• Journal of Environmental Health Sciences
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• v.11 no.1
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• pp.15-28
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• 1985

In order to analyze the water quality in artificial lakes in Chonnam area, a chemical and biological examination of Dongbock Lake and Changsung Lake was conducted from September to December 1983 and May 1984. A summary of the surveyed results is as follows 1. In Dongbock Lake, pH ranged from 7.2-8.1, D.O.: 8.2-12.6mg/l, B.O.D.: 4.4-22.1 mg/l, C.O.D.: 1.0-3.4rag/l, Cl$^-$: 5.9-11.9mg/l, Total-P: 0.001-0.071 mg/l, and Total -N: 0.016-0.697 mg/l, respectively. 2. In Changsung Lake, pH ranged from 7.2-8.1, D.O.: 8.1-9.8mg/l, B.O.D.: 0.9-2.9mg/l, C.O.D.: 1.9-3.4mg/l. Total- P: 0.006-0.016mg/l and Total -N:0.006-0.033mg/l, respectively. 3. The Phytoplankton identified in this investigation were distributed in a total of 46 genera and 76 spedes in Dongbock Lake 37 genera and 45 species in Changsung Lake. 4. In Dongbock Lake, it was found that the dominant algae were Melosira sp., Microcystis sp. and Synedra sp. in September Melosira sp. and Microcytis sp. in October, but Cymbella sp., Naviculla sp. and Nitzschis sp. were also observed in OctoberAsterionella sp., Melosira sp. and Microsystis sp. in November and Melosira sp., Asterionella sp sp. and Synedra sp. in December 1983. 5. In Changsung Lake, it was found that the dominant algae were Melosira sp., Lyngrbya sp. and Microcystis in September Melosira sp. and Synedra sp. in October and November and Melosira sp., Lyngbya sp. and Asterionella sp. in December 1983. The dominant algae were Melosira sp., Lyngbya sp. and Euglena sp. in May 1984. 6. It was found that the dominant algae in both Dongbock and Changsung Lakes were Microcystis sp., Melosira sp. and Asterionella sp.. Which are strongly related with water-bloom. Therefore, it could be suggested that the eutrophication phenomena is going to occur very easily in Dongbock Lake and possibly in Changsung Lake.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.3
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• pp.263-269
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• 1995

To determine the autochthonous COD caused by the production of phytoplankton, three different methods were used simultaneously utilizing several environmental factors and applied to the Nakdong Estuary. From the estimation of the tropic state index, tropic level in the Nakdong Estuary was found to be in excess of eutrophication level at all area studied. The percentage of autochthonous COD in total COD was largest in summer and in station No. 6 $(43.5\%)$. Using of the relationship between COD and salinity was not appropriate tov the evaluation of the autochthonous COD due to discrepancy with other tesulfs evaluated. However, the evaluations of autochthonous COD obtained from the $\DeltaCOO$ and the relationship between COD and chl.a were found to be proper methods, resulting in a relative error less than $20\%$ for all of the area investigated.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.8 no.4
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• pp.938-945
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• 2004

On the relationship between the red tide occurrence and the oceanographic factors in the middle coastal area in the South Sea of Korea, the favorable oceanographic conditions for the red tide formation are considered as follows； the calm weather increases sea water temperature in summer and early-fall which the red tide occurs frequently, and the heavy precipitation brings some riverine water to ween: low salinity, high suspended solid, low phosphorus and high nitrogen, respectively. We decided the potential areas in the coastal zones vulnerable to the red tide occurrence based on the limited factors controlling the growth of phytoplankton. By using GIS through the overlap for three subject figures (phosphorus, nitrogen and suspended solids), it was founded that the potential areas are the Yeosu∼Dolsan coast, the Gamak bay, the Namhae coast, the Narodo coast, the Goheung and Deukryang bay. This result has very well coincided to the results of the satellite and in-situ data.

• Ocean and Polar Research
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• v.43 no.1
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• pp.31-43
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• 2021

To understand the temporal variation of prokaryotic communities in a temperate coastal area, prokaryotic abundance, activity, and community composition were investigated every week for over a year at a coastal monitoring station of Yeong-do, Busan. The prokaryotic abundances fluctuated about 10 times, ranging from 2.0 to 20.1 × 10⁵ cells mL^-1 and tended to be high in spring when phytoplankton bloom occurred. The prokaryotic thymidine incorporation rates (TTI) varied in a low range between 0.2 and 11.5 pmol L^-1 h^-1 in winter. However, in summer, TTI were increased up to a range of 8.3 to 17.4 pmol L^-1 h^-1, showing an increasing pattern in summer. During the study period, Alphaproteobacteria was the most dominant class for most of the year, followed by Flavobacteria. While the seasonal variation of prokaryotic composition was not apparent at the class level, many prokaryotic species showed a distinct temporal or seasonal variation for the year. In the coastal site, prokaryotic biomass and activity did not show significant correlations with temperature and chlorophyll-a, which are well known to regulate prokaryotic growth in marine environments, suggesting that the study area may be affected by diverse sources of organic matter for their growth.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.14 no.3
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• pp.155-162
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• 2009

To characterize the initiation, propagation and termination of Cochlodinium polykrikoides blooms in the southeast coastal waters of Korea, 2008, we analyzed the data set of phytoplankton composition, physical and chemical water properties, and meterological data. C. polykrikoides bloom in 2008 were long lasting and restricted to the coastal area with a low density. Our results indicate that C. polykrikoides blooms were affected by the atypical cold waters occurring in east-south coastal water in the early July. The cold water masses probably protected the free living cells of C. polykrikoides from entering into the coastal area from offshore waters as a pelagic seed population. The low density blooms of small scale established possibly by the germination of C. polykrikoides cyst in shallow coastal bottom could have not spread over because of the weak wind and low nutrient concentrations caused by severe drought in July and September.

• Journal of Ecology and Environment
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• v.48 no.1
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• pp.1-7
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• 2024

Background: Available publications (e.g., theses, scientific reports, books and papers) about the elements of the Egyptian biodiversity during 2000-2018 were collected in a progress scientific report. The publications reported in this bibliography were collected from various sources including: site of the Egyptian Universities Libraries Consortium Portal, accounts of the biodiversity specialists on Research gate, direct contact with the national experts of the Egyptian biodiversity, libraries of some universities and research centers and others. The elements of the Egyptian biodiversity are classified into different categories. Results: Up till now, a total of 20,521 species were recorded in Egypt, of which insects have the highest contribution (48.7%), followed by fungi (12.1%) and vascular plants (11.5%). In a descending order, each of amphibians, viruses, reptiles, mammals, cyanobacteria, bryophytes, and bacteria have a minor contribution (< 1%). Based on the available data, Egyptian biodiversity contributes 1.3% of the world biota, although its area contributes only 0.7% of the world area. At a global scale, the most represented groups are algae (12.22% of the world figure), followed by cyanobacteria (6.08%) and birds (4.70%). On the other hand, the less represented are amphibians (0.14% of the world figure), flora (0.84%) and insects (1.00%). Conclusions: Some suggestions are recommended for preparing a phytoplankton checklist based on the rich available publications; further studies should be carried out on the lichen biodiversity in order to prepare acceptable verified checklist for this important group. In addition, paleo-biologists should work together to publish a book dealing with the Egyptian paleo-biology, such studies will lead to high ranking the Egyptian biodiversity.

• Journal of the Korean Society for Marine Environment & Energy
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• v.20 no.1
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• pp.1-11
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• 2017

Nakdong River Estuary is affected by the dam, barrage construction and dredge and reclaim worked artificially. So, we have studied the area input both freshwater and sea water to understand marine environment of Nakdong River estuary related to the effect of artificial work from 2013 to 2015. As a result, The discharge flow to the estuary remarkably decreased before barrage construction and the average of salinity at the estuary increased. So, the brackish water zone reduced under the influence of decreased discharge flow. The major sources of nitrate and silicate were freshwater, phosphate supplied from bottom and the open sea water. The concentration of phosphate and dissolved oxygen (DO) decreased remarkably in spring and summer. we investigated that phosphate in freshwater was removed under the influence of the estuary dam and phosphate in sea water was removed under the influence of phytoplankton. The low concentration of DO was due to decomposition of the organic compound by microorganism after phytoplankton blooms. Generally, the concentrations of chlorophyll-a in summer was higher than spring and fall. Therefore, the change of ecosystem in Nakdong river estuary was due to decrease of freshwater influx, the other change is facing because of the barrage.

• Journal of the Korean Society for Marine Environment & Energy
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• v.11 no.2
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• pp.105-112
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• 2008

The surface and bottom water were sampling in ten stations of the coastal area of Chagwi-Do, Jeju Island, which was repeated 6 times in several different months(September, November, 2004 and March, May, August, and November 2005) in order to examine the physico-chemical characteristics of water. The temperature varied by approximately $16^{\circ}C$, ranging somewhere between 1$12.2^{\circ}C$ and $28.9^{\circ}C$. Specifically, the temperature of bottom water was $13^{\circ}C$, implying the emergence of low temperature water. The salinity ranged from 30.2 to 34.9%o, and the lowest salinity in August may be attributable to the effect of land-based water. N/P ratio, the growth factor of phytoplankton, ranged from 5 to 76, which varied depending on the season and station. The ratio, however, was over 22 on the average, suggesting that phosphate phosphorus is an factor that restricts the growth of phytoplankton. TOC in the concentration of organic carbon ranged between $92.5{\mu}M$ and $438.3{\mu}M$, and the mean was $217{\mu}M$. DOC ranged from $82.5{\mu}M$ to $299.2{\mu}M$, and the mean was $130{\mu}M$. The ratio of DOC/POC was 60% with abundant dissolved organic carbon.

• Journal of Aquaculture
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• v.15 no.1
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• pp.61-68
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• 2002

A comparative study on the effect of rearing depths at 2 (surface) and 5 (bottom) m on growth of the scallop was undertaken in Nam-myeon coastal area during June to December, 1997. There were very little difference in the levels of temperature (12.2 ~24.5$^{\circ}C$), salinity (27.3 ~33.1$\textperthousand) and dissolved oxygen (>7.05 mg/l) at a given month. But the chlorophyll level fluctuated between 1.2 and 11.0 $\mu g/l$ at the surface but below 2 $\mu g/l$ at the bosom. Highest phytoplankton density occurred in August and Ceratium dominated it during the period from June to October. Mean growth of the bay scallop at surface and bottom for the six months rearing period was as follows; 0.19 and 0.16 mm/day for shell height, and 0.16 and 0.12 g/day for total weight. Maximum predicted values of shell height calculated by von Bertalanffy growth model were 52.62 mm for the surface and 46.73 mm for the bottom reared scallop. Survival of the scallop was higher (80 %) for the surface group than that at the bottom (60%).

• Ocean and Polar Research
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• v.27 no.3
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• pp.251-263
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• 2005

In order to study changes in the marine ecosystem of the East China Sea derived by the global warming and construction of the Three Gorges Dam in the middle of the Changjiang, temperature, salinity, nutrients, and chlorophyll-a were studied intensively in the northern part of the East China Sea during the summer of 2003 and spring of 2004. According to the previous studies, the upwelling of the Kuroshio Current and the Changjiang resulted in a major inputs of nutrients in the East China Sea, but these two inputs may not contribute gently to a build up of nutrients in the northern East China Sea. In spring, relatively high concentrations of nitrates and phosphates were observed in the western part of the study area, which resulted from the supply of high concentrations of nutrients showing up in the surface waters as a result of vertical mixing from the ocean bottom. The concentrations of nitrates and phosphates observed in summer were lower than those in spring, since the surface waters were well stratified by the larger discharge of fresh water from the Changjiang in summer. The surface nitrate/phosphate ratios ranged from 1.3 to 16 in spring and from 1.1 to 15 in summer and were lower than the Redfield ratio of 16, indicating that the growth of phytoplankton is limited by nitrogen. This results are contrary to the previous results, in which the growth of phytoplankton was limited by phosphate in the East China Sea. The reason for this contrary result is that most nutrients in the surface waters are supplied by vertical mixing from the bottom waters with low nitrate/phosphate ratios, not directly influenced by the Changjiang with high nitrate/phosphate ratios. The depth-integrated chlorophyll observed in summer was similar to the previous results, but those measured in spring were almost twice as high as those found in previous results. The depth-integrated chlorophyll in spring was higher than that of summer, which results from high concentrations of nitrates and phosphates in the surface waters in spring due to active vertical mixing.