• 한국환경과학회지
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• 제23권7호
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• pp.1375-1383
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• 2014

Total organic carbon(TOC), Total nitrogen(TN), and carbon and nitrogen stable isotopes were measured in the sediment and suspended parties in fresh lake water and saline estuarine water to determine the sources of Particulate organic matter(POM) in the sediments of the Youngsan river estuary. POM in the freshwater discharge water was mostly phytoplankton origin with little trace of terrestrial plants. POM from phytoplankton blooms formed in estuarine water in response to the nutrient enriched freshwater discharges was the most important sources of POM in the sediment near the dike, comprising more than 40% of the total organic matter. POM from freshwater phytoplankton and oceanic phytoplankton were also important sources of the sediment POM, and their contributions varied with the distances from the dike. Contribution of freshwater phytoplankton to sediment POM decreased from the dike to the outside of the estuary.

• Ocean and Polar Research
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• 제32권3호
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• pp.309-319
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• 2010

To assess community structure and diversity of archaea, a clone sequencing analysis based on an archaeal 16S rRNA gene was conducted at three sediment depths of the continental slope and Ulleung Basin in the East Sea. A total of 311 and 342 clones were sequenced at the slope and basin sites, respectively. Marine Group I, which is known as the ammonia oxidizers, appeared to predominate in the surface sediment of both sites (97.3% at slope, 88.5% at basin). In the anoxic subsurface sediment of the slope and basin, the predominant archaeal group differed noticeably. Marine Benthic Group B dominated in the subsurface sediment of the slope. Marine Benthic Group D and Miscellaneous Crenarchaeotal Group were the second largest archaeal group at 8-9 cm and 18-19 cm depth, respectively. Marine Benthic Group C of Crenarchaeota occupied the highest proportion by accounting for more than 60% of total clones in the subsurface sediments of the basin site. While archaeal groups that use metal oxide as an electron acceptor were relatively more abundant at the basin sites with manganese (Mn) oxide-enriched surface sediment, archaeal groups related to the sulfur cycle were more abundant in the sulfidogenic sediments of the slope. Overall results indicate that archaeal communities in the Ulleung Basin show clear spatial variation with depth and sites according to geochemical properties the sediment. Archaeal communities also seem to play a significant role in the biogeochemical carbon (C), nitrogen (N), sulfur (S), and metal cycles at each site.

• 자원환경지질
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• 제33권4호
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• pp.261-271
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• 2000

In order to evaluate the environmental impact of U anormaly in the drainage system around the Shinbo talc mine area, U contents, their distribution patterns, bioaccumulation and a-radioactivity in stream water, stream sediments and aquatic organisms were investigated. The U contents of stream water attenuated with increasing distance from the mine area. The same attenuation pattern is shown in stream sediments from mine to 0.75 km downstream, although these contain highly enriched U contents (24~83 mg/kg) comparing with the international average concentration of surface soils (0.79~11 mg/kg). However, U content increases abruptly in sediment at 1.5 km downstream, probably due to detrital migration and rediposition of U enriched sediments. Futhermore, enriched U in downstream sediments occur in high proportions of carbonate and Fe-Mn oxide bounded forms, which show high potential of a secondary pollution source. For aquatic organisms, bio accumulation degree of U are in the order: aquatic larvae>black snail>mountain frog>crawfish. Cultured trout by the U enrich groundwater (387 ${\mu}g$/l) shows U accumulation in the part of branchia (CRs 5.25) and bones (CRs 11.2) but not in flesh (CRs 0.03). Total a-radioactivity have been measured in the level as 0.47 nCi/l for groundwater, 2.94~18 nCi/kg${\cdot}$DW for organisms and 93~328 nCi/kg${\cdot}$DW for sediments.

• 한국지구과학회지
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• 제33권6호
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• pp.481-496
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• 2012

제주도 주변 대륙붕해역에 분포하는 퇴적물의 기원지를 해석하기 위해 표층퇴적물의 희토류원소(REE), 주성분 및 미량원소, Sr-Nd 동위원소비를 분석하였다. 퇴적물의 화학원소에 근거한 변질지수(CIA)는 44.2-68.9(av.59.4)의 범위를 보이며 황하강퇴적물과 유사하였다. 연구지역 퇴적물을 콘드라이트로 표준화한 REE 패턴에서 대부분 LREE가 부화된($La_{(N)}/Sm_{(N)}$ >3) 작은 Eu 부(-) 이상을 가지는 전형적인 셰일의 희토류원소의 패턴을 나타낸다. UCC로 표준화한 REE 패턴에서 연구지역 남서쪽 외해지역의 퇴적물 시료들은 황하나 금강기원 퇴적물보다 양자강퇴적물과 유사한 높은 희토류원소함량과 위로 볼록한 REE 패턴을 보여 양자강기원 부유물질이 제주도 서쪽해역까지 운반되고 있음을 의미한다. $^{87}Sr/^{86}Sr$ 동위원소비와 ${\varepsilon}_{Nd}(0)$의 구분지수는 연구지역 퇴적물의 기원지를 밝히는데 지시자로 제시할 수 있었다. 연구지역의 서쪽과 북서쪽에 분포하는 대부분의 퇴적물은 황하강 퇴적물 주위에 밀집 분포하는 특징을 보이고, 양자강 하구역과 가까운 남서쪽지역의 퇴적물들은 양자강 수중삼각주 퇴적물과 유사성을 보였다. 반면 제주도 북동쪽지역의 퇴적물은 중국의 강기원 퇴적물과는 다른 지역에 위치하는 특징을 보여, 따라서 제주도 주변해역은 복합기원 퇴적물이 집적되고 있음을 의미한다.

• 미생물학회지
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• 제38권2호
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• pp.119-126
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• 2002

심해와 연안의 서로 다른 해양퇴적토 환경에서 ATP농도를 이용한 총 미생물 생체량을 측정하였다. 표층 ATP의 분포는 연안역에서 가장 높았으며, 육지로부터 멀어질수록 감소하였다. 또한 수직적으로는 깊이에 따라 급격히 감소하는 양상을 나타내, 저층의 생태계가 수층으로 부터의 영양원 공급에 의해 일차적으로 조절되고 있는 것으로 나타났다. 한편, 유기물은 퇴적물로의 흡착으로 인해 환경 내 체류시간이 길어짐으로 인해, 유기탄소의 함량 변화가 ATP에 비해 급격히 일어나지 않았으며, 특히, 연안퇴적토의 경우 유기탄소의 함량 변화에 비해 ATP의 농도변화가 일정하게 나타나 두 변수간의 유의성 이 없는 것으로 나타났다. 이러한 결과는 분해가능한 유기물의 공급이 많은 연안퇴적토의 경우, 영양원에 의한 조절보다는 상위영양단계의 포식활동이 미생물의 생체량을 최종적으로 조절하는 요인으로 작용하기 때문 인 것으로 사료된다. 지역분포 특성 및 수직적 분포 특성으로부터 ATP는 서로 다른 저서 생태환경의 생체량 분석을 위한 일차적 인 도구로 유용하게 쓰일 수 있는 것으로 나타났다.

• Ocean and Polar Research
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• 제25권1호
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• pp.1-7
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• 2003

The purpose of this study was to determine changes in the growth rates and the degree of shell bioerosion exhibited by endolithic organisms of the Japanese scallop family, Patinopecten (Mizuhopecten) yessoensis, on the coast of Furugelm Island (Peter the Great Bay, northwest of East Sea = Sea of Japan) over the last three decades. The areas studied are affected by lumen (Tumangang) River run-off, which is enriched by organic matter and polluting agents. It was found that the linear growth rates of the Japanese scallops living along the coasts of Furugelm Island have decreased over the last three decades. The degree of bioerosion of scallop shells has significantly increased for the same period. These phenomena may be explained by a gradual increase in bottom sediment silting, organic enrichment and pollution of the areas being studied. It was found that the degree of scallop shell bioerosion increased with the scallop's age. At present, In each age group, the shells of the scallops sampled from the muddy sand showed greater erosion than the shells of individuals collected from the sandy substrate.

• 자원환경지질
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• 제32권1호
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• pp.63-72
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• 1999

In order to examine the contamination levels of trace elements in stream sediments in the Chungnam coal mine area, stream sediment and water samples were collected and analyzed for trace elements. The pH of stream water was neutral or weak-alkaline and the mobility of metal in stream sediments was supposed to be low. From the result of cluster analysis, non-polluted sampling stations can be distinguished from polluted sampling stations influenced by mining activities. The trace element concentrations in sediments from non-polluted zone were considered to be the natural backround concentrations of this area. The trace element concentrations in sediment samples from the mining area were higher than those from non-polluted area, and contaminated area of enriched trace element levels need to be properly managed. From the results of discriminant and regression analyses, concentrations of Cd, Cu, Pb AND zN and predicted values of Be, Mo, and Ni in Chungnam coal mine area were found to be lower than those in metal mining areas in Korea.

• 한국수산과학회지
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• 제40권5호
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• pp.282-287
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• 2007

Chloroanilines are aromatic amines used as intermediate products in the synthesis of herbicides, azo-dyes, and pharmaceuticals. 3,4-dichloroaniline (DCA) is the degradation product of some herbicides (diuron, propanil, and linuron) and of trichlorocarbanilide, a chemical used as an active agent in the cosmetic industry. The compound, however, is considered a potential pollutant due to its toxicity and recalcitrant property to humans and other species. With the increasing necessity for bioremediation, we sought to isolate bacteria that degraded 3,4-DCA. A bacterium capable of growth on 3,4-DCA as the sole carbon source was isolated from seaside sediment using a dilution method with a culture enriched in 3,4-DCA. The isolated strain, YM-7 was identified to be Pseudomonas sp. The isolated strain was also able to degrade other chloroaniline compounds. The isolated strain showed a high level of catechol 2,3-dioxygenase activity on exposure to 3,4-DCA, suggesting that this enzyme is an important factor in 3,4-DCA degradation. The activity toward 4-methylcatechol was 53.1% that of catechol, while the activity toward 3-methylcatechol, 4-chlorocatechol and 4,5-chlorocatechol was 18.1, 33.1, and 6.9%, respectively.

• 한국환경과학회지
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• 제8권5호
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• pp.593-600
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• 1999

In order to determine the changes of sediment facies and metal levels in surface sediments after the construction of Shiwha Lake, surface sediments were sampled at 8 sites located on the main channel monthly from June, 1995 to August, 1996 and analysed for 12 metals (Al, Fe, Mn, V, Cr, Co, Ni, Cu, Zn, Cd, As and Pb) by ICP/AES and ICP/MS. Two groups of sampling sites(the inner lake with 3 sites and the outer lake with 5 sites) are subdivided by the surface morphology ; the inner lake is a shallow channel area with a gentle slope, while the outer lake is relatively deep and wide channel with a steep slope which has many small distributaries. After the construction of dam, fine terrestrial materials were deposited near the outer lake, which resulted in the change of major sediment facies from sandy silt to mud. With the deposition of fine sediments in the outer lake, anoxic water column induced the formation of sulfide compounds with Cu, Cd, Zn and part of Pb. Metal (Cr, Ni, Cu, Zn and Cd) contents in sediments increased up to twice within 2 years after the construction of dam. This is due to the direct input of industrial and municipal wastes into the lake and the accumulation of metals within the lake. In addition, frequent resuspension of contaminated sediments in a shallow part of the lake may make metal-enriched materials transport near the outer lake with fine terrestrial materials. As the enrichment of Cu, Zn, Cd and part of Pb in the Shiwha Lake may be related to the formation of unstable sulfide compounds by sulfate reduction in anoxic water or sediment column, the effect of mixing with open coastal seawater is discussed.

• Journal of the korean society of oceanography
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• 제34권2호
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• pp.122-131
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• 1999

This study examined the relationship between the sediment pollution and the occurrence of polychaetes in a heavily polluted saltwater lake, Lake Shihwa on the west coast of Korea, separated from the sea by a dike in 1994. The species composition of polychaete assemblage was compared with that found off the lake in Kyeonggi Bay. Environmental variables investigated both in and off the lake were the grain size distribution, chemical oxygen demand(COD) and metal concentrations (Al, Fe, Mn, V, Co, As, Pb, Cr and Cu) in the sediment. We sampled sediments at 10 stations in the lake and 25 stations in Kyeonggi Bay using a modified van Veen grab. The levels of COD, chromium, and copper in sediments were much higher in Lake Shihwa than in Kyeonggi Bay. Differences in the species composition were found along the pollution gradient. An azoic zone was observed in the most heavily polluted area at the upper reach of the lake and the Polydora ligni zone in the center of the lake. Bottom fauna were diverse in Kyeonggi Bay; however, Heteromastus filiformis predominated in the organically enriched sediment. The density of dominant species differed along the pollution gradient. The highest density or H. filiformis was round at the COD level or around 5.8 mg/g. The COD level in the sediment where P. ligni predominated was tow-fold higher than that where H. filiformis occurred in large numbers. The chromium and copper contents at which P. ligni showed a maximum abundance were 120 mg/kg and 127 mg/kg, respectively. The density of H. filiformis was highest at concentrations of 56 mg/kg chromium and 13 mg/kg copper.