Heavy metal accumulation in estuarine sediments in a historical mining of Cornwall     

W.W.-S. Yim 《Marine pollution bulletin》1976,7(8):147-150

Sediments in the Hayle estuary in a historical mining area of Cornwall have been found to contain exceptionally high concentrations of tin, arsenic, copper, lead, tungsten and zinc. In this study, the distribution of these heavy metals is correlated with pollution from past mining activity through mine waste discharge into streams, and changes which took place at the time of the development of the Upton Towans.  相似文献   

香港西博寮海峡WB7孔的第四纪沉积及硅藻研究   总被引：1，自引：1，他引：1  

李家英  严维枢 《地质论评》1997,43(6):616-630

香港西搏寮海峡ＷＢ７孔第四纪沉积物中共有硅藻５４属，１８６个分类单位，该硅藻生物群以沿岸潮间带和近岸浅海种为主，伴有热性，暖热性浮游硅藻。依据硅藻在剖面中的分布特征，丰度及百分比含量变化，自下而上可划分出６个硅藻组合带。并明显反映该沉积时期的古气候与古环境特征，其中第５，６，带相当于全新世，其余４个带均属更新世。  相似文献   

Biomarkers in marbled flounder (Pleuronectes yokohamae) from contaminated and reference sites in South Korea     

Jee Hyun Jung  R.F. Addison  Un Hyuk Yim  Sang Hee Hong  Sungyong Ha  Won Joon Shim   《Marine pollution bulletin》2009,58(11):1754-1759

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ARD generation and corrosion potential of exposed roadside rockmass at Boeun and Mujoo,South Korea     

Sang Woo Ji  Young Wook Cheong  Gil Jae Yim  Jayanta Bhattacharya 《Environmental Geology》2007,52(6):1033-1043

Acid rock drainage (ARD) is a longstanding problem often associated with the resulting corrosion due to the acidity generated from sulfidic oxidation. To evaluate characteristics of ARD and corrosion, samples from the road side rock mass of Boeun and Mujoo were analysed using X-ray diffraction, acid/base accounting and Leaching tests. The results indicated that many samples had a pyritic origin and can be regarded as acid-generating rocks. The Leaching test showed that the average pH of the leachates of samples from both Boeun and Mujoo were moderately acidic, ranging from 3 to 4. Interestingly, as acidity increases from pH 4, the SO₄₋, Fe, Al and Mg concentrations increase abnormally. Samples from roadside slope of Mujoo showed high corrosive potential. Maximum sulfide oxidation rate of a sample taken from Mujoo was as high as 5,166 mg/kg/week.  相似文献   

A preliminary report of persistent organochlorine pollutants in the Yellow Sea   总被引：5，自引：0，他引：5  

Oh JR  Choi HK  Hong SH  Yim UH  Shim WJ  Kannan N 《Marine pollution bulletin》2005,50(2):217-222

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Large angular motions of tethered surface buoys     

J. W. Leonard  K. Idris  S. C. S. Yim 《Ocean Engineering》2000,27(12):290

A three-dimensional coupled analysis of the interaction of a floating buoy and its mooring is studied. External loads include hydrodynamic forces, tether tensions, wind loads and system weight and buoyancy. Nonlinearities include large rotational and translational motions and non-conservative fluid loads. The mooring problem is formulated as a nonlinear two-point-boundary-value-problem. At each instant in time, the mooring problem is solved by direct integration using a successive iterative algorithm to satisfy boundary conditions. Buoy kinetic and kinematic equations are derived assuming large angles represented by Euler parameters. Coupling between the buoy and the mooring is enforced by matching the velocities of the tether and buoy at the attachment point. A predictor-corrector coupling algorithm is used with multiple sizes of time steps used to provide stability for the separate mooring and buoy models. Numerical results are compared to experimental responses of three types of buoys (sphere, spar and disc) subject to both regular and irregular waves.  相似文献   

Assessment of pollution and ecological risk of heavy metals in the surface sediments of Ulsan Bay,Korea     

Kongtae Ra  Joung-Keun Kim  Sang Hee Hong  Un Hyuk Yim  Won Joon Shim  Seung-Yong Lee  Young-Ok Kim  Jaesoo Lim  Eun-Soo Kim  Kyung-Tae Kim 《Ocean Science Journal》2014,49(3):279-289

Heavy metal concentrations in the surface sediments of specially managed Ulsan Bay were investigated to determine metal distribution, pollution status and its ecological risk using pollution indices (enrichment factor and geo-accumulation index), potential ecological risk index and sediment quality guidelines (SQGs). The order of mean concentration (mg/kg) of metals was Zn (361.9) > Cu (95.6) > Pb (90.7) > Cr (64.7) > Ni (32.2) > Co (16.6) > As (15.8) > Cd (0.40) > Hg (0.16) in sediments of Ulsan Bay. Spatial distribution of metals in sediments showed a significantly higher concentration near industrial complexes, indicating that metal pollution is caused by anthropogenic sources. The results of enrichment factor (EF) and geo-accumulation index (I_geo) showed that sediments were significantly accumulated with Cu, Zn, As, Cd, Pb and Hg, indicating moderate to very severe enrichment (pollution) by these metals. Based on the potential ecological risk index, Hg and Cd posed a very high and a considerable potential ecological risk. Cu and As posed a moderate potential ecological risk, while, other metals (Cr, Co, Ni, Zn and Pb) rarely posed any potential ecological risk to the coastal environments. The sediments in Ulsan Bay showed a very high level of ecological risk, dominated by Hg and Cd. Metal concentrations in sediments were 80% for Cu, 96.7% for Zn, 50% for As, 70% for Pb and 50% for Hg above the threshold effects level (TEL), respectively.  相似文献   

Biomarker responses in pelagic and benthic fish over 1 year following the Hebei Spirit oil spill (Taean, Korea)   总被引：1，自引：0，他引：1  

Jung JH  Kim M  Yim UH  Ha SY  An JG  Won JH  Han GM  Kim NS  Addison RF  Shim WJ 《Marine pollution bulletin》2011,62(8):1859-1866

After the Hebei Spirit oil spill incident (7th December, 2007) in the west coast of Korea, contamination of biliary PAH metabolite and hepatic biomarkers in a pelagic and a benthic fish was monitored for 1 year. Concentrations of 16 PAHs and alkylated PAHs in fish muscle were highest (22.0 ng/g d.w. for 16 PAHs and 284 ng/g d.w. for alkylated PAHs) at 5 days after the spill and then decreased rapidly to background levels at 11 months after the spill. Fish from the oiled site had elevated biliary PAH metabolite concentrations immediately after the spill; these declined steadily in both species, but were still above reference site concentrations 2 months after the spill. Oiled-site fish showed hepatic CYP 1A induction whose trend closely followed those of biliary PAH metabolite concentrations, implying continuous exposure to PAHs. Brain acetylcholinesterase activity was not related to oil exposure.  相似文献   

Polychlorinated biphenyls (PCBs) in a benthic ecosystem in Gwangyang Bay, South Korea     

Hong SH  Kannan N  Yim UH  Choi JW  Shim WJ 《Marine pollution bulletin》2011,62(12):2863-2868

Benthic ecosystem in Gwangyang Bay, a fast developing industrial area with steel production, port container handling, petroleum and other chemical processing in South Korea was studied. The average levels of polychlorinated biphenyls (ΣPCB) in the benthic components were: seawater 2.99 ± 0.13 (ng/L); sediment 294 ± 118 (ng/g TOC); [biota=ng/g lipid] starfish 92; prawn 131 ± 2; mussels 127 ± 22; crab 182 ± 114; clam 187; polychaeta 215; sea cucumber 497 ± 90; squill 603 ± 38; fish 396 ± 159. Levels in the inner bay samples were higher than the outer bay samples suggesting land based pollution. Good correlation (r(2)=0.79; p<0.05) existed between PCB concentration and lipid content indicating partitioning processes in action. PCB signature in the abiotic and biotic components shows enrichment of lower chlorinated congeners emitted by a unique source nearby, viz. steel manufacturing plant.  相似文献   

Burial of organic carbon in Holocene sediments of the Zhujiang (Pearl River) and Changjiang (Yangtze River) estuaries   总被引：1，自引：0，他引：1  

Shouye Yang  Min Tang  Wyss W.-S. Yim  Yongqiang Zong  Guangqing Huang  Adam D. Switzer  Yoshiki Saito 《Marine Chemistry》2011,123(1-4):1-10

The East Asian marginal seas are important sinks of terrigenous materials transported by large rivers. In this study two cores from the Changjiang (Yangtze River) and Zhujiang (Pearl River) estuaries and one core from the inner shelf off of Hong Kong were investigated to examine the burial of organic matter during the postglacial period and its possible links with paleoenvironmental changes. Based on a simple two end-member mixing model, the terrestrial organic matter supplied primarily from the Zhujiang and Changjiang dominates the estuarine areas while marine organic matter contributes more to the inner-mid shelf. The competing contributions of terrestrial and marine organic matter are responsible for the downcore variations of organic elemental compositions. The overall decreasing shifts of total organic carbon concentrations and total organic carbon to total nitrogen ratios in the Zhujiang estuarine sediments since 6.5 kaBP seems to support the notion that depth profiles of organic matter compositions deposited in the Zhujiang Estuary can aid in the reconstruction of monsoon history in the Holocene. Nevertheless, organic matter compositions in the Changjiang Estuary and inner shelf off of southeastern Hong Kong respond in a different and more complex way to freshwater discharges or precipitation changes (monsoon variability) in the catchments, owing to complex controls of deposition and preservation of organic matter in these estuarine and shelf environments. Caution is therefore needed in using organic elemental and isotopic compositions to decipher paleoenvironmental changes in East Asian continental shelves where intense river–sea interactions occur and sedimentary environments change drastically.  相似文献