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1.
山东半岛近岸海域生态系统健康综合评价   总被引:3,自引:0,他引:3  
为了构建基于多指标体系的生态系统健康评价方法,作者在调研了大量国内外文献的基础上,通过实证研究和量化分析,对山东半岛近岸海域生态系统健康的现状做出了较为客观的评价。在综合考虑影响海洋生态系统健康的各种因素的基础上,构建了山东半岛近岸海域生态系统健康评价指标体系,从陆源压力、水质状态和生物响应3个方面对山东半岛近岸海域生态系统健康和环境压力进行分析。结果显示:2006年山东半岛近岸海域生态健康状况基本呈现由外海到近岸逐渐变差的态势,其中生态健康状况较差的海域主要集中在莱州湾西南部、烟台北部海域、威海的沿岸海域以及山东半岛东南部海域。  相似文献   

2.
The present study evaluates the potential of Hymeniacidon heliophila as bioindicator of PAH contamination. For this, concentration of 33 PAH was determined in organisms from sites with different contamination level including the heavily polluted Guanabara Bay, Rio de Janeiro, and less impacted coastal areas. PAH concentration and typology were determined in sponges collected from different depths and in two different seasons. The brown mussel broadly studied as bioindicator was also sampled from the same sites for comparison. Both species provided similar information on total PAH concentration which is related to site contamination level. Sponges, however, revealed slight tendency to accumulation of combustion-derived PAH in relation to petrogenic compounds. Differences in PAH typology between species may derive from the interspecific variation in particle size ingestion. Different hydrocarbon typologies were observed in sponges from dry and wet season and PAH concentration varied with depth. H. heliophila may be used as an alternative approach to investigate the presence and sources of PAH in estuarine areas.  相似文献   

3.
This study examined seasonal and annual occurrences of warm oceanic tintinnid species in southern Korea coastal waters. The indicative species of tintinnids was monitored using three approaches: monitoring from cruises traveling from the warm pool in the western North Pacific to the Korea Strait; biweekly or monthly monitoring in the Korea Strait; and daily monitoring in the nearshore water. Annual pulses of warm oceanic indicator species were regularly observed in the Korea Strait. In September 2008 recorded a maximum species number of warm water indicators, a representative species for warm oceanic waters, Climacocylis scalaroides was simultaneously detected in the nearshore water as well as the Korea Strait. The result indicates that the greater warm water extension into Korean coastal areas was in September 2008. Sharp declines in species diversity were observed in the transitional area between neritic and Kuroshio zone in East China Sea (ECS). Epiplocyloides reticulata, reported previously as a Kuroshio indicator, was considered an ECS indicator species, as it was undetected in the western North Pacific central zone but was found abundantly in the ECS. Tintinnid species can be used as biological indicators to detect the inflow of warm oceanic waters into Korean coastal waters.  相似文献   

4.
There were climatic regime shifts over the North Pacific in 1976 and 1988 which affected the dynamics of the marine ecosystem and fisheries resources in Korean waters. Precipitation in Korean waters showed a decadal scale climatic jump, especially of Ullungdo Island, reflecting the regime shift that occurred in the North Pacific. The variation was also detected in East Asian atmospheric systems. The Aleutian Low and North Pacific High Pressure Systems showed substantial changes in 1976 and around 1987–89. 1976 was an unusually warm year for Korea; mean sea surface temperature (SST) was higher than ‘normal’ and was accompanied by a northward shift in the thermal front. Post 1976, the volume transport of the Kuroshio Current increased and higher seawater and air temperatures persisted until 1988. Other shifts occurred after 1976 such as an increase in mixed layer depth (MLD) and biological changes in the ecosystem of Korean waters including decreases in spring primary production and an increase in autumn primary production. Primary production increased again after 1988, and was followed by a significant increase in zooplankton biomass after 1991. The 1976 regime shift was manifested by a decreased biomass and production of saury, but an increase in biomass and production of sardine and filefish in Korean waters. After 1988, recruitment, biomass, and production of sardine collapsed while those of mackerel substantially increased. Based on these observations, hypotheses on the relationship between the climate-driven oceanic changes and changes in fisheries resources were developed and are discussed.  相似文献   

5.
Both water and suspended particulate matter in the deep water of the Gulf of St. Lawrence are greatly enriched in manganese. Maximum dissolved manganese concentrations are encountered close to the sediment-water interface whereas the particulate matter with highest manganese content occurs 30–100 m above the bottom. The elevated concentrations are attributed to the diagenetic release of dissolved manganese from the underlying fine-grained sediments and its subsequent precipitation in the water column. The rate of manganese precipitation is rapid compared to the rates of diffusion and mixing in the bottom water. Part of the manganese-enriched particulate matter becomes mixed throughout the water column by advection and diffusion. Thus, particles enriched in manganese can ultimately be carried into the open ocean by prevailing currents. This process, which appears to be widespread in eastern Canadian coastal waters, enables manganese originally associated with rapidly settling terrigenous particles to be transferred to slowly settling fine-grained suspended particles entering the ocean from coastal environments. In this way, riverborne manganese of terrigenous origin may well account for a major proportion of the excess manganese in pelagic sediments.  相似文献   

6.
7.
《Coastal Engineering》2005,52(8):673-689
Formulae for bedload transport of sediments in conditions characteristic of coastal waters are developed from principles of physics. They cover driving forces of: current alone, current plus symmetrical waves, current plus asymmetrical waves, asymmetrical waves alone, and integrated longshore transport. In each case the transport is given as one or more analytical functions of the basic input variables. The formulae are tested against laboratory and field data, and give predictions that lie within a factor of 2 of the measured values for between 47% and 91% of the data, depending on the driving force. The formulae are suited to practical application in coastal waters, especially for transport of coarse materials such as shingle, and also for the bedload component of transport of sand.  相似文献   

8.
By reviewing the history of fishery exploitation in the coastal waters of west Canada and east Korea, related with contrasting life history strategies of the dominant species, the fishery management challenges that each country would face in the upcoming decades were outlined. In the ecosystem of the Canadian western coastal waters, the dominant oceanographic feature is the coastal upwelling domain off the west coast of Vancouver Island, the northernmost extent of the California Current System in the eastern North Pacific. In the marine ecosystem of the eastern coasts of Korea (the Japan/East Sea), a major oceanographic feature is the Tsushima Warm Current, a branch of the Kuroshio Current in the western North Pacific. Fishes in the Canadian ecosystem are dominated by demersal, long-lived species such as flatfish, rockfish, sablefish, and halibut. During summer, migratory pelagic species such as Pacific hake, Pacific salmon, and recently Pacific sardine, move into this area to feed. In the late 1970s, Canada declared jurisdiction for 200 miles from their coastline, and major fisheries species in Canadian waters have been managed with a quota system. The overall fishing intensity off the west coast of Vancouver Island has been relatively moderate compared to Korean waters. Fishes in the ecosystem of the eastern Korean waters are dominated by short-lived pelagic and demersal fish. Historically, Korea has shared marine resources in this area with neighbouring countries, but stock assessments and quotas have only recently (since the late-1990s) been implemented for some major species. In the Korean ecosystem, fisheries can be described as intensive, and many stocks have been rated as overfished. The two ecosystems responded differently to climate impacts such as regime shifts under different exploitation histories. In the future, both countries will face the challenge of global warming and subsequent impacts on ecosystems, necessitating developing adaptive fisheries management plans. The challenges will be contrasting for the two countries: Canada will need to conserve fish populations, while Korea will need to focus on rebuilding depleted fish populations.  相似文献   

9.
Dissolved cadmium and copper concentrations have been determined in 76 surface water samples in coastal and ocean waters around Scotland by anodic stripping voltammetry (ASV). A trace metal/salinity ‘front’ is observed to the west, north and north-east of Scotland separating high salinity ocean water (>35 × 10−3) with low concentrations of dissolved Cd and Cu from lower salinity (<35 × 10−3) coastal water containing higher concentrations of Cd and Cu. Mean Cd concentrations in ocean and coastal waters are 7 ng dm−3 (0·06 n ) and 11 ng dm−3 (0·10 n ) respectively; for Cu the respective levels are 60 ng dm−3 (0·95 n ) and 170 ng dm−3 (2·68 n ). The observed distribution is attributed principally to freshwater runoff and the advection of contaminated Irish Sea water into the study area.  相似文献   

10.
连云港近岸海域沉积物运移趋势   总被引:2,自引:1,他引:2  
张存勇 《海洋学报》2013,35(3):172-178
基于连云港近岸海域夏冬季大面积多站表层沉积物样品的粒度分析结果,采用Gisedtrend粒径趋势分析方法,研究了沉积物的运移趋势,探讨了粒径趋势分析的影响因素,结果表明,连云港近岸海域沉积物运移趋势较显著,在海州湾海域沉积物运移趋势为西南向,表现为湾顶淤积;在港口南部海域沉积物运移趋势显示为汇聚区。特征距离、采样网格、周围环境和粒度组分影响粒径趋势的分析结果;综合考虑岸线、岛屿、人工边界等自然环境以及多源粒度组分能够提高粒径趋势分析结果的合理性。  相似文献   

11.
The uptake of a suite of 19 metals from coastal seawaters upon both glass and Teflon surfaces reflected primarily the sorption of particulate matter derived from crustal rock weathering. Uptake for all elements was greater in the light than in the dark. Based upon these and earlier results, a new definition of scavenging for environmental systems is proposed.  相似文献   

12.
The effects that man has on coastal waters are enumerated and what needs to be known to evaluate those effects is considered. Instruments and techniques are described for measuring and sampling the physical, chemical, and biological situation in the sea. Some suggestions are offered for improvement in the existing instrumentation. Also noted are certain limitations in present capabilities including the inability to satisfactorily determine the effects on the environment of fisheries, of oil spills, or of changes in ocean conditions.  相似文献   

13.
Because of the variable, unpredictable nature of many potential nutrient sources for coastal phytoplankton primary production needs in the north-western Gulf of Mexico, benthic regeneration was investigated as a more constant source of nutrients to this ecosystem. Water column ammonia profiles taken at several locations on the south Texas inner-shelf in the last seven years showed peak concentrations in bottom waters. Benthic chamber measurements verified the presence of ammonia fluxes at the mud-water interface in south Texas coastal waters. These fluxes were related to benthic faunal activity as measured by sediment metabolism. Laboratory experiments, designed to test the effect of benthic faunal removal on nutrient regeneration, suggested that the fauna play a role in regulating this process. How this regulation may occur is discussed. It was estimated that annual benthic regeneration rates can supply 69% of the nitrogen required to support phytoplankton primary production in these coastal waters.  相似文献   

14.
浙江省近岸海域底栖生物生态研究   总被引:5,自引:1,他引:5  
对2003年4~5月在浙江省近岸海域底栖生物调查中获得的126种底栖生物的种类组成、生物量及栖息密度的分布和群落结构进行了叙述和讨论。结果表明:底栖生物种类组成以甲壳动物及软体动物占优势,两者占生物总种数的51.6%;浙江近岸海域底栖生物总平均生物量为18.74 g/m2;总平均栖息密度为89.1个/m2。按生态特征划分,调查海域的底栖生物可分成7个群落。分析调查海域各测站群落结构指数可以看出,浙江近岸海域70%测站呈现出生物多样性指数低及种类分布不均匀等特点。  相似文献   

15.
The coastal ecosystem health assessment is a field of increasing importance. In this paper, a preliminary assessment of ecosystem health in Zhejiang coastal water zone was made, mainly based on remote sensing data and GIS technique. Its spatial and quantitative evaluation was facilitated by the progress of remote sensing and GIS technique development. Firstly, human activities, hydrology and ecosystem problems in the study area were discussed and analyzed. Secondly, from 4 aspects of human stress, physical, chemical and biological responses to anthropogenic activities and natural stress, several indicators such as water transparency (Secchi Disk Depth, SDD), suspended substance concentration, dissolved inorganic nitrogen, active phosphate, chlorophyll, harmful algae bloom, as well as distribution of sewage, sea lanes and port were employed. Thirdly, the Analytic Hierarchical Process was used for indicator weight calculation, and the ecosystem health criteria were established according to the integrative analysis of national water quality criteria, similar coastal ecosystem health research in other places or data inherent properties. The results indicated that from 2005 to 2007 the coastal water ecosystem health value in Zhejiang Province was unhealthy and needs ecological restoration by human intervention.  相似文献   

16.
Sensitivity analysis of a coastal marine ecosystem   总被引:1,自引:0,他引:1  
An ecosystem with four compartments, i.e. PO4-P, phytoplankton, zooplankton and detritus, in a coastal region was considered. Sensitivity analysis of a phosphorus flow model in well-mixed water without currents concludes that (1) the maximal photosynthetic rate,V m , in Michaelis-Menten relation plays an important role in the distribution of biomass among compartments but the half saturation constant,K s , is not so important, (2) the natural death rate of phytoplankton is important for the ecosystem, (3) the natural death rate of zooplankton is also effective on the ecosystem.A numerical experiment was also performed on the ecosystem with four compartments are also studied using a dynamical barotropic model of tidal currents of Mikawa Bay (Japan). Diffusion coefficient in diffusion equation plays the role of a linear smoothing parameter in the horizontal distribution of compartment. On the other hand, perturbations of biological parameters cause nonlinear variations in the horizontal distribution of compartment.  相似文献   

17.
中国近岸海域潜在性富营养化程度的评价   总被引:105,自引:6,他引:105  
根据近岸海域的富营养化普遍受营养盐限制的特征,提出了潜在性经的概念,并在此 提出了一种新的富营养化分级标准及相应的评价模式,运用该模式分别评价了厦门海域及中国近海的富养化程度。结果表明,厦门东海域敞 于贫营养水平,而西海域则为磷限制潜在性营养水平;与厦门西海域相近,中国近海主要河口、海湾总体上处于磷限制或磷中等限制潜在性富营养水平。  相似文献   

18.
以生态系统管理为工具开展海岸带综合管理   总被引:5,自引:0,他引:5  
本文从海岸带和海岸带综合管理的几大特征出发 (包括海岸带的中心地带———海 陆生态交错带、海岸带综合管理需要解决的主要问题———生态环境危机、海岸带综合管理的管理对象———社会 经济 自然复合生态系统等方面 ),提出生态学应成为海岸带综合管理的主要科学依据,海岸带综合管理应遵循并且充分运用生态学的理念和方法;文章通过对生态系统管理与海岸带综合管理的比较分析,指出生态系统管理正是生态学中有助于海岸带综合管理的最佳工具,海岸带综合管理应以生态系统管理为基础,并进一步阐述了生态系统管理在海岸带综合管理规划中的具体运用.  相似文献   

19.
浙江沿岸海域浮游动物的分布特征   总被引:4,自引:0,他引:4  
2003年和2004年的夏、秋季对浙江沿岸(27°05′~30°54′N、121°04′~123°19′E)50 m等深线(禁渔线附近,下称外侧海域,站号为P1至P20)和10 m等深线(下称内侧海域,站号为1至17)37个采样站大、小潮汛浮游动物的种类组成、数量分布、优势种及群落特征进行了调查和分析.在调查海区被发现的浮游动物共有234种,属19个大类,其中桡足类66种,水母类42种,浮游软体类、端足类和毛颚类各13种,浮游多毛类9种,糠虾7种,介形类和樱虾各6种,被囊类5种,涟虫和磷虾各4种,枝角类3种,另有各种浮游幼体、仔鱼30种及其它.浮游动物的生物量均值分布是:内侧海域为289.9±43.4 mg/m3,大潮汛为258.9±73.6 mg/m3,小潮汛为320.8±47.3 mg/m3;外侧海域为318.9±49.8 mg/m3,大潮汛为390.5±89.1 mg/m3,小潮汛为247.2±41.4 mg/m3.浮游动物的丰度均值分布是:内侧海域为751.2±138.4个/m3,大潮汛为531.8±94.4个/m3,小潮汛为971.5±253.2个/m3;外侧海域为816.8±137.2个/m3,大潮汛为1 041.0±243.8个/m3,小潮汛为592.5±111.8个/m3.本次调查的结果表明,桡足类对浮游动物丰度的贡献最大,其余依次为毛颚类、水母类、被囊类和浮游幼虫,它们是浮游动物组成数量的主要类群.调查海区出现优势度大于0.02的种类有15种,内侧海域有9种,外侧海域有10种,其中有4种是内、外侧海域共有种.就潮汛和纬度而言浮游动物群落结构指数无明显区别,丰富度、多样性指数和均匀度指数较高而单纯度低,群落结构状态良好.但各类指数变幅较大(种类数为16~55,丰富度为1.73~6.77,单纯度为0.06~0.54,多样度为1.67~4.51,均匀度为0.33~0.87),表明了浮游动物群落结构的不稳定性还存在.根据调查海区浮游动物的生态习性和分布特点,可将其划分为近岸低盐、沿岸暖温、近海暖水、暖水广布和热带外海5个生态类型,其中以近海暖水和暖水广布性种类为主要类群.  相似文献   

20.
The use of barnacles as biomonitors of metal contamination in coastal waters worldwide is reviewed as a critique compilation of the reported studies and presents resume-tables of available data for future reference. The barnacle body reflects both short and long-term metal level environmental variations and the metal bioaccumulation occurs mainly in their granules (relatively inactive pools). The barnacle body is considered as good biomonitoring material and different barnacle species could bioaccumulate metal concentration ranges of 40–153,000 μg/g of Zn, 20–22,230 μg/g de Fe, 1.5–21,800 μg/g of Cu, 5.9–4742 μg/g of Mn, 0.1–1000 μg/g of Pb, 0.7–330 μg/g of Cd, 0.4–99 μg/g of Ni and 0.2–49 μg/g of Cr. However, as the plates (‘shells’) of barnacle exoskeletons can be affected by metal levels in coastal waters, mainly in their composition and morphology, they are not considered good biomonitoring material. Despite this, the use of a specific barnacle species or group of species in a specific region must firstly be carefully validated and the interpretation of the contaminant bioaccumulation levels should involve specific environmental variations of the region, physiological parameters of the barnacle species and the relationship between the potential toxicity of the contaminant for the environment and their significance for the barnacle species. Barnacles, particularly a widespread cosmopolitan species such as Amphibalanus amphitrite, have a great potential as biomonitors of anthropogenic contamination in coastal waters and have been used worldwide, including Europe (United Kingdom, Turkey, Poland, Croatia, Spain and Portugal), Asia (India and China), Oceania (Australia), North America (Florida, Massachusetts and Mexico) and South America (Brazil). The use of barnacle species as biomonitors of metal contamination in coastal waters is considered an important and valuable tool to evaluate and predict the ecological quality of an ecosystem.  相似文献   

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