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海洋资源—动植物、微生物、矿产、加工、养殖与生物经济-138资料网
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海洋资源—动植物、微生物、矿产、加工、养殖与生物经济

Defining and estimating global marine fisheries bycatch
Unselective fishing catches non-target organisms as ‘bycatch’—an issue of critical ocean conservation and resource management concern. However, the situation is confused because perceptions of target and non-target catch vary widely, impeding efforts to estimate bycatch globally. To remedy this, the term needs to be redefined as a consistent definition that establishes what should be considered bycatch. A new definition is put forward as: ‘bycatch is catch that is either unused or unmanaged’. Applying this definition to global marine fisheries data conservatively indicates that bycatch represents 40.4 percent of global marine catches, exposing systemic gaps in fisheries policy and management.

surplus production model with latent truncation and species targeting, with an application to Papua New Guinean fisheries 海洋鱼类品种跟踪与深加工
This paper first reviews traditional bio-economic models of catch–effort equilibrium and later contributions based on augmented and revised specifications. To overcome some of the pitfalls in fisheries analysis, an approach is formulated which accounts for latent truncation in the fishing fleet, species targeting and non-linear long-term relationships among catch, effort and biomass. The procedure is applied to purse seine and longline offshore marine fisheries in Papua New Guinea, where tuna and other fish resources are believed to be under-exploited on the whole, but selective overfishing is reported to take place. Statistical evidence of incidental truncation is weak, with results being sensitive to the selection of variables. Based on regression diagnostics and expected signs/statistical significance of parameter estimates, non-linear surplus production specifications prove to be more suited than original and unrestricted versions of the conventional approach for modelling the dominant (purse seine) fishery in PNG over the period 1979–2007, with both main and secondary target fishing being found not to exceed the maximum sustainable yield. In either case, policy implications of these results should be pondered against underreporting of official fish catches.

The importance of oceanographic fronts to marine birds and mammals of the southern oceans 海鸟的作用与意义

During the last 30 years, at-sea studies of seabirds and marine mammals in the oceans south of the Subtropical Front have described an association with major frontal areas. More recently, the advancement in microtechnology has allowed the tracking of individuals and investigations into how these marine predators actually use the frontal zones. In this review, we examine 1) the relative importance to apex predators of the different frontal zones in terms of spatial distribution and carbon flux; 2) the processes that determine their preferential use; and 3) how the mesoscale dynamics of frontal structures drive at-sea foraging strategies of these predators. We review published results from southern

waters and place them in a broader context with respect to what has been learned about the importance of fronts in oceans farther north.

Some fronts constitute important boundaries for seabird communities in southern waters. At a mesoscale the maximum values of seabird diversity and abundance correspond to the location of the main fronts. At-sea surveys show a strong curvilinear correlation between seabird abundance and sea surface temperatures. High mean species richness and diversity for whales and seabirds are consistently associated with the southern water mass boundary of the Antarctic Circumpolar Current, the Subtropical Front and the Subantarctic Front; in the case of the Polar Front mean seabird densities are more variable. At small-scales, variation in seabird occurrence has been directly related to the processes at fronts in a limited number of cases. A significant positive relation was found between some plankton feeding species and frontal temperature gradient–phytoplankton variables.

Telemetric studies have revealed that several apex predators (penguins, albatrosses, seals) perform long, directed foraging trips either to the Subtropical front or Polar Front, depending on locality. Seabirds with low flight costs, such as albatrosses, are able to reach fronts at long distances from colonies, showing variable foraging strategies as a function of the distances involved. Diving birds such as King penguins, that travel at a higher cost and lower speed, rely on the predictable spatial distribution of mesopelagic fish found close to the Polar Front. They may use the currents associated with eddies as oceanographic cues in the active search for frontal zones. Once in these areas they dive preferentially in and below the depth of the thermocline where catches per unit effort are high. Elephant seals concentrate foraging activity principally inside or at the boundary of cyclonic eddies. These mesoscale features appear to offer exceptional productivity favourable for foraging by various diving top predators.

The connection between biophysical parameters at fronts and predators is likely to be made through biological enhancement. Top predators appear to forage at locations where prey are advected by physical processes and others where prey are produced locally. Long-term research on at-sea distributions and demographic parameters of top predators are essential to assess the consequences of potential shift in front distributions in relation to global warming. Such environmental changes would add to the impact of fish extraction by the industrial fisheries on the southern food webs.

Marine molecular biology: An emerging field of biological sciences 海洋分子生物学 一个分子生物学的新兴领域
An appreciation of the potential applications of molecular biology is of growing importance in many areas of life sciences, including marine biology. During the past two decades, the development of sophisticated molecular technologies and instruments for biomedical research has resulted in significant advances in the biological sciences. However, the value of molecular techniques for addressing problems in marine biology has only recently begun to be cherished. It has been proven that the exploitation of molecular biological techniques will allow difficult research questions about marine organisms and ocean processes to be addressed. Marine molecular biology is a discipline, which strives to define and solve the problems regarding the sustainable exploration of marine life for human health and welfare, through the cooperation between scientists working in marine biology, molecular biology, microbiology and chemistry disciplines. Several success stories of the applications of molecular techniques in the field of marine biology are guiding further research in this area. In this review different molecular techniques are discussed, which have application in marine microbiology, marine invertebrate biology, marine ecology, marine natural products, material sciences, fisheries, conservation and bio-invasion etc. In summary, if marine biologists and molecular biologists continue to work towards strong partnership during the next decade and recognize intellectual and technological advantages and benefits of such partnership, an exciting new frontier of marine molecular biology will emerge in the future.

Southern Ocean seaweeds: A resource for exploration in food and drugs 南海海草资源作为食品与医药原料的开发与利用

Benthic macroalga or seaweed, a wonder plant in the sea, has been attracting the human mind since centuries. Countries of south and south East Asia have put in extensive use of this plant for various purposes such as food, feed, fodder, etc. Development of seaweed in these countries was favored by their ready availability and proximities to centers of human population that were particularly concentrated in coastal areas. In the beginning, those seaweed species that could be used for food were the first to be utilized and later the other species were found to yield industrial, medicinal, pharmaceutical and cosmetic products.

A number of constraints will be required to be adapted if world's seaweed industry is to be developed and stabilized. This is mainly because of uncertainty in supply of raw material and sudden burst in demand that occur in cycles. The seaweed resources have undergone successive periods of over exploitation and neglect. Alternatively, new areas shall have to be explored which could supply rich and high quality seaweeds. The Southern Ocean has immense potential for attracting urgent attention for development and exploitation of seaweed resources.

A number of investigations are underway to assess the uses of Antarctic seaweeds. Recently, an active ingredient from Antarctic seaweed has been identified, which blocks the effects of metalloproteinase, an enzyme that accelerates the skin aging process. A skin care products derived from polar seaweeds has been a latest craze in France and are dedicated to men between 25 and 50 years of age. Antarctic red algae have recently been identified for their chemodiversity, containing compounds possessing antibacterial and other inhibitive properties to marine animals. The important fact remains that before we go for actual harvesting it is necessary that we have full details of their ecophysiology and annual cycle of occurrence at particular region and devise a legal framework after extensive debate with experts, for sustainable use of this valuable resource.

Predicting the impact of ocean acidification on benthic biodiversity: What can animal physiology tell us? 海洋动物资源与生物多样性的启示意义 海洋里的保护生物学
For the past 200 years, the oceans have been absorbing carbon dioxide at an unprecidented rate. It is now evident that this ongoing process has already significantly altered seawater carbon chemistry at a global scale and will continue to do so for hundreds of years to come; a phenomenon termed “ocean acidification”. The challenge currently facing scientists is to predict the long term implications of ocean acidification for the diversity of marine organisms and for the ecosystem functions this diversity sustains. This challenge is all the more difficult considering that empirical data which specifically address the impact of ocean acidification on marine biodiversity are currently lacking. In the face of growing political and public pressure to provide answers, what predictions can be made and how reliable are the assumptions on which those predictions depend? Here we review the extent to which the few existing data, and understanding gained from previous physiological studies, can be used to make predictions for marine biodiversity. In doing so we also scrutinise some established paradigms concerning the impact of hypercapnia, resulting from seawater acidification, on marine organisms.

Bio-leaching of valuable metals from marine nodules under anaerobic condition 金属微量元素对于不同生活环境的海生生物/生命的价值和意义
The present paper studies anaerobic bio-leaching of manganese nodules by Thiobacillus ferrooxidans separated from mining water. With the addition of suitable nutrient and reductant, the metals existing in the nodules, such as Cu, Co, Ni and Mn can be leached effectively in an acidic and anaerobic system under ambient temperature in 3 days. Manganese oxide and nickel sulfide participate in the respiration of the microbe as electron acceptor and donor respectively. Meanwhile, the ferric/ferro ions act as electron shuttles to accelerate the process.

The nature and extent of organisms in vessel sea-chests: A protected mechanism for marine bioinvasions
A total of 150 different organisms, including one plant species and 12 animal phyla were identified from sea-chests of 42 vessels visiting or operating in New Zealand between May 2000 and November 2004. Forty-nine percent of organisms were sessile, 42% mobile adults and the remaining 9% sedentary. Decapods were the most represented group with 19 species present among 79% of vessels. Forty percent of organisms were indigenous to New Zealand, 15% introduced, 10% non-indigenous, and 35% of unknown origin. Sea-chests have the potential to (1) transfer non-indigenous organisms between countries across oceanic boundaries; and (2) disperse both indigenous and introduced organisms domestically. The occurrence of adult mobile organisms is particularly significant and indicates that sea-chests may be of greater importance than ballast water or hull fouling for dispersing certain marine species. These findings emphasise the need to assess and manage biosecurity risks for entire vessels rather than different mechanisms (i.e., ballast water, hull fouling, sea-chests, etc.) in isolation.

Modelling spatial and temporal scales for spill-over and biomass exportation from MPAs and their potential for fisheries enhancement 海生生物聚集地/聚居区的勘探与物种保护和鱼群数量扩增繁殖
Marine protected areas (MPAs) are considered as a tool for marine conservation and sustainable fishery resource management. Improvements in fishery yields should take place via the spill-over of individuals from the reserve. In general, it has been demonstrated that MPAs affect the density and biomass of the organisms within them, however, little evidence has been found in order to assess the exportation of individuals across their boundaries. In this study, a simple model involving population growth, harvest, and the diffusion coefficient for individuals was used to explore the effects of protection on populations inside the reserve and the spill-over of individuals to the fished area. The model showed that biological responses inside marine reserves appear to develop quickly, reaching mean levels within a short (1–5 year) time period. Mean population abundance is always higher inside the reserve and highlights the effectiveness of protection, particularly when there is strong fishing pressure outside the reserve. However, reserves smaller than 2000 m radius show significantly lower levels of abundance inside than larger sites. Large MPAs (i.e. about 2000 m in radius) offer nearly the maximum capacity for recovery (close to 100% of the system carrying capacity) and nearly the maximum flux of individuals per unit boundary length. Very large MPAs (i.e. larger than 6000 m in radius) could be a guaranteed means of providing resilience in order to prevent population crises, with the added advantage that the flux of individuals is slightly higher at larger distances from the boundary. However, in practice they provide no further advantage towards increasing the density of individuals or the exportation of biomass, and a network of smaller MPAs could be more beneficial, both from the point of view of conservation and of benefits to fisheries.

Sustainability of exploited marine ecosystems through protected areas: A viability model and a coral reef case study 海洋生态环境的可持续性循环发展 过度开发的防护

Overexploitation of marine resources remains a problem worldwide. Many works advocate for the use of marine reserves as a central element of future stock management in a sustainable perspective. In the present paper, we address the influence of protected areas upon fisheries sustainability within an eco-systemic framework through a dynamic bio-economic model integrating a trophic web, catches and environmental uncertainties. The model is spatially implicit. The evaluation of the ecosystem is designed through the respect along time of constraints of both conservation and guaranteed captures. Using the mathematical concept of invariance kernel in a stochastic context, we define different MPA effects according to biodiversity, catches or mixed points of view. Numerical simulations inspired from data of Aboré coral reef reserve in New Caledonia illustrate the main concepts. In this case, it is pointed out how MPA conservation effect is not necessarily conflicting with MPA catches effect. It is shown that such a co-viability requires medium exploitation rate. Moreover, the climatic changes represented by rise in cyclonic events seem to reinforce these assertions.

Marine reserves: A bio-economic model with asymmetric density dependent migration
A static bioeconomic model of a marine reserve allowing asymmetric density dependent migration between the reserve and the fishable area is introduced. This opens for habitat or ecosystem differences allowing different fish densities within and outside a reserve, not described in earlier studies. Four management scenarios are studied; (a) maximum harvest, (b) maximum current profit, (c) open access and (d) maximum sustainable yield (MSY) in the reserve. These are all analysed within the Induced Sustainable Yield Function (ISYF), giving the relationship between the fish abundance inside the reserve and the harvesting taking place outside. A numerical analysis shows that management focused on ensuring MSY within the reserve under the assumption of symmetric migration may be negative from an economic point of view, when the area outside the reserve is detrimental compared to the reserve. Furthermore, choice of management option may also have negative consequences for long run resource use if it is incorrectly assumed that density dependent migration is symmetric. The analysis also shows that the optimal area to close, either a more or a less attractive ecosystem for the resource in question, may differ depending on the management goal.

Vitamin E protection in the biochemical adaptation of marine organisms to cold-water environments

Removing vessels from the water for biofouling treatment has the potential to introduce mobile non-indigenous marine species
Vessels found contaminated with biofouling non-indigenous marine species are predominantly removed from the water and treated in vessel maintenance facilities (i.e., slipways, travel lifts and dry-docks).

Using pre-fouled settlement plates to simulate a vessel’s removal from the water for treatment, we demonstrate that a range of mobile organisms (including non-indigenous marine species) may be lost to the marine environment as a consequence of this process. We also determined that different levels of biofouling (primary, secondary and tertiary) and emersion durations (0.5, 5 and 15 min) affected the abundance and composition of mobile taxa lost to the marine environment. Primary biofouling plates lost 3.2% of total animals, secondary plates lost 19.8% and tertiary plates lost 8.2%, while hanging duration had only minor effects. The results suggest that removing vessels contaminated with biofouling non-indigenous marine species from the water for treatment may not be as biosecure as is currently recognised.

Size selection by diamond- and square-mesh Mediterranean demersal trawl fisheries

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A risk analysis framework for aquatic animal health management in marine stock enhancement programmes 海洋动物健康保护与管理实施框架与物种保护和数量储藏扩增
In light of limited supplies of fish from natural populations, stock enhancement is being considered as one means of helping to meet the demand for seafood products from an ever-increasing human population. The technology to produce large numbers of early-life stage aquatic organisms in hatcheries is well-developed, and the use of alien species, although controversial, has also created new fisheries in some countries. Stock enhancement often requires technical interventions in the rearing process of aquatic organisms that may substantially change how an organism interacts with pathogens. Aquatic animal health risk analysis in stock enhancement programmes involves consideration of: the source of animals to be released, the populations to be managed, hazard identification, risk assessment, risk management, quarantine, diagnostic and treatment procedures, mitigation measures, monitoring, reporting the disease status of hatchery and wild populations, and the establishment of aquatic animal health standards. Information and guidelines to assist in aquatic animal health management include the FAO Conduct for Responsible Fisheries, the ICES code of practice on introductions, the OIE aquatic animal health standards, the Asian regional guidelines on health management for the responsible movement of aquatic animals and the WTO's Sanitary and Phytosanitary Agreement.

Animal excrement: A potential biomonitor of heavy metal contamination in the marine environment
To assess the feasibility of using animal excrement to biomonitor the extent of heavy metal contamination in the marine environment, concentrations of mercury (Hg), lead (Pb), copper (Cu) and zinc (Zn) in the fresh excrement of seabirds and marine mammals, along with other biomaterials, from the Arctic,

Antarctica (West and East), and Xisha Archipelago of the South China Sea were determined. Results show that the excrement of marine animals at higher trophic levels generally contained high levels of Hg, demonstrating the biomagnification of Hg through food chains in different remote regions. Significant variations in metal accumulation in the excrements were observed among the distinctive geographical areas, with the highest Hg concentration in Xisha Archipelago and the highest Pb concentration in the Arctic, which reflects different levels of air metal pollution at various sampling locations. Concentrations of Cu in the excrements primarily correlate to the geochemical background levels in the regions. High Cu concentrations were found near the Great Wall Station in West Antarctica where a copper mineralized belt exists. No clear spatial variation pattern was found for Zn accumulation in the excrement. This study shows that animal excrement can be used as bioindicators for the level of metal contamination in the marine environment, with the advantages of easy sampling, accurate detection (i.e., with high levels of metal accumulation), and reconstructing historical metal contamination trends by long-term monitoring of sedimentary excrements. 海水成分与动物生存

Marine biominerals: perspectives and challenges for polymetallic nodules and crusts
Deep sea minerals in polymetallic nodules, crusts and hydrothermal vents are not only formed by mineralization but also by biologically driven processes involving microorganisms (biomineralization). Within the nodules, free-living and biofilm-forming bacteria provide the matrix for manganese deposition, and in cobalt-rich crusts, coccolithophores represent the dominant organisms that act as bio-seeds for an initial manganese deposition. These (bio)minerals are economically important: manganese is an important alloying component and cobalt forms part of special steels in addition to being used, along with other rare metals, in plasma screens, hard-disk magnets and hybrid car motors. Recent progress in our understanding of the participation of the organic matrices in the enrichment of these metals might provide the basis for feasibility studies of biotechnological applications.

Biological importance of marine algae
Marine organisms are potentially prolific sources of highly bioactive secondary metabolites that might represent useful leads in the development of new pharmaceutical agents. Algae can be classified into two main groups; first one is the microalgae, which includes blue green algae, dinoflagellates, bacillariophyta (diatoms)… etc., and second one is macroalgae (seaweeds) which includes green, brown and red algae. The microalgae phyla have been recognized to provide chemical and pharmacological novelty and diversity. Moreover, microalgae are considered as the actual producers of some highly bioactive compounds found in marine resources. Red algae are considered as the most important source of many biologically active metabolites in comparison to other algal classes. Seaweeds are used for great number of application by man. The principal use of seaweeds as a source of human food and as a source of gums (phycocollides). Phycocolloides like agar agar, alginic acid and carrageenan are primarily constituents of brown and red algal cell walls and are widely used in industry.

Impacts of global environmental change and aquaculture expansion on marine ecosystems
The stability of world's reduction fisheries and the global fishmeal market they support is explored through a geographically-specific, global bio-economic model, driven by three interactive forcing factors: climate-driven changes in the biological production of regional fish stocks, the potential global expansion of aquaculture demand for fishmeal and differential management schemes. The model captures approximately 85% of the world's fishmeal and fish oil data and is driven by trade data from the period 1997–2004. Twenty-year model simulations are conducted considering, on the production side, a random recruitment variability of the fish stocks supporting all regional production systems, plus an El Nio-type perturbation altering the productivity of Peruvian and Chilean stocks. The production systems are confronted with two alternative aquaculture expansion scenarios, allowing for the quantification of the synergism between regional climate-driven fluctuations and economic globalization of marine commodities in determining sustainable and unsustainable pathways for the world's reduction fisheries. The simulation results are compared to trends in regional climate indices, trade information from international markets and aquaculture and small pelagic fisheries data. The work pioneers the quantification of the double exposure created by climate variability and change and economic globalization on particular natural resources and explains the stakes involved in the development of fishmeal trade for global aquaculture expansion for marine fish populations. The results demonstrate that regional stocks can recover from climate-driven fluctuations unless these act simultaneously to an expansion in international market demand, and are subject to sub-optimal management schemes. It is argued that the dynamics of the fishmeal price since the early 1990 already responds to the balance between climatic variability in production and market developments, as mimicked by the model. Furthermore, under sub-optimal management scenarios, a sequential pattern of overexploitation emerges as an endogenous property of the interaction between regional climatic disturbances and a globalized trade system. It is concluded that the way we manage climate impacts, both at regional and global level, will determine the sustainability of the world's reduction fisheries, a conclusion that could be extended to other, similarly affected, natural resources.




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