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1.
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2.
《Oceanologica Acta》2002,25(5):199-206
Central to the development of an inventory of marine life and improved conceptual understanding of the mechanisms that dynamically shape species distribution patterns is the implementation of strategies aimed at enhancing assimilation and access to existing biogeographical information. Using the Internet as a medium, the Gulf of Maine Biogeographic Information System (GMBIS) project provides a framework and a set of reusable tools for the integration, visualization, analysis and dissemination of diverse types of biogeographical and oceanographic information. End-to-end viability of this approach is demonstrated in the context of a series of scientific storylines and a pilot application for the Gulf of Maine (GoM), a well-studied ecosystem that has been subject to large-scale perturbation due to overfishing. Databases at the core of the information system include those of the DFO Bedford Institution of Oceanography and Atlantic Reference Center, which are the product of multidisciplinary research efforts over the last several decades. Development of GMBIS may serve not only as a model for OBIS, but it may also provide a tool supporting new international and Canadian directives for integrated marine resource management. This paper summarizes the status of the GMBIS project, currently in its final phase, and outlines possible future directions in information system development for the CoML.  相似文献   

3.
As part of a project comparing the structure and function of four marine ecosystems off Norway and the United States, this paper examines the oceanographic responses to climate forcing, with emphasis on recent changes. The four Northern Hemisphere ecosystems include two in the Pacific Ocean (Bering Sea and Gulf of Alaska) and two in the Atlantic Ocean (Georges Bank/Gulf of Maine and the Barents/Norwegian Seas). Air temperatures, wind forcing and heat fluxes over the four regions are compared as well as ocean hydrography and sea-ice conditions where seasonal sea ice is found. The long-term interannual variability in air temperatures, winds and net heat fluxes show strong similarity between adjacent ecosystems and within subregions of an ecosystem, but no significant correlations between Pacific and Atlantic ecosystems and few across the Atlantic. In spite of the lack of correlation between climate forcing and ocean conditions between most of the ecosystems, recent years have seen record or near record highs in air and sea temperatures in all ecosystems. The apparent causes of the warming differ. In the Atlantic, they appear to be due to advection, while in the Pacific temperatures are more closely linked to air-sea heat exchanges. Advection is also responsible for the observed changes in salinity in the Atlantic ecosystems (generally increasing salinity in the Barents and Norwegian Seas and decreasing in the Gulf of Maine and Georges Bank) while salinity changes in the Gulf of Alaska are largely related to increased local runoff.  相似文献   

4.
Major features of four marine ecosystems were analyzed based on a broad range of fisheries-associated datasets and a suite of oceanographic surveys. The ecosystems analyzed included the Gulf of Maine/Georges Bank in the Northwest Atlantic Ocean, the Norwegian/Barents Seas in the Northeast Atlantic Ocean, and the eastern Bering Sea and the Gulf of Alaska in the Northeast Pacific Ocean. We examined survey trends in major fish abundances, total system fish biomass, and zooplankton biomasses. We standardized each time series and examined trends and anomalies over time, using both time series and cross-correlational statistical methods. We compared dynamics of functionally analogous species from each of these four ecosystems. Major commonalities among ecosystems included a relatively stable amount of total fish biomass and the importance of large calanoid copepods, small pelagic fishes and gadids. Some of the changes in these components were synchronous across ecosystems. Major differences between ecosystems included gradients in the magnitude of total fish biomass, commercial fish biomass, and the timing of major detected events. This work demonstrates the value of comparative analysis across a wide range of marine ecosystems, suggestive of very few but none-the-less detectable common features across all northern hemisphere ocean systems.  相似文献   

5.
The mean seasonal cycle and distribution of various life history stages of C. finmarchicus throughout the Georges Bank (GB)-Gulf of Maine (GOM) region were characterized based on 5966 MARMAP zooplankton samples collected during 106 surveys over a 10-year period (autumn 1977–autumn 1987). A high degree of seasonal and spatial variability in C. finmarchicus abundance throughout the region was evident in contoured portrayals of data, grouped into standard stations and 2-month “seasons”.Eight subareas of the Gulf of Maine-Georges Bank region were identified through cluster analysis of standard stations having similar seasonal patterns in mean abundance of C. finmarchicus stages C3, C4, C5 and adults. These were the northern Gulf of Maine (Northern GOM); southern Gulf of Maine (Southern GOM); Scotian Shelf-coastal Gulf of Maine (Scotian-Coastal GOM); Mass Bay; tidally mixed Georges Bank (Mixed GB); tidal front on the Bank separating mixed from seasonally stratified water (Tidal Front GB); seasonally stratified water on the Bank (Stratified GB) and the Continental Slope adjacent to Georges Bank (SLOPE).A distinct seasonal abundance cycle was present in all subareas, but, the magnitude and timing of annual maxima varied greatly among subareas. Peak abundance was reached early (March–April) in Mixed GB, Tidal Front GB and Mass Bay, and late (July–August) in Northern GOM and Scotian-Coastal GOM. Remaining subareas had maxima in May–June. Abundance increased 10-fold from January–February to March–April and decreased sharply from July–August to September–October in all areas except southern GOM and northern GOM. The amplitude of the annual cycle was weakest in northern GOM and southern GOM, where high concentrations of C. finmarchicus persisted year-round, and strongest in the tidally mixed shallow water on GB, where the sparsest densities of C. finmarchicus occurred most of the year. Abundance curves for the various areas converged in March–April, when C. finmarchicus was ubiquitously very abundant (> 104/10 m2), and diverged from September to December.C. finmarchicus stage distribution in the GB-GOM area was highly negatively correlated with mean water column temperature during the stratified season. This seemed more related to the hydrography of the region, which isolates warmer well mixed Georges Bank from the Gulf of Maine and the stratified areas on the Bank, than to temperature, because Calanus abundances decline on the Bank before water temperatures exceed their preferences.A large part of the spatial and seasonal variation in C. finmarchicus abundance and age structure appears to be tightly coupled to major hydrographic regimes and to major circulation patterns in the region. There was a sharp ecotone between well-mixed Georges Bank and the Gulf of Maine as defined by C. finmarchicus abundance patterns and life history distributions. The ecotone is present year-round but is most apparent during the stratified season (May–October), when thermohaline density gradients and the near-surface current jet along the northern flank are generally strongest. The Gulf of Maine had the highest abundances of C. finmarchicus, and lowest spatial and seasonal variation in the region, while tidally mixed Georges Banks displayed the opposite pattern. This indication of stable population centers in the Gulf of Maine would make it a major source of Calanus in the region, particularly during March–April. Distributional patterns also suggest a strong Calanus influence from Scotian Shelf water in northern Gulf of Maine and on the southern flank of Georges Bank.  相似文献   

6.
The use of artificial reefs in the Arabian Gulf have a history extending back over a century, when date palm trunks, stones, pottery and other materials were sunk in coastal areas to enhance fish catch. Historically, such artificial reefs formed an important component of the socio-economic development of coastal fisheries. In comparison, modern artificial reefs have taken on a variety of forms. The most widely recognized are purpose-build modular artificial reefs designed for the enhancement of fisheries yield, diving, and various other benefits. However, far more common within the Gulf are the large-scale unplanned artificial reefs that have been formed as a result of human activities in the marine system, such as large-scale coastal breakwaters, seawalls, jetties, pipelines, and oil and gas infrastructure. Although there is limited information on the role of these constructions in structuring Gulf marine communities, increasing evidence suggests that abundant and diverse communities of reef fish, coral and other benthos can develop on these structures, with important ecological implications in urbanized coastal areas in the Gulf. However, due to a variety of unintended consequences of artificial reef development such structures may also pose challenges to coastal marine management. We review the current published literature on artificial reefs in the Gulf in order to improve our understanding of the role that these structures play in Gulf coastal ecosystems, and to further develop regional management of artificial reefs. We explore the various types of artificial reef that exist in the Gulf and examine the benefits and challenges that these structures represent for coastal ecology and economics. Such information is essential for our improved understanding and management of these increasingly important ecosystems in the Gulf.  相似文献   

7.
As part of the international MENU collaboration, we compared and contrasted ecosystem responses to climate-forced oceanographic variability across several high latitude regions of the North Pacific (Eastern Bering Sea (EBS) and Gulf of Alaska (GOA)) and North Atlantic Oceans (Gulf of Maine/Georges Bank (GOM/GB) and the Norwegian/Barents Seas (NOR/BAR)). Differences in the nitrate content of deep source waters and incoming solar radiation largely explain differences in average primary productivity among these ecosystems. We compared trends in productivity and abundance at various trophic levels and their relationships with sea-surface temperature. Annual net primary production generally increases with annual mean sea-surface temperature between systems and within the EBS, BAR, and GOM/GB. Zooplankton biomass appears to be controlled by both top-down (predation by fish) and bottom-up forcing (advection, SST) in the BAR and NOR regions. In contrast, zooplankton in the GOM/GB region showed no evidence of top-down forcing but appeared to control production of major fish populations through bottom-up processes that are independent of temperature variability. Recruitment of several fish stocks is significantly and positively correlated with temperature in the EBS and BAR, but cod and pollock recruitment in the EBS has been negatively correlated with temperature since the 1977 shift to generally warmer conditions. In each of the ecosystems, fish species showed a general poleward movement in response to warming. In addition, the distribution of groundfish in the EBS has shown a more complex, non-linear response to warming resulting from internal community dynamics. Responses to recent warming differ across systems and appear to be more direct and more pronounced in the higher latitude systems where food webs and trophic interactions are simpler and where both zooplankton and fish species are often limited by cold temperatures.  相似文献   

8.
The biogeography of macrobenthic communities with large-scale differences in species distribution and abundance was studied along the eastern and western coastal regions of the Gulf of Suez to indicate biodiversity of benthos in relation to the prevailing environmental conditions. In general, benthos have a wide variety of species of mainly polychaet worms, crustaceans, bivalves, and other bottom invertebrates living in burrows in/or on the sediment surface. Coastal development clearly affects the ecosystem after the construction of coastal projects. The highest values of benthic diversity, evenness, richness and dominance are found at the Gulf of Suez （WG 1, WG 3）, Ras Gharib （WG 7, WG 8） and Ras Shukier （WG 9a） by contrast to others. The abundance of macrobenthic organsims along the coasts of Gulf of Suez can be arranged in the following sequence： other groups （34%） greater than crustaceans （25%） greater than polychaetes （22%） greater than molluscs （17%） greater than echinoderms （2%）. The biomass of benthic assemblages at different sampling sites can also be ranked as follows： echinoderms （52%） greater than molluscs （27%） greater than crustaceans （16%） greater than polychaetes （2%） greater than other groups （3%）. Some benthic groups or species indicated a distinctive correlation to pollution sources in the marine ecosystem which obviously increased in the coastal areas due to the extension of the coastal development. These activities needed regular information to establish database for the biology and distribution of marine benthic communities. The density and diversity of benthos are significantly affected by eutrophication at Ain Sukhna, whereas the benthos in the open Gulf of Suez do not seem to be adversely affected by pollution.  相似文献   

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10.
李永祺  张鑫鑫 《海洋与湖沼》2021,52(5):1067-1074
海洋生态学和生物海洋学的研究内容大多交叉、重叠。为利于学科发展,文章在简述学科的产生与定义的基础上,强调学科之间要加强合作,适当分工。建议:海洋生态学侧重研究生物之间的相互关系和对环境的适应性、生存策略,并积极与经济、社会和文化相关学科交叉、融合;生物海洋学侧重于研究生物在海洋环境中的作用和功能,把推进对海洋的认识放在首位,加强与物理海洋学、化学海洋学的耦合,为海洋在地球四大圈层的相互关系中展现活力。据此,以渔业海洋学、海洋生态灾害和生物对地质的作用为例,阐述海洋生态学和生物海洋学的理解及其相互之间关系。  相似文献   

11.
Because climate change challenges the sustainability of important fish populations and the fisheries they support, we need to understand how large scale climatic forcing affects the functioning of marine ecosystems. In the Humboldt Current system (HCS), a main driver of climatic variability is coastally-trapped Kelvin waves (KWs), themselves originating as oceanic equatorial KWs. Here we (i) describe the spatial reorganizations of living organisms in the Humboldt coastal system as affected by oceanic KWs forcing, (ii) quantify the strength of the interactions between the physical and biological component dynamics of the system, (iii) formulate hypotheses on the processes which drive the redistributions of the organisms, and (iv) build scenarios of space occupation in the HCS under varying KW forcing. To address these questions we explore, through bivariate lagged correlations and multivariate statistics, the relationships between time series of oceanic KW amplitude (TAO mooring data and model-resolved baroclinic modes) and coastal Peruvian oceanographic data (SST, coastal upwelled waters extent), anchoveta spatial distribution (mean distance to the coast, spatial concentration of the biomass, mean depth of the schools), and fishing fleet statistics (trip duration, searching duration, number of fishing sets and catch per trip, features of the foraging trajectory as observed by satellite vessel monitoring system). Data sets span all or part of January 1983 to September 2006. The results show that the effects of oceanic KW forcing are significant in all the components of the coastal ecosystem, from oceanography to the behaviour of the top predators – fishers. This result provides evidence for a bottom-up transfer of the behaviours and spatial stucturing through the ecosystem. We propose that contrasting scenarios develop during the passage of upwelling versus downwelling KWs. From a predictive point of view, we show that KW amplitudes observed in the mid-Pacific can be used to forecast which system state will dominate the HCS over the next 2–6 months. Such predictions should be integrated in the Peruvian adaptive fishery management.  相似文献   

12.
《Oceanologica Acta》2002,25(5):255-266
Tagging of Pacific pelagics (TOPP) is a pilot program of the Census of marine life (CoML) that will lead to understanding of pelagic habitat use by marine vertebrates and large squid in the North Pacific. Taking a multispecies approach, the TOPP project will use a range of electronic tag technologies to put the distribution and behavior of pelagic organisms in the context of the oceanography of the North Pacific. Tag-bearing animals will be used as autonomous ocean profilers to enhance sparse oceanographic observations for vast ocean regions. These autonomous ocean samplers will provide unprecedented coverage of the water column structure of the North Pacific. The temporal and spatial data generated by this project will provide an “organism-eye” view of several interactive oceanic regimes in the North Pacific. Twenty target species, including tunas, sharks, pinnipeds, cetaceans, seabirds, and marine turtles, will be monitored with electronic tags. Animal-collected oceanic data will be assimilated into global ocean databases, complement traditional methodologies and be used to help validate nearshore, regional, and basin scale ocean models. As more environmental information is gathered and delivered from the tagged animals, new insights will be obtained about their individual behaviors, as well as how diverse species have separately evolved to forage, reproduce, and survive in the vast pelagic environment. This multi-disciplinary approach will allow a novel merger of biological and physical data to provide a new understanding of the relationship between the movements and behaviors of marine organisms and oceanographic processes in the eastern North Pacific.  相似文献   

13.
This is a review of the study on the oceanic environments relating to the marine living resources carried out since 1947, during more than 35 years which are the period of the authors oceanographic research life for fisheries. Its content consists of describing the outlines of, (1) the oceanographic study of the Subarctic Region of the Northwestern Pacific as the salmon living waters, (2) the study on dilution processes of the effluent in the coastal waters in relation to marine pollution, (3) the oceanographic study on transportation and diffusion of fish eggs and larvae in relation to the recruitment of living resources and (4) the study on forecasting of the fisheries and oceanographic conditions, and a short note on direction of fisheries oceanography expected to be studied in the future.  相似文献   

14.
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   

15.
For the audience or readers to deepen understanding of fisheries oceanography, especially physical fisheries oceanography, this lecture reviews my research work, including clues, failures and management problems encountered during the course of my studies. The contents of this lecture are: (1) introduction, (2) hydrographical feature in and around the Perturbed Area between the Kuroshio and Oyashio Fronts and its fluctuation, (3) conservative properties along a streamline or a trajectory and observation planning, (4) the Kuroshio south of Japan and warm and cold eddies pinched off from the Kuroshio meanders, (5) convergence-divergence of currents and accumulation-dispersal of marine organisms, (6) the Japan Sea (and a part of the East China Sea), and (7) conclusion: approaches to research in fisheries oceanography.  相似文献   

16.
Understanding in climate effects on marine ecosystem is essential to utilize, predict, and conserve marine living resources in the 21s t century. In this review paper, we summariz ed t h e past history and current status of Korean fisheries as well as the changes in climate and oceanographic phenomena since the 1960s. Ocean ecosystems in Korean waters can be divided into three, based on the marine commercial fish catches; the demersal ecosystem in the Yellow Sea and the East China Sea, the pelagic ecosystem in the Tsushima Warm Current from the East China Sea to the East/Japan Sea, and the demersal ecosystem in the northern part of the East/Japan Sea. Through the interdisciplinary retrospective analysis using available fisheries, oceanographic, and meteorological information in three important fish communities, the trend patterns in major commercial catches and the relationship between climate/ environmental variability and responses of fish populations were identified. Much evidence revealed that marine ecosystems, including the fish community in Korean waters, has been seriously affected by oceanographic changes, and each species has responded differently. In general, species diversity is lessening, and mean trophic level of each ecosystem has decreased during the last 3~4 decades. Future changes in fisheries due to global warming are also considered for major fisheries and aquaculture in Korean waters.  相似文献   

17.
The Gulf of California is unique because of its geographical location and conformation. It hosts diverse ecosystems and important fisheries that support industry and provide livelihood to coastal settlements. It is also the site of interests and problems, and an intense interaction among managers, producers, and conservationists. In this report, we scrutinize the abiotic (hydrography, climate, ocean circulation, and chemistry) and biotic (phyto- and zooplankton, fish, invertebrates, marine mammals, birds, and turtles) components of the marine ecosystem, and some particular aspects of climate variability, endemisms, harmful algal blooms, oxygen minimum layer, and pollution. We also review the current conditions and conflicts around the main fisheries (shrimp, small and large pelagic fishes, squid, artisanal and sportfishing), the most important human activity in the Gulf of California. We cover some aspects of management and conservation of fisheries, especially the claimed overexploitation of fish resources and the ecosystems, and review proposals for creating networks of marine protected areas. We conclude by identifying main needs for information and research, particularly the integration of data bases, the implementation of models and paleoreconstructions, establishment of monitoring programs, and the evaluation of fishing impacts and management actions.  相似文献   

18.
This paper describes the main features of the Icelandic marine ecosystem and its response to climate variations during the 20th century. The physical oceanographic character and faunal composition in the southern and western parts of the Icelandic marine ecosystem are different from those in the northern and the eastern areas. The former areas are more or less continuously bathed by warm and saline Atlantic water while the latter are more variable and influenced by Atlantic, Arctic and even Polar water masses to different degrees. Mean annual primary production is higher in the Atlantic water than in the more variable waters north and east of Iceland, and higher closer to land than farther offshore. Similarly, zooplankton production is generally higher in the Atlantic water than in the waters north and east of Iceland. The main spawning grounds of most of the exploited fish stocks are in the Atlantic water south of the country while nursery grounds are off the north coast. In the recent years the total catch of fish and invertebrates has been in the range of 1.6–2.4 million ton. Capelin (Mallotus villosus) is the most important pelagic stock and cod (Gadus morhua) is by far the most important demersal fish stock. Whales are an important component of the Icelandic marine ecosystem, and Icelandic waters are an important habitat for some of the largest seabird populations in the Northeast Atlantic.In the waters to the north and east of Iceland, available information suggests the existence of a simple bottom-up controlled food chain from phytoplankton through Calanus, capelin and to cod. Less is known about the structure of the more complex southern part of the ecosystem. The Icelandic marine ecosystem is highly sensitive to climate variations as demonstrated by abundance and distribution changes of many species during the warm period in the 1930s, the cold period in the late 1960s and warming observed during the recent years. Some of these are highlighted in the paper.  相似文献   

19.
The Continuous Plankton Recorder (CPR) survey has sampled plankton on 14 routes off the coasts of the northeast United States and Canada between 1959 and 2000. Six of these routes are still operating and are sampled on a monthly basis. Some 2047 CPR tows have been made to the end of 2000 and the resulting database represents the most extensive time series of marine plankton available anywhere in the northwest Atlantic. The location and time span of coverage of each route is presented. In addition selected information is presented on:
1. zooplankton abundance as departures from baselines for the northeast US continental shelf;
2. interannual variation in seasonality of Gulf of Maine phytoplankton;
3. zooplankton relationships to local hydrography of the Gulf of Maine and to the North Atlantic Oscillation;
4. time-space matrices of zooplankton abundance and anomalies southeast of New York City;
5. time series of phyto- and zooplankton on the Scotian Shelf;
6. seasonal cycles of Phytoplankton Colour and of zooplankton on the Scotian Shelf and Georges Bank, and in the Gulf of Maine; and
7. monthly abundance of zooplankton in Narragansett Bay, Rhode Island.
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20.
季风驱动下的南海海洋动力过程有着季节性的多尺度变化特征, 显著影响南海海洋生态系统的演化进程。海洋细菌作为海洋生态系统中物质循环和能量流动的重要组成部分, 对环境变化和海洋多尺度动力过程有着积极的响应。将微生物生态过程与海洋动力过程相结合, 研究微生物的群落结构、动态变化及其与海洋环境过程的耦合, 是目前国际海洋科学多学科交叉研究的热点之一。文章以国家自然科学基金重点项目“季风环流影响下的南海海洋细菌多样性特征及其生物海洋学意义”的主要研究成果为基础, 从南海北部上升流、海洋锋面、中尺度涡旋、次中尺度过程及其对海洋细菌多样性和生态系统可能的影响等几个方面, 探讨当前的研究进展和初步研究成果。  相似文献   

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