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Evaluation for the ecological quality status of coastal waters in East China Sea using fuzzy integrated assessment method
2012
Wu, H.Y. | Chen, K.L. | Chen, Z.H. | Chen, Q.H. | Qiu, Y.P. | Wu, J.C. | Zhang, J.F.
This research presented an evaluation for the ecological quality status (EcoQS) of three semi-enclosed coastal areas using fuzzy integrated assessment method (FIAM). With this method, the hierarchy structure was clarified by an index system of 11 indicators selected from biotic elements and physicochemical elements, and the weight vector of index system was calculated with Delphi-Analytic Hierarchy Process (AHP) procedure. Then, the FIAM was used to achieve an EcoQS assessment. As a result of assessment, most of the sampling stations demonstrated a clear gradient in EcoQS, ranging from high to poor status. Among the four statuses, high and good, owning a ratio of 55.9% and 26.5%, respectively, were two dominant statuses for three bays, especially for Sansha Bay and Luoyuan Bay. The assessment results were found consistent with the pressure information and parameters obtained at most stations. In addition, the sources of uncertainty in classification of EcoQS were also discussed.
显示更多 [+] 显示较少 [-]Monitoring temporal and spatial trends of legacy and emerging contaminants in marine environment: Results from the environmental specimen bank (es-BANK) of Ehime University, Japan
2012
Tanabe, Shinsuke | Ramu, Karri
The Environmental Specimen Bank (es-BANK) for Global Monitoring at the Center for Marine Environmental Studies, Ehime University, Japan has more than four decades of practical experience in specimen banking. Over the years, es-BANK has archived specimens representing a wide range of environmental matrices, i.e. fishes, reptiles, birds, aquatic mammals, terrestrial mammals, human, soils, and sediments. The samples have been collected as part of the various monitoring programs conducted worldwide. The current review is a summary of selected studies conducted at the Center for Marine Environmental Studies, on temporal and spatial trends of legacy and emerging contaminants in the marine environment. One of the major conclusions drawn from the studies is that environmental problems are no more regional issues and, thus, environmental specimen banking should not be limited to national boundaries, but should have a global outlook.
显示更多 [+] 显示较少 [-]Coastal resource degradation in the tropics: Does the tragedy of the commons apply for coral reefs, mangrove forests and seagrass beds
2012
Wilkinson, Clive | Salvat, Bernard
The keynote paper by Garrett Hardin 44years ago introduced the term ‘tragedy of the commons’ into our language (Hardin, 1968); this term is now used widely, but it is neither universally accepted nor fully understood. Irrespective, the ‘tragedy of the commons’ is an increasing reality for more than 500 million people that rely on the biodiversity resources and services of tropical coral reefs, mangrove forests, seagrass beds and associated fisheries. These natural resources continue to decline despite major advances in our scientific understanding of how ecosystems and human populations interact, and the application of considerable conservation and management efforts at scales from local user communities to oceans. Greater effort will be required to avert increasing damage from over-exploitation, pollution and global climate change; all deriving from increasing exploitation driven by poverty and progress i.e. continuing to expand development indefinitely and extraction of resources at industrial scales. However, the ‘tragedy’ concept has been widely criticized as a simple metaphor for a much larger set of problems and solutions. We argue that the ‘tragedy’ is essentially real and will continue to threaten the lives of millions of people unless there are some major moral and policy shifts to reverse increasing damage to coastal habitats and resources. We agree with the conclusion by Hardin that the solution to the tragedy will not be through the application of natural sciences, but via implementing exceedingly difficult and controversial moral decisions. An extreme example of a moral and controversial direction suggested by Hardin was in re-examining the ‘freedom to breed’ as an inherent human value. The need for ‘moral decisions’ is even greater in 2012.
显示更多 [+] 显示较少 [-]Effects of nitrate on nitrite toxicity to Microcystis aeruginosa
2012
Chen, Weimin | Tong, Haibin | Liu, Hao
The aim of this study was to investigate the effect of nitrate on nitrite toxicity to Microcystis aeruginosa. Short-term uptake experiment revealed nitrate could depress the nitrite active uptake. The long-term experiment of nitrate effects on nitrite toxicity showed a negative relationship between the growth and intracellular nitrite levels of M. aeruginosa. The net nitrite uptake displayed a decline in the range of 0–150mg NO₃ ⁻-NL⁻¹ and an elevation at 200mg NO₃ ⁻-NL⁻¹, whereas the activities of nitrate reductase (NR) were more sensitive to nitrate than nitrite reductase (NiR). As a result, the total intracellular nitrite levels tended to decrease up to 100mg NO₃ ⁻-NL⁻¹ then increased at 150–200mg NO₃ ⁻-NL⁻¹. These results suggested the existence of external nitrate could affect the toxicity of nitrite to alga through changing intracellular nitrite content.
显示更多 [+] 显示较少 [-]Macrobenthic community structure in the northern Saudi waters of the Gulf, 14years after the 1991 oil spill
2012
Joydas, T.V. | Qurban, Mohammad A. | Al-Suwailem, Abdulaziz | Krishnakumar, P.K. | Nazeer, Zahid | Cali, N.A.
The 1991 Gulf oil spill heavily impacted the coastal areas of the Saudi waters of the Arabian Gulf and recent studies have indicated that even 15years after the incident, macrobenthos had not completely recovered in the sheltered bays in the affected region such as, Manifa Bay. This study investigates the community conditions of macrobenthos in the open waters in one of the impacted areas, Al-Khafji waters, about 14years after the spill. Diversity measures and community structure analyses indicate a healthy status of polychaete communities. The BOPA index reveals that oil sensitive amphipods were recolonized in the study area. This confirms that the benthic communities of the oil spill impacted area had taken only <14 years to recover in the open waters of the impacted areas. The study also reveals the existence of three distinct polychaete communities along the depth and sediment gradients.
显示更多 [+] 显示较少 [-]Aspects of the digestive gland cells of the mussel Mytilus galloprovincialis, in relation to lysosomal enzymes, lipofuscin presence and shell size: Contribution in the assessment of marine pollution biomarkers
2012
Raftopoulou, E.K. | Dimitriadis, V.K.
The present study investigates the histochemical localization of N-acetyl-β-hexozaminidase (Hex), acid phosphatase (AcP) and β-glucuronidase (β-Gus) in the digestive gland of mussels Mytilus galloprovincialis, as well as the clarification of suitable enzyme for biomarkers’ application dealing with lysosomes. The results show more intense and homogenous localization of Hex, in relation to AcP and β-Gus and, thus, Hex histochemistry is supported as more suitable procedure for the evaluation of “lysosomal membrane stability” and “morphometrical alterations of lysosomes”. The affection of lipofuscin granules on lysosomal enzymes’ activity is also discussed. Additionally, the present study examines the response of small- and large-sized mussels M. galloprovincialis by assessing the “lysosomal membrane stability”, “morphometrical alterations of lysosomes”, “lysosomal response index (LRI)” and “structural epithelial changes in digestive tubules”. The results indicate appreciable alterations of the above parameters in large-sized mussels, supporting their greater influence by the environmental factors, in relation to small-sized ones.
显示更多 [+] 显示较少 [-]A comparison of integrated and discrete depth sampling for monitoring toxic species of Dinophysis
2012
Escalera, Laura | Pazos, Yolanda | Dolores Doval, María | Reguera, Beatriz
Dinophysis acuminata and Dinophysis acuta produce lipophilic toxins that cause most shellfish harvesting closures in the Atlantic coastal waters of Europe. Dinophysis often exhibit patchy distributions and sampling with conventional methods may fail to detect them. A 6-month calibration study in 2006, plus an additional sampling in 2010 were carried out in Galicia to compare Dinophysis counts obtained from weekly high vertical resolution bottle samples with depth-integrated hose samples. Counts with these two methods were comparable at some depth-ranges, but hose maxima were over one order of magnitude lower under thin-layer scenarios. Estimates from hose samplers should be used with caution in programmes using a “Dinophysis index”, either to trigger shellfish sampling or to establish precautionary harvesting closures. In general, hose samplers provide reliable information on the occurrence of Dinophysis except under extreme site-specific hydrodynamic conditions. This study adds new information about the heterogeneous, specific vertical distributions of two Dinophysis spp.
显示更多 [+] 显示较少 [-]Comparison of granulometric methods and sampling strategies used in marine habitat classification and Ecological Status assessment
2012
Forde, James | Collins, Patrick Colman | Patterson, Adrian | Kennedy, Robert
Sediment particle size analysis (PSA) is routinely used to support benthic macrofaunal community distribution data in habitat mapping and Ecological Status (ES) assessment. No optimal PSA Method to explain variability in multivariate macrofaunal distribution has been identified nor have the effects of changing sampling strategy been examined. Here, we use benthic macrofaunal and PSA grabs from two embayments in the south of Ireland. Four frequently used PSA Methods and two common sampling strategies are applied. A combination of laser particle sizing and wet/dry sieving without peroxide pre-treatment to remove organics was identified as the optimal Method for explaining macrofaunal distributions. ES classifications and EUNIS sediment classification were robust to changes in PSA Method. Fauna and PSA samples returned from the same grab sample significantly decreased macrofaunal variance explained by PSA and caused ES to be classified as lower. Employing the optimal PSA Method and sampling strategy will improve benthic monitoring.
显示更多 [+] 显示较少 [-]Role of living environments in the accumulation characteristics of heavy metals in fishes and crabs in the Yangtze River Estuary, China
2012
Zhao, Shou | Feng, Chenghong | Quan, Weimin | Chen, Xiaofeng | Niu, Junfeng | Shen, Zhenyao
Correlation of heavy metals in the tissues of typical organisms (i.e., fishes and crabs) and those in their living environments (i.e., surface water, bottom water, and sediment) in Yangtze River Estuary has been qualitatively and quantitatively analyzed. Metal levels followed the trend: sediments >Eriocheir sinensis>Eriocheir leptognathus>benthic fish>pelagic fish>bottom water>surface water. Tissues in fishes and crabs of different species and sizes had diverse metal bioaccumulation characteristics, which was significantly affected by environment factors and their living habits. Metal levels in legs of crabs, and heads and skins of fishes showed significant correlations with those in their living environments. Collichthys lucidus is an effective bioindicator for assessing metal levels in water. No significant health risk was identified by the estimated daily intake and target hazard quotients analyses.
显示更多 [+] 显示较少 [-]Genotoxicity and development effects of brominated flame retardant PBDEs and UV-exposed PBDEs on grass shrimp (Palaemonetes pugio) embryo
2012
Lee, Hyo Jin | Kim, Gi Beum | Lee, Richard F.
To understand how polybrominated diphenyl ethers (PBDEs) affect the hatching sensitivity of grass shrimp embryos in different developmental stages, the hatching rates of embryos were measured after PBDE exposure on the early- and late-stage embryo of grass shrimp. PBDEs had no clear influence on the hatching rate. Also, to investigate on the reproductive and genetic toxicities of UV-exposed PBDEs, the hatching rate and DNA damage of stage 7 embryos were also measured. PBDEs had no significant impact on the hatching rate and DNA damage of grass shrimp in most experimental conditions regardless of embryo developmental stage or UV exposure, but in the case of UV-exposed BDE-47, the hatching rate was decreased, suggesting a potential reproductive toxicity. This research is meaningful because it is the first study to propose that PBDEs can cause reproductive toxicity in marine organism, after flowing into the ocean and undergoing photochemical reactions stimulated by UV.
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