광양만에서 호안 건설 후 조간대 퇴적물의 분포 및 변화를 조사하기 위하여 표층 퇴적물의 조직 특성과 퇴적률에 대한 모니터링을 실시하였다. 퇴적물의 평균 입도는 가을에 조립하고 겨울, 봄, 여름으로 갈수록 세립해지며, 여름에는 초기에 일시적으로 조립한 후 세립해지는 계절적 변화를 보였다. 퇴적률은 봄에 퇴적되고 여름과 가을에 주로 침식되어 호안이 건설퇴기 이전인 2001-2003년 동안 관측한 결과와 매우 비슷한 양상을 보였다. 그러나 연평균 퇴적률은 북측 조간대에서는 2001-2003년 동안 관측한 결과와 유사한 경향을 보였으나, 주변에 호안이 건설된 서측 조간대는 퇴적 환경에서 침식 환경으로 변화된 양상을 보였다. 이와 같은 퇴적 환경의 변화는 아마도 호안 건설에 따른 수류의 변형에 기인하는 것으로 판단된다.
본 연구는 전라남도 광양만의 6개 임해매립지 식재지반의 토양환경 특성을 조사분석하였다. 토심이 깊어짐에 따른 토양성질의 수직적 특성은 각 식재지반별로 다르게 나타났다. 토양성질의 수직적 특성에 영향을 미치는 요인은 개토와 준설토의 이질서, 토양의 물리. 화학성의 교란, 지반하부에 잔존하는 염류의 이동, 유기물의 이동과 강우나 가뭄 등이었다. 수목생 상 유리한 식재지반은 식재지반의 높이가 낮은 곳보다 높은 성토지역이었으며, 이것은 토양의 물리. 화학적 교란과 지하부의 염류로부터 안전성이 높기때문이었다. 조경식물의 생육상 불리한 토양성질들은 토성의 이질서, 토양의 경화, 알칼리성 염류토양, 높은 ECe, Na, K. 저농도의 Ca, Mg, T-C등이었으며, 이러한 토양성질들은 표토보다는 지하의 근권부에 주로 분포하여 있었다. 따라서 임해매립지 식재지반 조성시에는 토양의 성질이 교란되지 않은 방법이 모색되어야 하며, 조경수목의 생육에 관련된 토양환경조사는 지하근권부 이하까지 정밀하게 조사. 분석하여야 할 것으로 사료되었다. 사료되었다.
Feeding habits of Lateolabrax Japonicus collected from the eelgrass bed in Kwangyang Bay from January 1994 to December 1994 were studied. L. Japonicus was a carnivore which consumed mainly amphipods (gammarid amphipods and caprellid amphipods), crabs, caridean shrimps and copepods. Its diets included small quantities of fishes, mysids, polychaetes, tanaids and isopods. Three distinct ontogenetic feeding groups were noted : (1) 1~2 cm SL individuals preyed heavily on copepods. (2) 2~15 cm SL individuals preyed heavily on amphipods. (3) individuals over 15 cm SL preyed heavily on crabs, caridean shrimps and fishes. L. Japonicus showed seasonal changes in prey composition. These changes were not caused by seasonal changes in food availability, but by changes in the size composition of L. Japonicus occurred in the eelgrass bed.
Sea water samples collected in August, 1994 from 20 stations in the Kwangyang Bay were analyzed by gas chromatography/mass spectrometry-selected ion monitoring (GC/MS-SIM) to investigate persistence and distribution pattern of four organophosphorus pesticides (DDVP, Diazinon, IBP, EDDP). Except for IBP, the contamination by DDVP, Diazinon, and EDDP in marine aquatic environment in Korea has not been reported previously. In this study, however, all these four pesticides were detected in all stations (except DDVP) and their concentrations were in ng/L level. The concentrations ranged from detection limit to 15.3ng/L for DDVP, 1.8-27.7ng/L for Diazinon, 7.3-63.5ng/L for IBP, and 22.2-1100.1ng/L for EDDP. It is noteworthy that the measured concentrations of IBP and EDDP in this study would be much lower than usual, since the use of IBP and EDDP was less than 50% of average annual consumption due to unusually dry and hot weather condition in the summer of 1994. It was very surprising to find that the highest concentrations of organophosphorus pesticides were observed at stations near Daesa Streamlet instead of Seomjin River, which has more point source of the pesticides. This result suggests that the small river discharge during heavy rain period in summer can give harmful effect on marine biota (both wild and aqua-cultured) with its organophosphorus pesticide residue, despite of their short residence time in aquatic environment. In order to protect the marine life properly from acute toxicity of the organophosphorus pesticides, it needs to be emphasized that monitoring the level of agricultural pesticides in river run-off should be done during active consumption period rather at regular intervals.
Physicochemical characteristics of Kwangyang Bay, have been investigated on the effects of inputting rivers just after rainy season in summer 2003. The results ranged from 4.96~8.01 mg/L for DO, 1.16~3.09 mg/L for COD, 7.21~67.71 μM for DIN and 0.12~121.84 μM for phosphate. The COD of Yeosu Area was 1.19~3.09 ㎎/L, Kwangyang Area was 1.23~2.76 ㎎/L. The COD of Wallae cheon in Yeosu Area was 3.09 ㎎/L and Donghoan in Kwangyang Area was 2.76 ㎎/L. The reason of high COD might be industrial sewage of organic chemical plants and iron foundry. DIN of Yeosu Area and Kwangyang Area were 7.21~63.43 μM and 8.43~67.71 μM respectively. The average phosphate of Yeosu Area was 23.65 μM. The source of phosphate might be industrial sewages of fertilizer plant and phosphate gypsum stocked with high amounts. The metal concentrations were measured in the range of 1.01~175.10 ㎍/L for Cu, 0.13~1.78 ㎍/L for Cd, 1.13~5.21 ㎍/L for Pb, 1.58~13.57 ㎍/L for Cr and 1.07~20.68 ㎍/L for As. The average Cu concentration was 78.99 ㎍/L in Kwangyang Area. The source of Cu might be industrial sewage of iron foundry. The average Cr concentration of Yeosu Area was 9.07 ㎍/L. That is 2 times higher than Kwangyang Bay 5.74 ㎍/L, because of sewage of chemical plants.
Polycyclic aromatic hydrocarbons(PAHs) in sediments of Kwangyang bay on Korea, have been investigated by gas chromatography-mass spectrometery (GC/MS). The average content of total PAHs in all samples was 2,211ppb, and the range was from 36 to 22,699ppb. The higher concentrations were found in sediment sampled near Kwangyang iron processing plant, Taeindo. The resulting distributions of PAHs according to the number of aromatic ring and molecular ratios of specific aromatic compounds (phenanthrene, anthracene, fluoranthene and pyrene) have been discussed in terms of sample location, origin of the organic matter. Four, five and six rings of PAHs were mainly found near to Kwangyang iron processing plant, and three and four rings near to Yeosu chemical kombinat. This result typically indicated the local characteristics, depending on the origin of PAHs.
This study presents an investigation of the changes of the currents in Kwangyang Bay due to the construction of harbor, reclamation and coastal developments. Currents were simulated by the numerical experiments with a diagnostic multi-level model and using the seasonal oceanographic data of temperature, salinity and ocean current. The values of kinetic and potential energies for the currents were calculated in cases of three topographical changes; before coastal developments, the existing state and after completion of the development project in Kwangyang Bay. The changes of currents due to the coastal developments are as follow; Kinetic energies of tide induced residual currents and wind driven currents decreased by 35~40 percent and 5 percent respectively, however those of density currents increased by 10 percent since the decrease of the coastal areas. Kinetic energy of residual currents including tide induced residual currents, density currents and wind driven currents reduced by 10 percent compared with before the coastal developments. Decrease of current velocity was greatest in summer. Therefore, in summer it was assumed that the Kwangyang Bay is more easily polluted by stratification and decrease of residual current than before the coastal developments carried out.
Numerical simulation model using nesting method and considering topographic features was developed to predict atmospheric environments, atmospheric flow, temperature and diffusion of air pollutants in Kwangyang bay where having complex areas of point sources, Korea.
In addition, developed simulation model was used tracing of spreading range of pollutants when a gas leaks suddenly from Yeo-cheon industrial complex.
By comparing the measured and calculated data on atmospheric flow, temperature and diffusion of air pollutants, the results showed that this model can be well applied and complicated topography affected the diffusion of air pollutants.