophyll-a(CA). The model development was based on the data obtained from Feb. 1987 to Oct. 1992 for TP and from Mar. 1985 to Oct. 1992 for CA, and followed the typical procedures of the Box-Jenkins method including identification, estimation, and diagnostic check. From the computed autocorrelation function (ACF) and partial autocorrelation function(PACF), it was determined that the TP model should have two autoregression (AR) parameters and one moving average(MA) parameter, and two seasonal AR parameters and one seasonal MA parameter. The CA model was determined to have two AR parameters and two MA parameters, and two seasonal AR parameters and on seasonal MA parameter. Both models had seasonality of twelve months and were formulates as SARIMA(2,1,1)×(2,1,1)₁₂for TP and SARIMA(2,0,2)×(2,1,1)₁₂ for CA. The models were validated by testing normality and independency of the residuals. The model prediction ability was tested using the data collected from Nov. 1992 to July 1994 both for TP and CA. There were good agreements between the model predictions and the field measurements. Most of the predicted values were located within the 95% confidence limits except certain period of chlorophyll-a. It was concluded from this study that the Box-Jenkins time series analysis would be an effective tool to understand and simulate the long term variations of water qualities in Soyand Lake.

Primary Productivity Measurement by Photosynthesis-Irradiance Model Method in Lake Soyang and the Behavior of Model Parameters

김범철,김동섭 江原大學校 附設 環境硏究所 1989 環境硏究 Vol.6 No.-

광합성-광도 모델법을 이용하여 소양호의 일차 생산력 측정과 모델 변수의 동태를 조사하였다. 일차 생산력은 댐앞 지점에서 여름에 800∼1800mgC/㎥/day로 높고 겨울에 100mgC/㎥/dayd 이하로 낮게 나타났으며, Peridiniumbipes 가 밀집되는 계곡 유입부는 댐앞 지점보다 높게 나타났다. 광합성-광도 곡선의 초기 기울기(α), 광저해 계수(β) 그리고 Ik는 식품 플랑크톤의 적응 광도 변수와 신뢰성 있는 상관관계를 보여,α β 그리고 Ik가 광적옹도의 좋은 지표로 나타났다. 또한 동화 계수는 α β와 신뢰성 있는 양의 상관관계를 보였으며 이는 소양호에서 암적응된 식물플랑크톤이 α와 β가 크고 동화 계수도 크다는 것을 의미한다. α와 β는 채수수심의 광도보다 혼합층의 평균광도와 더 놓은 상관관계를 보여 식물 플랑크톤의 적응광도는 채수 수심의 광도가 아니고 혼합층의 평균 광도인 것으로 나타났다. Primary productivity was measured by phtosynthesis-irradiance (P-I) model method in a dendritic reservoir, Lake Soyang. Primary productivity was at the mesotrophicIeveI at the dam site. Productivity at the dam site was the highest in summer, 800-1800 mgC/m' / day, and low in winter, below 100. Primary productivity was higher in stream inlet regions where the migrating dinoflagellate, Peridinium lJipes, aggregates than the open water regions. P-I curves measured under the attenuated sun light or artificial light were fitted to a three parameter model. The initial slopes of P-I curves (a). the degree of photoinhiition (P), and Ik showed positive correlation with the light level that phytoplankton undergo. Therefore, α, β and Ik are good indicators of light-adaptation. AN showed positive correlation with α and β, which means that in Lake Soyang the shade-type pytoplankton has higher α and higher AN. The mean solar radiation of the mixing zone from surface to thermocline showed higher correlation with α and β than the solar radiation at the sampling depth. Therefore. it can be concluded that phytoplankton migrate through the mixing zone and phytoplankton is adapted to the mean light intensity of mixing zone, not the light intensity at the sampling depth.

팔당호의 부영양화 실태

김범철,김동섭,권오길 江原大學校 附設 環境硏究所 1990 環境硏究 Vol.7 No.-

Trophic states were surveyed in a reservoir on the Han River, Lake Paldang, receiving waters from two rivers, the North Han River and South Han River. Chlorophyll a concentration, secchi disc transparency, BOD, soluble reactive phosphorus (SRP) concentration and total phosphorus (TP) concentration were investigated at three sta-tions (dam site and the inlet region of the North Han River and the inlet region of the South Han River) and the phosphorus loading into Lake Paldang was measured. Chlorophylla, BOD, SRP and TP were highest at the inlet region of the South Han River and lowest at the inlet region of the North Han River and eutrophic level at the inlet region of the South Han River. The phosphorus loading into Lake Paldang was between the dangerous critical loading and the permissible critical loading of Vollenweider-OECD critical loading model. The phosphorus loading of the South Han River was about 2 times larger than of the North Han River.

소양호 부영양학의 연변화 추이

김범철,조규송,허우명,김동섭 江原大學校 附設 環境硏究所 1989 環境硏究 Vol.6 No.-

The trend of trophic status change in Lake Soyang from 1981 to 1989 was studied by the measurement of chlorophyll a concentration, transparaency, total phosphorus concentration, and the rate of hypolimnetic oxygen deficit rate. And the phosphorus loading from the watershed was measured monthly at the main inflowing river, Soyan River. The increasing trend of chlorophyll was clear at the rate of 0.4 /￡㎍/l/yr. The advent and expansion of Anabaena bloom was the major cause of chlorophyll, increase and transparency reduction. The rate of hypolimnetic oxygen deficit also increased from 0.032 mg Ο_(2)/cm^(2)/day in 1986 to 0066 in 1988. The trophic state of Lake Soyang can be assessed as oligotrophy before 1983, mesotrophy from 1984 to 1988, and eutrophy since 1989. Phosphorus loading from floating net fishfarms was estimated to be larger than 45% of total. The phosphorus loading from only watershed is smaller than the dangerous critical loading, but, if the fishfarms loading added, it exceeds the critical loading.

The Hypolimnetic Anexie zone and the Metalimnetic Oxygen Minimum Layer in a Deep Reservoir, Lake Soyang

김범철,조규송 江原大學校 附設 環境硏究所 1989 環境硏究 Vol.6 No.-

소양호의 용존산소 수직분포를 1985년 7월부터 1989년 7월까지 1∼2개월 간격으로 조사하였다. 전반적으로 용존산소농도가 매년 감소하는 추세를 보이고 있으며, 특히 1988년에는 심층에 무산소층이 형성되어 순환기 직전에는 저층으로부터 15m 높이까지 확대되었다. 이는 1980년대초까지 빈영양호이었던 소양호가 부영양화되고 있음을 보여주는 것이며 무산소층에서는 저층으로부터 용출된 무기인산염과 암모니아의 농도가 매우 높아 앞으로 영양염용출 증가에 의해 소양호의 부영양화는 가속될 것으로 예상된다. 또한 최근 수년간 겨울기온이 높았던 것도 수직혼합을 감소시킴으로써 용존산소 감소에 기여했을 것으로 보인다. 매년여름 수심 10∼20m에서 중층 산소최저층이 나타나고 있는데 이것은 국내 대형 저수지에서의 전형적인 분포형태인 것으로 보인다. 산소최저층이 표층의 혼합층 바로 아래에 형성되고, 수심이 깊어지면서 다시 서서히 산소가 증가하는 것으로 볼때 형성원인은 표층의 수온이 높아 산소비율이 크고 표층의 혼합층까지만 산소가 공급되기 때문인 것으로 보인다. 또한 장마철에 중층으로 유입되는 유입수에 현탁물이 많이 포함되어 있으며 산소최저층은 새로이 형성되는 중간츠으이 상부와 수심이 일치하고 있고 항상 여름의 우기에 형성되는 것으로 보아 우기의 유입수와 관련이 있을 수도 있다. The seasonal and vertical dissolved oxygen distributions were surveyed from July 1985 to July 1989 in a warm monomictic dendritic-shape reservoir, Lake Soyang. DO content showed the general trend of decrease from year to year, implying the advance of eutro· phication. HypoUmnetic anoxic zone began to develop in 1988 reaching upto 15 m from the bottom, which is an epoch·making event in Lake Soyang, well-known as a clear oligotrophich lake until early 1980s. In anoxic zone phosphate and ammonia concentration were very high, and nitrate depleted, which is expected to accelerate eutrophication of Lake Soyang. Insufficient cooling of surface waters in warm winters of 1986 to 1988 seems to have enhanced the DO decrease by reducing the duration of turnover. Metalimnetic 00 minimum layer appearing every late summer at the depth 15∼20m is a remarkable feature of DO distribution which is thought to be the typical pattern in large Korean reservoirs. The mechanism of the formation of metalimnetic oxygen minimum is further to be studied. However, it seems to be caused by the higher rate of oxygen consumption in epilimnion due to high temperature and the oxygen supply limited to only surface mixed layer, since it is formed just below the mixed layer and dissolved oxygen increase gradually in deeper layer. The intermediate current of storm runoff laden with organic debris of terrestrial origin might be the alternative cause.

국내 주요 호수의 육수학적 조사(4): 주암호

김범철,박주현,허우명,임병진,황길순,최광순,최종수 江原大學校 附設 環境硏究所 2001 環境硏究 Vol.18 No.-

In this study limnological characteristics of Lake Juam was surveyed from June 1993 to May 1994 in order to provides important information regarding water resources. Seschi disc transparency, epilimnetic chlorophyll a(chl-a), tatal nitrogen(TN), total phosphorus(TP) concentration and primary productivity were in the range of 2.0~4.5 m, 0.9~13.6 mgChl/㎥, 0.78~2.32N/l, 11~56 mgP/㎥, 270~2,160mgCm^(-2)day^(-1), respectively. On the basis of TP, Chl-a and Secchi disc depth, the trophic state of Lake Juam can be classified as mesotrophic lake. The phosphorus inputs from non-point sources are concentrated in heavy rain episodes during the monsoon season. As a result, phosphorus concentration are higher in summer than in winter. TP loading from the watershed were estimated to be 0.9 gPm^(-2)yr(-1), which correspond to a boundary of the critical loading (1.0 gPm^(-2)yr(-1), which correspond to a boundary of the critical loading (1.0 gPm^(-2)yr(-1)) for eutrophication. From the results of the algal assay, both phosphous and nitrogen act as limiting nutrients in algal growth. The seasonal succession of phytoplankton community structure in Lake Juam was similar to that observed in other temperate lakes. Diatoms(Asterionella formosa and Aulacoseira granulata var. angustissima) were dominant in spring and winter, cyanobacteria (Microcystis aeruginosa, M. sp. and M. viridis) were dominant in warm season. The organic carbon, nitrogen and phosphorus content of lake sediment were 9.5~14.0 mgC/g, 1.01~1.82 mgN/g, and 0.51~0.65 mgP/g, respectively. The allochthonous organic carbon loading from the watershed and autochthonous organic carbon loading by primary production of phytoplankton were determined to be 1,122 tC/yr and 6,718 tC/yr, respectively. To prevent eutrophication of Lake Juam, nutrient management of watershed should be focus on reduction of fertilizer application, proper treatment of manure, and conservation of topsoil as well as point source.

2차원 수리 수질모델(CE-QUAL-W2)을 이용한 소양호 수온 성층현상과 홍수기 밀도류 이동 현상의 모델링

김윤희,김범철,최광순,서동일 江原大學校 附設 環境硏究所 2001 環境硏究 Vol.18 No.-

The temporal and spatial distribution of water temperature was surveyed and simulated in a deep warm monomitic Reservoir. The great depth (maximum depth of 100 m) and wind-sheltered dendritic shape caused strong summer stratification, Turbid storm runoff during the summer monsoon formed a metalimnion of 20~40m thickness which was distinct from the clearer epilimnion and hypolimnion. The temperature distribution and the movement of density current were simulated by using the 2-dimensional hydrologic model CE-QUAL-W2. Model was calibrated with 1996 date and verified data from 1995-1999 by applying the same set of parameters and constants as in calibration. The model could simulate temperature profiles with excellent agreement. Simulation results of movement of the intermediate density current also satisfactory. It can be concluded that the CE-QUAL-W2 model is useful in the prediction of the temperature distribution and movement of density current in reservoirs, which implies merits for further employment in water quality simulation.

국내 주요호수의 육수학적 조사 (1) : 옥정호

김범철,박주현,이병진,허우명,황길순,최광순,채기숙 江原大學校 附設 環境硏究所 1998 環境硏究 Vol.15 No.-

The limnological survey of Lake Okjong was conducted for one year from June 1993 to May 1994 on the monthly basis. The loading of phosphorus, nitrogen and organic carbon from the watershed into the lake were monitored at the main in flowing sites. Secchi disc transparency , epilimnetic chlorophyll a, total nitrogen, total phosphorus concentration and primary production were in the range of 1.3~4.H m, 2.4~ 18.7 mg Chl/m³. 1.25~2.87 mg N/l, 7~65 mg P/m³, 325~2,113 mg C/m²/day, respectively. TN/Tl atomic ratio varled from 129 to 443. N/P ratio decreased in summer because phosphorus concentration was higher than in winter, while nitrogen did not vary much. The seasonal succession of phytoplankton was distinct. In winter and spring, diatoms, Aulacoseira granulata var. angustissima and Aulacoseira italica were dominant while cyanobacteria, Microcystis sp.,M. ichthyovlabe, Phormidium sp. and P.valderianum var. tenuis were dominant in warm seasons. The dominant zooplankton species were Thertmocyclops taihokuensis in warm seasons while Boosmina longirostris were dominant in cold seasons. The organic carbon, nirtogen and phosphorus content of lake sediment were 8.0~14.8, 0.59~0.71, 1.14~1.87 ng N/g, respectively. The sediment of Lake Okjong can be classified as oligohumic based on C/N ratio. The total phosphorus loading from the watershed and fishfarm were estimated to be 2.7g P/m²/yr, which far exceeded the critical loading for eutrophication. The organic carbon loading from the watershed and primary production were determined to be 998t C/yr, 6,348t C/yr, respectively. Most of organic carbon was contributed by autochthonous primary production of phytoplankton. Trophic state of Lake Okjong can be classified as eutrophic