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721.
In this study, bioaccumulation of the heavy metals (Fe, Zn, Cd) in the liver, gill, gonad and muscle tissues of Dicentrarchus labrax, Mugil cephalus and Sparus aurata were investigated seasonally. Camlik is the important fisheries lagoon located in The Iskenderun Bay, Mediterranean coast of Turkey. Due to heavy industrial and agricultural activities in the region, the bay has the polluted coastal waters of Turkey. Therefore, the levels of cadmium, zinc, iron were determined in the muscle in each species because of its importance for human consumption and also the liver, gill, gonad were analysed since these organs tend to accumulate metals. Heavy metal levels were found generally higher in the liver and gill than the gonad and muscle tissues in three species; the levels of all metals in a given tissue were generally higher in Mugil cephalus than the other two species. Data collected in this study suggest that Camlik lagoon is affected by a relatively metal pollution. The concentrations of Zn concentrations in the muscle tissues exceeded the acceptable levels for a food source for human consumption and other metals in the edible parts of the investigated fish were in the permissible safety levels for human uses.  相似文献   
722.
广东沿海风暴潮灾害应急管理初探   总被引:1,自引:1,他引:0  
广东沿海由于特殊的地理位置和气候条件,是风暴潮灾害的高发区。在分析广东沿海风暴潮灾害特点、广东省风暴潮灾害防御体系建设现状的基础上,总结了广东沿海风暴潮灾害应急管理中存在的问题,并提出了相应的对策和建议,可供工程技术人员和政府管理人员参考。  相似文献   
723.
The morphological form of mixed sand and gravel beaches is distinct, and the process/response system and complex dynamics of these beaches are not well understood. Process response models developed for pure sand or gravel beaches cannot be directly applied to these beaches. The Canterbury Bight coastline is apparently abundantly supplied with sediments from large rivers and coastal alluvial cliffs, but a large part of this coastline is experiencing long-term erosion. Sediment budget models provide little evidence to suggest sediments are stored within this system. Current sediment budget models inadequately quantify and account for the processes responsible for the patterns of erosion and accretion of this coastline. We outline a new method to extrapolate from laboratory experiments to the field using a geographical information system approach to model sediment reduction susceptibility for the Canterbury Bight. Sediment samples from ten representative sites were tumbled in a concrete mixer for an equivalent distance of 40 km. From the textural mixture and weight loss over 40 km tumbling, we applied regression techniques to generate a predictive equation for Sediment Reduction Susceptibility (SRS). We used Inverse Distance Weighting (IDW) to extrapolate the results from fifty-five sites with data on textural sediment composition to field locations with no data along the Canterbury Bight, creating a continuous sediment reductions susceptibility surface. Isolines of regular SRS intervals were then derived from the continuous surface to create a contour map of sediment reductions susceptibility for the Canterbury Bight. Results highlighted the variability in SRS along this coastline.  相似文献   
724.
ABSTRACT: This project analyzes suspended sediment flux through the upper Barataria basin in Louisiana during the winter season defined from November through April. The Barataria is a shallow coastal estuary located in southeastern Louisiana. The controls exerted by environmental parameters (such as wind or atmospheric pressure) in wetlands‐shallow bay ecosystems on transport of water and sediment were examined. Water samples were taken at a bayou (which serve as the inlet for flow to the estuary) on a regular basis. These samples were analyzed for total suspended solids and volatile suspended solids. Velocity, depth, temperature, salinity, conductivity, and meteorological measurements were all recorded at the time of each sampling. A multi‐parameter field probe was employed to continually monitor turbidity, water level, conductivity, and temperature during frontal events. These data were used in a regression analysis to examine the factors that drive carbon flux in the region. Investigations have determined that synoptic climate and prevailing weather conditions explain much of the variations in water levels, flow circulation patterns, salinity, and suspended sediment. Relatively small amounts of sediment appear to leave the estuary during normal tidal activity, but winter storm fronts result in significant fluxes of sediment in both up‐basin and down‐basin directions.  相似文献   
725.
通过借鉴国外发展可再生能源的经验,分析了我国能源供需分布格局及其区际能源平衡的特点,论证了实施可再生能源配额制在东部沿海地区能源结构优化过程中的意义及其途径。研究表明:①2010年,全国狭义可再生能源配额目标为5.1%,广义可再生能源配额目标为18.4%;②在东部沿海各省份均实现了广义配额目标的前提下,东部沿海地区可再生能源发电占其电力需求总量和能源消费总量的比重分别上升到18.4%和3.05%,能源结构得到优化;③为此,西部水电开发可达到全国总量的63.8%,小水电发电量可占全国总量的90.6%,实现西部优势再生能源的优先开发。  相似文献   
726.
727.
2009年江苏省沿海开发规划上升为国家战略,了解江苏沿海城市过去土地利用变化轨迹以及驱动因子是未来江苏省沿海城市土地利用规划的重要基础性工作。基于5期TM30 m×30 m RS遥感影像和GIS技术,分析东台市1980~2010年土地利用结构与变化轨迹,并通过典型对应分析(CCA)分析其与环境因子之间的关系。结果表明,东台市1980~2010年主要土地利用类型为耕地(2029.02 km2)、建设用地(155.31 km2)、草地(60.41 km2)和水域(56.56 km2)。近30年土地利用变化量占总面积的16.98%,其中耕地、草地和建设用地变化量最大。土地利用变化最主要轨迹为耕地转建设用地,主要位于市区及周边地区,其次为草地转耕地,主要位于海岸带地区。东台市土地利用变化热点区域分别为市中心和海岸带,二者相距较远,相对独立。CCA分析显示城镇、交通和斑块形状复杂程度等是影响沿海城市土地利用变化的重要因子,海岸线作为沿海城市主要特征,随着海岸滩涂围垦开发,到海岸距离也是沿海城市土地利用变化的重要影响因子。因此,在沿海城市土地利用规划中需要重点考虑城镇布局、交通等基础设施分布、斑块的形状等因子,通过海岸带土地利用方式转变来加强市区与海岸带之间联系,促进社会经济转变,进一步保护海岸生态环境,提高海岸开发综合效益,引导土地利用走向可持续发展道路。  相似文献   
728.
《Environmental Hazards》2013,12(3):233-248
Coastal hazard management involves the assessment of vulnerability in natural and human environments. Indices incorporating a diversity of indicators have therefore been used extensively to provide spatial analyses of the degree of vulnerability. Such indices are typically applied at global and national scales, and they involve varying degrees of simplification and aggregation of information. The degree of simplification that is desirable depends on the management scale, and higher resolution is required at the local compared to the global scale. To investigate the implications of spatial scale in depicting coastal hazard risk, coastal vulnerability indices were developed at national (Northern Ireland), local authority and site levels. Variables were separated into three sub-indices: a coastal characteristics sub-index concerned with the resilience and susceptibility of the coast to erosion, a coastal forcing sub-index to characterize the forcing variables contributing to wave-induced erosion and a socio-economic sub-index to assess the infrastructure potentially at risk. The three sub-indices were merged to calculate the overall index, which is portrayed in the form of colour-coded vulnerability maps. While a common tripartite index could be employed at national, regional and local scales, the nature of the data used to quantify many of the variables varies according to the scale of management. Some important local variations in vulnerability are masked by simplifications at the national scale. For some variables more detailed information is available as the spatial resolution of the study increases, while others become obsolete as data are of insufficient resolution to differentiate real variability at more detailed scales. The results highlight the importance of spatial scale in developing indices of vulnerability: while a common index architecture can be applied, the selection of variables must take account of the scale at which the hazard is to be assessed. It is likely that limits on index development will also be imposed by data availability at various scales.  相似文献   
729.
With the aim of using Mytilus galloprovincialis acetylcholinesterase (AChE) and glutathione S-transferases (GST) activities as biomarkers of environmental contamination in risk assessment studies along the northwest Portuguese coast, the objective of this study was to provide background information related to: (1) baseline values of these enzymatic activities both in reference and contaminated areas and their responsiveness as indicators of exposure to environmental contaminants; (2) the importance of seasonal variations of such biomarkers in M. galloprovincialis along this area. For this, the activity of these enzymes was seasonally determined in mussels collected from four sites, including a reference and three stations with different contamination sources along the referred area. Statistically significant differences on both enzymatic activities were found among the four sampling stations, at the four sampling periods. In comparison to the reference station, lower AChE and higher GST activity values were found in mussels collected in stations potentially contaminated by pesticides and domestic/industrial effluents and in mussels collected in the vicinity of an oil refinery and an industrial/mercantile harbour, respectively. The results obtained in this work highlighted the potential suitability of these biomarkers to be used as components of environmental monitoring programs in risk assessment studies along the northwest Portuguese coast. Since a seasonal variation in both enzymatic activities was found, the possible implications of such variability in the use of these enzymes as environmental biomarkers are also discussed.  相似文献   
730.
The distribution of fly ash that is discharged in the form of slurry from a power plant situated on the southern coast of the Black Sea was simulated with a transport model that used the velocity fields produced by isopycnic modelling. It is shown that a significant amount of ash is deposited in the vicinity of the discharge location. The ash remaining in the water column settles in a manner dependent on the direction and intensity of the local current regime. Generally, summer and spring are found to be seasons when the circulation is weak and the ash dispersion is confined to the shore. The model results are conditional upon obtaining observational data for validation.  相似文献   
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