• 한국식품과학회지
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• 제30권2호
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• pp.253-259
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• 1998

전남지역 약수의 수질특성을 파악하고자 오랫동안 음용되어온 전남 도내 47개 약수터를 대상으로 약수 중에 함유되어 있는 성분 중 가장 함유량이 많은 미네랄 성분을 분석하였으며 아울러 건강하고 맛있는 물에 대한 지표를 설정하기 위한 기본자료를 제공하고자 하였다. 17종의 미네랄 성분을 분석한 결과, 최대분포율을 보이는 주요 미네랄 성분의 평균농도(mg/L)는 Ca 3.9, K 0.78, Na 7.4, Mg 0.7, Si 9.4, Ba 0.004, Ni 0.007, F 0.16, Cl 4.9, $SO_4$ 1.5, Fe 0.001, Zn 0.002이었으며 항목별 상관성 분석결과 Na, K, Ca, Mg, $SO_4$, Cl, Ba, Ni은 통계적으로 유의한 상관성(p<0.05)을 보였다. 건강한 물의 지표인 K index와 맛있는 물의 지표인 O index를 적용한 결과 도내 약수의 98%는 건강에 도움이 되거나 맛있는 물로 확인되었고 이 중 건강에 유익하고 맛있는 그룹에 속하는 약수의 K와 O index값은 각각 6.3과 5.2로 나타났다.

• 해양환경안전학회지
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• 제20권3호
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• pp.270-276
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• 2014

Seasonal characteristics of water and sediment qualities and potential effects of the freshwater discharge from a small tide embankment interior in a coastal area in Goheung county were investigated from May to September in 2012. Chemical oxygen demand values (COD) were mostly higher than 2 mg/L in summer ebb tide, which exceed the standard value of water quality criteria II of acceptable level for aquaculture activities. Nitrogen and phosphorus were found as the limiting nutrients for algae growth in summer and fall and in spring, respectively. Nitrogen was the limiting nutrient for diatom growth in the whole studied period. The sudden high values of COD, ammonia, dissolved inorganic nitrogen (DIN), dissolved inorganic phosphorus (DIP) were found in water sample collected from station 5 which located in front of the tide embankment sluice gate during spring ebb tide. The freshwater discharge form the tide embankment interior maybe affected the survey areas during a short time interval. Mean values of eutrophication index of the surveyed coastal region in spring, summer and fall were all bigger than 1. Water quality was mostly considered at level II which acceptable for aquaculture activities. Sediment quality in this study was generally in the range of standard for fisheries environment.

• Fisheries and Aquatic Sciences
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• 제24권1호
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• pp.41-52
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• 2021

Data for fish species composition and the catch of fish species were obtained from the daily trading records for the period between April and December 2016 to 2018 at the set net fishing grounds in Yeosu Bay, Korea. The annual mean total catch was 195.8 tons, and the dominant species was the Spanish mackerel (Scomberomorus niphonius), which accounts for about 55 percent of the total catch. The catch increased in spring and autumn. Increase in spring is caused by not Spanish mackerel but other fish while the increase in autumn by Spanish mackerel. The distinct increase of the catch in summer, 2017 was due to the new recruitment of small-sized Spanish mackerel, which was probably to be from the fish population hatched in spring in the East China Sea. Our results showed a strong correlation between water temperature and catch fluctuation. The catch increases with the increase in water temperatures, and the periodic pattern of the water temperature and catch fluctuation is more consistent in the offshore waters, in which warm current flows, than in the coast waters.

• 한국수산과학회지
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• 제54권1호
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• pp.90-100
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• 2021

In the north and northeast of Cheonsu Bay, short-term fluctuations of surface water temperature are large owing to shallow water depth, weak current, and freshwater runoff. However, in the south of the bay, water temperature fluctuations are small owing to the inflow of offshore water by tidal currents. The water temperature in the north of the bay is higher in spring and summer than in the south of the bay, but lower in autumn and winter. During spring season, the fluctuation in the northern surface water temperature is the highest. The temperature fluctuations owing to tides are in phase with the tide in autumn and winter, and in the reverse phase with the tide in spring and summer. The dominant periods of water temperature fluctuations are half a day, daily, 15 days, and 1 month owing to the tide and 7 to 10 days, which are estimated based on atmospheric factors. Half a day and daily water temperature fluctuations are also highly correlated with air temperature and wind fluctuations. The sea area where water temperature fluctuations are highly correlated is divided into the north and south of the bay. The fluctuation phase is faster in the north of the bay than in the south or in the center.

• 대한환경공학회지
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• 제37권5호
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• pp.303-311
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• 2015

이 연구는 영산강 수계 중 수체를 대상으로 10종의 과불화 화합물 (perfluorinated compounds, PFCs)로 인한 오염실태를 파악하기 위한 모니터링을 수행 하였다. 시료채취는 영산강 전수계에 걸쳐 있는 총 18지점에서 이루어졌고, 5-6월인 봄철과 10월인 가을철 두 번에 걸쳐 시료가 채취되었다. 10종의 PFCs 오염물을 대상물질로 하여 분석한 결과, 물 시료 중 농도는 PFOS (perfluorooctanesulfonate)가 20.8-92.0 ng/L, PFOA (perfluorooctanoate)가 method detection limit (MDL)-28.40 ng/L로 검출되었으며 PFNA (Perfluorononanoate)가 MDL-42.20 ng/L, PFHxS (perfluorohexanesulfonate)가 MDL-11.47 ng/L로 나타났다. PFOS는 봄과 가을철 모두에서 검출빈도와 그 농도가 높았고, PFOA와 PFNA는 대체로 봄철이, PFHxS의 경우는 가을철에 검출빈도와 농도가 높은 것으로 조사되었다. 하지만 상기 4종을 제외한 다른 PFCs 화학종은 검출빈도가 낮고 매우 낮은 농도인 것으로 나타났다. 하 폐수처리장이 위치한 광주의 도심지역 수계지역의 수체 시료에서 검출된 PFCs의 농도는 타 영산강 수계내 수체 시료에 비해 상대적으로 높은 것으로 나타났다.

• Fisheries and Aquatic Sciences
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• 제23권4호
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• pp.14.1-14.14
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• 2020

We performed field measurements of the behavioral changes in cultured chub mackerel (Scomber japonicus) caused by tide-induced changes in the shapes of their small-sized tetragonal fish cages. The field measurements were conducted in two separate periods: neap tide, a period in which the shape of the fish cages was stable; and spring tide, a period in which the fish cages are significantly deformed, which was expected to have significant influences on fish behavior. In the spring tide, the cages were deformed greatly by the moving water, with different water velocities affecting the cages to different degrees; the volume loss was estimated at 4.9% and 7.3% for v = 0.114 m/s and v = 0.221 m/s, respectively. The fish exhibited significantly different behaviors between the neap tide and spring tide. During the neap tide, the fish remained in the lower part of the cage, but during the spring tide they made frequent upward and downward movements, and their horizontal distribution changed significantly due to the changes in the shape of the cage. The cage deformation during the spring tide greatly influenced the swimming behavior of fish.

• 한국환경복원기술학회지
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• 제14권1호
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• pp.121-132
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• 2011

Removal rates of $NO_3$-N and TN in the free-water surface wetland system during winter; December, January, February and March, spring and fall; April, May, October and November, and summer; Jun, July, August and September were investigated. The system was established on floodplain in the downstream reach of the Gwangju Stream in 2008. It measures 50 meters in length and 5.5 meters in width. Iris pseudacorus L. grown in pots for about two years were planted in the system. The water stream was funneled in by gravity and its effluent was discharged back in. Volumes and water quality of inflow and outflow were analyzed from December 2008 to November 2010. The inflow was averaged approximately 350 $m^3/day$ and hydraulic residence time was about 3 hours. Average influent and effluent $NO_3$-N concentration was 3.75 and 3.35 mg/L, respectively and $NO_3$-N retention was amounted to 10.6%. Influent and effluent TN concentration were averaged 4.93 and 4.30 mg/L, respectively and TN abatement reached to 12.9%. One-way ANOVA statistics claimed that the average removal rates of $NO_3$-N and TN during winter, spring and fall, and summer were not always the same (p<0.001). The t-Tests of three pairs among $NO_3$-N removal rates of winter, spring and fall, and summer illustrated that the removal rates of winter ($5.04{\pm}1.94$), spring and fall ($10.53{\pm}2.24$), and summer ($18.61{\pm}2.26$) were significantly different each others (p<0.001). Among TN removal rates, the three pairs of t-Tests of three seasons showed that the removal rates of winter ($5.21{\pm}2.51$), spring and fall ($11.71{\pm}3.12$), and summer ($21.53{\pm}4.86$) were significantly different from each others (p<0.001).

• 환경생물
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• 제40권1호
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• pp.70-86
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• 2022

서해 남부 안마군도 주변 해역 식물플랑크톤 군집의 계절 동태를 파악하기 위하여 2020년 봄부터 2021년 겨울까지 소형 해양조사선 에드오션호를 이용하여 21개 정점의 표층과 저층 해수를 대상으로 현장조사를 하였다. 결과, 출현한 식물플랑크톤 종은 52속 87종으로, 규조류가 67.8%, 와편모조류가 26.5%, 규질편모조류가 3.5%, 그리고 은편모조류 및 유글레나조류가 각 1.1%를 차지하였다. 계절별로 출현 종은 봄에 단순하였고, 겨울에 상대적으로 다양하였다. 표층 현존량은 여름 28.8±30.1 cells mL^-1로 낮았고, 봄 87.0±65.1 cells mL^-1로 높았다. 식물플랑크톤 군집은 연중 규조류가 80% 이상 높은 점유율을 나타내었고, 우점종은 Skeletonema costatum-ls가 봄과 겨울에 60% 이상 극우점을 보였고, 여름과 가을 각 34.6%와 24.2%로 최우점하였다. 군집구조 특성을 나타내는 다양도 지수는 현존량과 다르게 가을에 2.79±0.45로 높았고, 봄에 1.82±0.18로 낮았다. 그러나 우점도 지수는 봄에 0.86±0.08로 높았고, 가을에 0.44±0.13로 낮았다. 환경인자 및 식물플랑크톤 군집 관련 인자를 이용한 주성분 분석 결과, 식물플랑크톤 군집을 통해 본 안마군도 주변 해역의 생물해양학적 환경 특성은 상대적 개방해역 및 조석 혼합 등 해수 혼합에 의한 해저 퇴적층에서 공급되는 영양염 등에 의해 지배되는 것으로 추정되었다.

• 한국농림기상학회지
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• 제25권3호
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• pp.218-225
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• 2023

영농형 태양광 시스템은 노지 작물 경작과 동일한 토지 상부에 설치된 태양광 패널을 통한 발전을 동시에 하는 시스템이다. 지금까지 영농형 태양광은 에너지와 식량의 양자구도로만 집중되어있다. 영농환경 중 하나인 토양수분은 강우 또는 관개수로 증발 및 유출⋅침투로 손실된 수분을 공급받아 노지 작물 생산에 기여한다. 본 연구는 식량, 에너지와 함께 물의 개념을 포함하여 영농형 태양광 시설을 보고자 하였으며, 미기상 관측을 통해 봄 기간 동안 휴경논에서 영농형 태양광 시설 하부의 토양수분과 지온의 변화를 분석하였다. 영농형 태양광 하부는 패널로 인한 부분차광 조건으로 지면에 입사되는 광 에너지량이 감소하여 지온이 낮아질 뿐만 아니라 토양수분 손실이 적어 대조구인 노지에 비해 습윤한 조건을 보인다. 또한, 태양광 하부는 에너지 제한 환경이며, 상대적으로 지온이 높은 노지는 수분 제한 환경으로 설명된다. 노지와 태양광 하부의 상이한 토양수분 환경은 필연적으로 작물에 영향을 미칠 것이며, 농업 환경과 농촌 경제를 고려한 지속가능한 대처가 필요하겠다.

• 수산해양기술연구
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• 제50권4호
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• pp.633-642
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• 2014

Monthly variation in abundance and species composition of the fishes were investigated based on specimens collected by gill net in coastal water of Yeosu from October, 2009 and February, May, August, 2010. The collected fishes were 1,529 individuals (183,840g) of the total, identified into 6 orders, 16 families and 24 species. The most dominant order fish was Perciformes comprised 9 species, 7 families, and followed Pleuronectiformes comprised 5 species, 3 families, Scorpaeniformes comprised 5 species, 2 families. These 3 orders constituted 81.1% of the total collected fish. During the study, most dominant species was Hexagrammos otakii accounted for 189 individuals (12.4%) of the total, followed by Lateolabrax japonicus 165 individuals (10.8%), Hexagrammos agrammus 154 individuals (10.0%). The fish was collected by a gill net in coastal water of Yeosu from October, 2009 and February, May, August, 2010, the diversity index of the fishes was 2.09~2.66, which was the highest in August, 2010 and the lowest in February, 2010. The evenness index of them was 0.84~0.89, which was the highest in August, 2010 and the lowest in February, 2010 and the richness index of them was 2.02~3.14, which was the highest in October, 2009 and the lowest in February, 2010. The analyzed species diversity index by the each stations was 2.47~2.66 and the evenness index was 0.84~0.90 and the richness index 2.99~3.37. The similarity of community structure per season was very high which was the least in spring and fall. In addition, the community structure was very similar in state 3 and 2 out of each stations.