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1.
台湾省两个港湾污损生物初步研究   总被引:6,自引:2,他引:6  
研究台湾岛北端八斗子港和南部大鹏湾的污损生物,其湿重两个港均偏小(142和168kg/m2).共记录60个物种,两个港的共有种仅7种.八斗子港的28种中,优势种花石莼、变化短齿蛤、缘齿牡蛎、纹藤壶和冠瘤海鞘.大鹏湾29种动物中,优势种是3种管栖端足类(C.insidiosum,E.brasiliensis,E.hoobeno)、3种海鞘(P.constellotum,D.areolatum,S.canopus)、多室草苔虫和沙筛贝,后者是外来物种,还有双凸双眉藻等12种硅藻.两处的污损生物群落各自反映了亚热带和热带两类半封闭港湾污损生物的生态特点.  相似文献   

2.
The Convention for ballast water management is approaching the threshold of enforcement. Many countries around the world formulate national laws and regulations to mitigate the hazards of non-indigenous aquatic species (NIAS) brought about by the discharge of ballast water from ships. Taiwan’s critical location as an important transportation hub in the Western Pacific Ocean makes it a hot spot for the invasion of NIAS. Therefore, devising strategies for the management of ballast water is urgently needed. This study explores the global trend in ballast water management, and discusses the possible strategies which Taiwan may adopt in response to the Ballast Water Convention, from the perspective of Taiwan’s stakeholders in relation to the ballast water issue. Some of the proper actions that Taiwan should take in the future regarding the management of ballast water include: delineating the area for ballast water exchange, establishing the ballast water declaration system for incoming vessels, assisting shipping companies in installing ballast water treatment systems, determining risk priority for incoming vessels, and inspecting ballast water-related parameters by means of port state control (PSC). In this way, the invasion of NIAS may then be prevented in compliance with the global standards.  相似文献   

3.
This article aims to generate insights into both private governance and partnerships within the shipping industry, but also tries to improve understanding of the complex process of institutionalisation.This is achieved through a case study of the Clean Shipping Project, a public/private partnership that aims to promote sustainability in the shipping industry. A set of enabling and constraining factors are examined that shape the institutionalisation process and determine to what extent the Clean Shipping Project can establish and expand authority as an industry norm.Overall, the Clean Shipping Project cannot yet be considered a full-fledged private governance institution, because of an insufficient level of collaborative advantage mainly due to weak system robustness and unfavourable market characteristics and conditions. However, institutionalisation is an ongoing process and the future outlook for the Clean Shipping Project remains promising. The Clean Shipping Project is certainly a relevant supplement to existing regulations and there is a basic level of commitment and cohesion within the partnership, so it is not unlikely that in the future this initiative may help to uncouple growth in shipping activities from environmental harm.  相似文献   

4.
From June 1984 to May 1985, monthly and seasonal panel tests of fouling organisms were carried out on rafts at Tuoji Island. Seventy - three species were obtained. The occurring frequencies of the following species are all at least 30%: Ectocarpus confervoides, Polysiphonia urceolata, Tubularia mesembryanthmum, Cfytia edwardsi, Tubulipora pulchra, Celleporella hyalina, Mytilus edulis, Hiatella arctica, Caprella acanthogaster, Corophium crassicome, Jassa cf.falcata and Podocerus cf . inconspicuus. Large or calcareous species are not dominant ones. The wet weight is comparatively light, the yearly wet weight being 9.12 kg m-2. Attaching seasons of major species are from June to October and no bio - attachment occurs between January and April. Fouling organisms at Tuoji Island differ rather greatly from those in the harbours along the continental coast, showing the charcteristics of fouling organisms in the northern island harbours of China.  相似文献   

5.
The main objective of recent international legislative measures and policies concerning marine ecosystems is to ensure sustainable environmental management to maintain a good status for marine waters, habitats and resources, with the ultimate target of achieving an integrated ecosystem-based approach to management. Because bioinvasions pose significant threats to marine ecosystems and the goods and services these provide, non-indigenous species (NIS) are included in the more recent legislative documents. A major challenge for the scientific community is to translate the principles of the legislative directives into a realistic, integrated ecosystem-based approach and at the same time provide stakeholders with best practices for managing NIS. The aim of this paper, prepared by members of the Working Group on Introductions and Transfers of Marine Organisms (WGITMO) of the International Council for the Exploration of the Sea (ICES), is to provide guidance for the application of NIS related management in the European Union Marine Strategy Framework Directive (MSFD). Ten recommendations, including NIS identification, standardization of sampling and data, indicators, propagule pressure and management issues are considered in this paper. While most of these suggestions were developed to improve the implementation of the MSFD, several may be more widely applicable.  相似文献   

6.
One of the main challenges to facilitate the classification of water bodies is to identify direct relationships between anthropogenic pressures and the behavior of biological organisms such as macrophytes in different environments including transitional areas. The investigation of many lagoons and ponds described here shows that macrophyte variables and the community composition have strong and univocal relationships with ecological parameters that are a measure of anthropogenic pressure on the ecological status of water bodies. The areas surveyed represent about 78% of the Italian transitional waters (169 sites sampled both in spring and fall). Anthropogenic impacts affect the availability of nutrients in the water column and surface sediments, causing changes in water transparency and phytoplankton concentration (as chlorophyll‐a [Chl‐a]) that act as the main drivers of variation for macrophyte assemblages, changing species dominance and the conditions that govern their presence or absence. The response of macrophytes to anthropogenic pressure is quite similar in all the examined transitional environments, even when the basin morphology, species richness and composition are different. Some taxa and species assemblages are so sensitive to environmental changes that monitoring them can be considered the most suitable and rapid method for assessing the quality of the environment they inhabit.  相似文献   

7.
The introduction of exotic marine species has caused considerable economic and ecological damage around the world. Some of these species possess adaptations such as secondary metabolites which facilitate their successful invasion into new areas. In this study we tested two hypotheses: (i) crude extracts produced by two invasive hard corals Tubastraea coccinea and Tubastraea tagusensis, introduced to the southwest Atlantic, inhibit predation by generalist fish; (ii) substances found in the crude extracts of both species reduce or enhance the settlement of other organisms. In an in situ palatability bioassay the extract of T. tagusensis reduced predation by generalist fish. The extracts of both species of coral showed species‐specific effects on fouling organisms in in situ gel plate bioassays. Control and extract plates had similar total cover, although plates with extracts had significantly fewer Cladophora sp., and Lithophyllum sp. was only detected on control gels. In contrast, a hydrozoan was only found on plates with extracts and overall community ordination demonstrated clear differences in the fouling communities between treatments. These results demonstrate that both coral species have chemical substances which can bring about a negative interaction with potential fish predators and competitors such as algal and invertebrate foulers and the advantage gained could explain their success in invading new regions to the detriment of local fauna and flora.  相似文献   

8.
A brief review of the published evidence of current deposits around Italy is the occasion to test the robustness of matching bottom current velocity models and seafloor morphologies to identify contourite drifts not yet documented. We present the result of the regional hydrodynamic model MARS3D in the Northern Tyrrhenian and Ligurian Sea with horizontal resolution of 1.2 km and 60 levels with focus on bottom current: data are integrated over summer and winter 2013 as representative of low and high intensity current conditions.The Eastern Ligurian margin is impacted by the Levantine Intermediate Water (LIW) with modeled mean velocity of bottom current up to 20 cm s−1 in winter 2013 and calculated bottom shear stress exceeding 0.2 N m−2 in water depth of 400–800 m. By crossing this information with seafloor morphology and geometry of seismic reflections, we identify a sediment drift formerly overlooked at ca 1000 m water depth. The Portofino separated mounded drift has a maximum thickness of at least 150 m and occurs in an area of mean current velocity minimum. Independent evidence to support the interpretation include bottom current modelling, seafloor morphology, seismic reflection geometry and sediment core facies. The adjacent areas impacted by stronger bottom currents present features likely resulted from bottom current erosion such as a marine terrace and elongated pockmarks.Compared to former interpretation of seafloor morphology in the study area, our results have an impact on the assessment of marine geohazards: submarine landslides offshore Portofino are small in size and coexist with sediment erosion and preferential accumulation features (sediment drifts) originated by current-dominated sedimentary processes. Furthermore, our results propel a more general discussion about contourite identification in the Italian seas and possible implications.  相似文献   

9.
10.
自然资本评估是研究生态系统服务与社会经济发展的重要方式。由于海洋具有特殊性和复杂性、开放性、流动性和多层次耦合性等特点,海洋自然资本评估方法的研究进展缓慢。能值分析理论通过能值转换率将生态系统内流动和储存的各种不同类别的能量和物质转换为同一标准的能值,可衡量和比较不同等级的能量价值,系统完整地反映自然资本价值,这一特点是其他评估方法所缺乏的。为精确量化海洋生物资本价值,本研究引入海洋食物网信息能流图和生态系统能量传递规律,提出了生物能值转换率的经验公式,即Tn=T1·E^1-nL(T1为初级生产者的太阳能值转换率,n为营养级,EL为林德曼效率)。为验证经验公式的可行性,选用相关案例进行了研究,得到海洋食物网中不同食性生物所处营养级及其相应的能值转换率。经验公式有一定误差,具体应用时应通过调研文献和相关数据,确定关键参数的取值范围以提高准确性。本研究得出的经验公式简化了海洋生物能值转换率的计算方法,促进了能值分析理论在海洋自然资本评估中的进一步应用。  相似文献   

11.
肖鹏  杨坤德  雷波 《海洋工程》2016,(4):591-601
The shipping noise properties in the deep ocean are studied. Shipping noise exhibits the strong dual-horned directionality features in the flat-seabed ocean, and its directional density can be modeled by a Von Mises distribution. With the explicit expression for the directional density function, the spatial coherence functions of shipping noise are also derived, and the relative features are studied. The research result shows that the properties of shipping noise are different from the ambient noise of other sources, and it can be used for the sonar array design. The model is well matched with the experimental result, and it can be extended to the situations when the ambient noise exhibits the dual-horned structure.  相似文献   

12.
13.
Meiobenthic data from two microtidal sandy beaches of the eastern Mediterranean (Crete, Greece) were used to investigate patterns of both alpha and beta diversity in space and time. Copepod assemblages and environmental variables related to sediment characteristics, morphodynamics and food were studied over a year at four distinct habitats at each beach; the retention, resurgence and saturation zones of Salvat's intertidal scheme (midlittoral zone), and the surf zone of the sublittoral. Αlpha diversity analysis indicated similar species richness at both beaches when the whole 13-month data set was considered but was higher at the sheltered site when each sampling period was examined separately. Both beaches supported higher diversity in the sublittoral zone. Species richness increased seawards at the midlittoral zone of the sheltered site whereas, no pattern was evident at the exposed site, where the intense hydrodynamic conditions homogenized the sediments. Beta diversity increased markedly towards the sublittoral, indicating greater differences in alpha diversity between the sublittoral and the midlittoral zone. Species turnover was more variable at the exposed beach and at the most landward stations, where environmental conditions change often between extremes. A proportion of the variation in alpha diversity was explained by food availability at both beaches and additionally by grain size at the sheltered site. However, no environmental variable explained beta diversity patterns. Although the results of our study support the hypothesis of Multicausal Environmental Severity proposed for sandy beach macrofauna, we believe the classic Intermediate Disturbance Hypothesis is a more appropriate framework for the meiofauna communities of the studied sites.  相似文献   

14.
三唑磷对四种水生生物的毒性及安全评价研究   总被引:21,自引:0,他引:21  
本文研究了三唑磷对小球藻、卤虫、南美白对虾、泥蚶四种水生生物的急性毒性作用,结果显示,三唑磷对小球藻的48h的EC50为24μg/dm^3,72h的EC50为15μg/km^3;对卤虫的24hLC50为1.64mg/dm^3,48hLC50为0.8mg/dm^3;对南美白对虾仔虾的48hLG0为3.2μg/dm^3,96hLC50为1.1μg/dm^3。;对泥蚶的48hLC50为21.0mg/dm^3,96hLC50为10.2mg/dm^3。三唑磷对小球藻、卤虫、南美白对虾为高毒农药,泥蚶对三唑磷有很强的耐受力。  相似文献   

15.
In this study, the development of the technique APCI+ LC/MS/MS allowed the detection of phenanthrene, pyrene and metabolites of alkyl homologs in fish bile (in situ) and in urine of crabs. Laboratory experiments were carried out exposing crabs from an unpolluted mangrove (Barra de Guaratiba) to phenanthrene, and to the alkylated homologs 1-methyl phenanthrene and 2,6,9-trimethyl phenanthrene. Urine samples were collected at 0, 24, 48, 72, and 96 h. Fishes were captured from strategic sites from Guanabara Bay. Hydroxylated metabolites of phenanthrene, epoxides, orthoquinone and glucoside conjugates were identified in both samples. The method APCI+ LC/MS/MS showed to be effective in a preliminary assessment of phenanthrene metabolite formation, although the low concentrations of 1-methyl phenanthene and 2,6,9-trimethyl phenanthrene did not allow a systematic evaluation of data. The method, however, proved to be excellent tool for studies of PAHs metabolites due to the high selectivity, sensitivity and separation attained.  相似文献   

16.
The aim of this work was to monitor levels of Cd, Cu, Pb, Zn and Fe in sediments, mussels (Mytilus edulis chilensis) and limpets (Nacella magellanica) from the Industrial zone (IZ); fuel dock (FD) and Ushuaia Peninsula (UP) on the Beagle Channel. In sediments, seasonal variations showed high values of Cu and Pb in spring and Zn in autumn. Comparing among sites, Cd concentration was superior in UP (2.07 μg/g); while Pb was maximum in FD (41.00 μg/g). In mussels, a higher bioaccumulation in winter was found. Mussels from UP showed the highest bioaccumulation of Cu (5.95 μg/g) and those from FD presented the highest of Zn (170.15 μg/g). A seasonal trend was not found for limpets, while differences among sites were observed for Cd being the highest at IZ (3.02 μg/g). Although pollution level found was low, anthropic activities at the studied sites could result in deterioration, further monitoring is recommended.  相似文献   

17.
Arsenic is a widely distributed element in the marine environment. Inorganic and organic compounds have extremely different toxicological effects, and their characterization is thus of great utility when monitoring and assessing the impact of arsenic pollution. In this study both the levels of total arsenic and its chemical speciation were analyzed in several marine organisms collected from Cienfuegos Bay (Cuba) following an episode of acute As-contamination. Fish from the more impacted site were characterized by elevated concentrations of arsenic (up to 500 microg/g d.w.) and inorganic species represented the predominant forms in muscle tissues of these organisms.  相似文献   

18.
Engineered nanoparticles (ENPs) have been produced by nano-biotech companies in recent decades to generate innovative goods in various fields, including agriculture, electronics, biomedicine, manufacturing, pharmaceuticals and cosmetics. The nano-scale size of the particles can confer novel and significantly improved physical, chemical and biological properties to scientific phenomena and processes. As their applications to science and technology expand, the need to understand the putative noxious effects of ENPs on humans and ecosystems is becoming increasingly important. ENPs are emerging as a new class of pollutants with eco-toxicological impacts on marine ecosystems because the particles can end up in waterways and reach the sea. Recent laboratory studies in invertebrates and fishes suggest that exposure to ENPs could have harmful effects. Because there is not much data available for gauging the effects of ENPs on marine wildlife, the ultimate ecotoxicological impacts of chronic exposure to ENPs should be investigated further using laboratory tests and field studies. We propose the use of model organisms to understand the molecular pathways involved in the mechanisms that may be affected by exposure to ENPs. Sensitive and innovative molecular methods will provide information regarding the hazards of ENPs that may exist in the marine environment. Model organisms that have not been conventionally used for risk assessment and the development of eco-toxicogenomic approaches will result in an improved understanding of the mechanistic modes of action of contaminating ENPs in the marine environment.  相似文献   

19.
《Progress in Oceanography》2007,72(2-3):117-120
We briefly introduce the different chapters of this special issue which review the current knowledge and understanding of the biology and ecology of Centropages typicus obtained over the last 30 years. The papers are grouped into two major theme areas: the first five papers review behaviour, feeding, metabolism, growth and development, and reproduction, and the four following papers have a regional focus dealing with temporal and spatial distribution in the Mediterranean Sea and in the North Atlantic shelf areas. The findings reviewed in the two groups of papers converge to explain why C. typicus is such a very successful copepod species in these coastal areas. In the different chapters, similarities and differences with congeneric species (C. velificatus, C. hamatus, C. brachiatus, C. chierchiae, C. furcatus, and C. abdominalis) have been explored where these are known.  相似文献   

20.
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