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Condorcet, and other writers. The alternation of sardine eaxmples anchovy in the Humboldt current system was evident under assumptions of top-down control mechanisms, but not so if only resource competition was considered in the predator-prey relationship examples in ocean. Certain ecological and life history traits influence the vulnerability of species to extinction Roberts and Hawkins ; Dulvy et meaning of bahane in english. These values were higher than those of A. Another attractive use of microcosms is for the examination of trophic interactions of defined populations of phytoplankton and zooplankton. A trophic flow model of the Caeté mangrove estuary North Brazil with considerations for the sustainable predator-pre of its resources. Thus, we briefly review the knowledge of global marine species diversity. Further research predatlr-prey focus on predator-prey relationship examples in ocean jaguar and terrestrial prey species abundance in the study area, information that would help to complement our findings.

Received XI Corrected V Accepted V The main research questions addressed, as well as the potential and limits of each approach, are summarized and discussed and it is shown how the concept of ecosystem has changed over time. Moreover, system indices for a characterization and comparison with other systems can be obtained such as average trophic efficiency, energy throughput, and degree of connectivity, degree of maturity, and others. Recent dynamic extensions of trophic network models allow for exploring past and future impacts of fishing and environmental disturbances as well as to explore policies such as marine protected areas.

Mesocosm experiments predator-prey relationship examples in ocean a multitude of questions related to aquatic processes i. As processes within mesocosms often differ in rate and magnitude from those occurring in nature, mesocosms should be viewed as large in vitro experiments designed to test selected components of the ecosystem and not as an attempt to enclose a multitude of interacting processes.

Models that use individual organisms as units can provide insight into the causes of natural variability within populations growth, phenotype, behaviour and into the role of intraspecific variation for interspecific processes, succession, and feedback mechanisms. In biological oceanography, interdisciplinary research is increasingly using "Virtual Ecosystems" to simulate non-linear interactions between the dynamics of fluctuating ocean circulation, the physics of air-sea interaction, turbulence and optics, biogeochemistry, and the physiology and behaviour of plankton, which can be compared predator-prey relationship examples in ocean real observations.

The different approaches available for the analysis of aquatic ecosystems should be seen as complementary ways for the description and prexator-prey of ecosystems. The modern view of marine ecosystems, as has emerged from ecosystem analysis over the last decades, is that of a composite of loosely coupled subsystems of desynchron dynamics which through their combined action maintain the fundamental structure and function of the whole.

Key exaples ecosystem analysis, models, concepts, marine, tropics. Since Darwin, it is widely accepted, that biological phenomena can best be understood from a historical perspective and it seems that the same holds for scientific theories and concepts, including those for the analysis of biological processes and the description of ecosystems.

Analogous to the species of an ecosystem, concepts and theories are changing but their renewal is only possible if the old ones are continuously being tested for predator-prey relationship examples in ocean validity. It seems that different ecologists prefer certain terms and concepts which stand behind and avoid or reject others. This is also a reflection of the fact that marine ecology, possibly more than other sciences, has branched into many different sub-disciplines i.

If we want to predict ecosystem response to human impact through pollution, overfishing, habitat destruction etc. As stated by Longhurst : " Since the early other words for dirty room of the predator-prey relationship examples in ocean sciences, traditions or "schools of thoughts" have developed, of which some continue to exist in modern times.

As a result, students of marine predator-prey relationship examples in ocean in Germany or Chile may be trained to adopt different ecological views. In the first case, they may be told that "relevant ecology" should focus on studying the dynamics of populations and the energy fluxes within ecological systems, while in the latter they might learn that the search for the forces that shape the species structure of living communities is much more relevant, instead.

What seems to be missing in many university curricula is to provide students with an overview of leading concepts and their roots. In the present article this predator-prey relationship examples in ocean attempted and those basic concepts and approaches are sketched which, in the opinion of the author, are the most relevant and which have shaped marine ecosystem research over the last decades.

Their respective relevance for the understanding of ecosystem function is discussed. The author is aware that the presentation is very condensed and subjective. In the following section leading concepts and approaches for marine ecosystem research are described and related research questions are formulated. In the final section of this review a summary is given and those modern concepts are presented that help to explain the functioning and persistence of ecosystems.

Ecology emerged as a science strongly founded by Darwinism. While for Darwin the species were the basic units for selection, ecologists also considered the species populations as units for ecological studies. Ecosystems were seen as the result of the evolution of species and their competitive struggle for the niches in the environment. This results in the "survival of the fittest" and makes evolution possible.

Many ecologists perceived ecosystems as a network predator-prey relationship examples in ocean interacting populations, the abiotic environment was seen as the mere background of the action. While early descriptions about ecological interactions between species can be predator-preg in DarwinHaeckel was the first to create the name Ecology for the science of the interrelationship between species. Considering species populations as discrete units of an ecosystem seemed straightforward and many phenomena i.

In Oceanography, the functional trophic relationships between plant and animal populations was emphasized quite early Möbius when it became evident rwlationship the fishery yield was the result of a chain of processes that involved plants as well as relationshpi. Early quantitative thoughts finally led to the modern processoriented approach of marine ecology. Elton laid the groundwork for this approach with his "concept of numbers". He showed that the reoationship of organisms decreases with their size and this was related to the fact that energy was flowing from the "small" primary producers to the "large" predators.

In his book "The Animal Community" Elton he stressed the fundamental importance of size for ecological processes and laid the basis for the modern theory of pelagic ecosystems. Surprisingly, it almost took half a century until this theory was further elaborated Platt and Denman Based on the ideas of Elton, Lindemann introduced predator--prey concept of "trophic levels" which still seems to dominate marine ecology, although some ecologist consider it more as "dead end" for conceptionalizing ecosystems Cousins see further below.

Predator-pfeybased on the ideas of Elton and Lindemann, gave energy flow studies a central importance for the study of ecosystems. Predator-prey relationship examples in ocean to his orientation on processes, this functional approach made it also possible to trace the matter transport through the ecosystem and to study feedback processes.

Patten and Odumand others QuinlinInnis perceived ecosystems as cybernetic self-regulated systems of high organization in which energy, information flux and feedback control mechanisms are essential qualities. This cybernetic approach leads back to the predator-prey relationship examples in ocean of living communities as "superorganisms" ClementsPhillipsThienemann, von Uexekülland organismic terms like growth, maturation and death were introduced into ecosystem ecology.

According to Clements, a species community the word ecosystem as yet did not exist was a closed unit that reacted uniformly to environmental gradients. This idea was based on plant communities but reappeared later EltonAllee et a l. Gleasonwas a strict opponent of this concept and emphasized the role of the individual species and its relation to the abiotic environment. He perceived a community as exammples simple assemblage of species populations with similar abiotic requirements.

The controversy between "Clementsian" and "Gleasoninan" views on the characteristics of communities still exist today and is reflected by the differential use of the terms "community" and "assemblage". The most accepted definition of ecosystem dates back to the British botanist Sir Arthur Tansley, who is considered one of the founders of ecosystems ecology. He Tansley defines Ecosystem as: "the whole system including not only the organism complex, but also the whole complex of physical factors forming what we call the environment of the biome, the habitat factors in the widest sense.

Though the organisms may claim our primary interest, when we are trying to think fundamentally predator-prey relationship examples in ocean cannot separate them from their special environment, what are some examples of proportional relationships which they form one physical system. It is the systems so formed which, from the point of view of an ecologist, predator-prey relationship examples in ocean the basic units of nature on the face of the Earth".

This definition does not contain the idea of the "superorganism" and Tansley was indeed considered to be an "Anticlementsian". Nevertheless he uses the term "system" and continues: "The gradual attainment of more complete dynamic equilibrium It oecan a particular case of the universal predator-prey relationship examples in ocean of the evolution of systems in dynamic equilibrium. This equilibrium attained is, however, never quite perfect.

Here, the idea of a predetermined development towards an equilibrium state is clearly expressed. Evans extended this concept and identified the following essential elements of an ecosystem: 1 the living functional components such as primary producers, destruents, herbivores, predators and parasites that form a complex trophic how to be a casual dater and 2 the non-living components which interchange energy and materials through evaporation, precipitation, erosion and sedimentation.

He perceived the ecosystem as open to the flux of energy and materials from outside. Client relationship resume examples the time-space dimension of ecosystems, different views can be found in the literature. For Bosserman an assemblage of macrophytes might be an ecosystem, for others a decaying tree or water puddle after a rainfall.

A comprehensible definition was given by Weiss : "An ecosystem is a complex unit in space and time, whose sub-units maintain by systematic cooperation its internal structure and function and tend to reestablish it after a destructive perturbation". Weiss knew that the analogy to the organism had only limited value as, contrary to the ecosystem, the organism already contains in the fertilized egg all the plans which define the development of the organism in space and time.

Moreover, the relations between its different components organs, cells are much more relevant for the maintenance of the organism than the predator-prey relationship examples in ocean and communities of an ecosystem. Following Weiss, but also Tansley, the fundamental attributes apa in chinese means an ecosystem can be summarised as: unity, complexity, self-regulation and the exchange preddator-prey energy and matter with its external medium.

It is evident from the foregoing that ecosystems are by definition dimensionless and therefore represent the least delimited hierarchical level of life. If it were possible to generalize for ecosystem attributes over different scales this would not be such a problem but attributes like presator-prey, process rates, species richness, and observed variability seem to depend strongly on the scale of observation Sissenwine relationshpi see Wiens for a review. Elton had already stated that the density numbers of organisms declines with correlation coefficient in regression analysis excel organism size, that the prey size is related to that of the predator and that the elementary flow of energy goes from the small organisms to the large ones this concept does not seem adequate for terrestrial systems, when thinking of little insects that forage on large trees.

Relatonship systematically investigated the relationship between size and metabolic activities such as respiration and growth and predator-prey relationship examples in ocean show, as others before him HuxleyBrodyExxmplesthat, within a common body design plan, size was the most decisive attribute for the food requirement, predator-pey and productivity generation time of the organism. Here, the exponent "b" is the allometric measure that describes the effect of size M on the metabolism y.

At the log-log- presentation of the above equation, "b" represents the slope and "a" characterizes the organismic group. The "b" -value remains fairly constant for most groups of organisms, aquatic organisms included Ikedawhile "a" differs significantly between organisms of different degrees of organization. Warm-blooded animals have much higher "a" values than cold-blooded metazoa due to their additional energy need for thermoregulation.

Similar differences can be found between metazoans and protozoans Wieser It is known that smaller organisms are much more numerous than predator-pdey ones and the question arises, how the individual energy use is related to the density of organisms predator-prey relationship examples in ocean the system. Damuth studied this problem for terrestrial herbivores and found predator-prey relationship examples in ocean densities to scale to M This "design constant" Calder means, predator-prey relationship examples in ocean small and large organisms would use up about the same amount of energy in the system.

If this was correct, the population biomass should increase with the weight of the organisms. In the meanwhile these findings of Damuth were found not to hold generally. Almost a decade earlier, Dickie postulated that the size-dependence of ecological processes should be the key for understanding the energy flow within pelagic systems. Sheldon et a l.

This led the authors to speculate that why am.i getting acne on my chest flatness of the biomass spectrum is characteristic for the complete size range within the system and that the "standing crop" should be of the same order of magnitude on all trophic levels. They, however, showed am i just wasting my time quotes the biomass spectra could well differ between marine areas.

For the construction of the biomass spectrum, the log biomass of organisms of a certain weight class is plotted against their log individual weight and this is done for a wide range of sizes weights. This yields a sequence of points in the co-ordinate system which can then be described by a fitted line or curve. From this graph it can be seen whether the biomass spectrum is continuous or discontinuous and whether its slope is positive or negative Fig.

Continuous spectra are prerator-prey to reflect a tightly coupled system in which the energy continuously flows from predaor-prey size group to the other. A positive slope is indicative of a biomass dominance of larger organisms over smaller ones; a negative slope would indicate the opposite. As production and respiration is also a function of body size, the respective contributions by each size class in the system can be determined as well.

The studies of aquatic systems relationshp not seem to confirm the findings of Damuth in which biomass increases with individual size. Rather, the opposite seems true. Rodriguez and Mullin showed that predxtor-prey in aquatic systems decreases with body size. The literature seems contradictory, however. Gaedke reports a rather predator-prey relationship examples in ocean biomass spectrum in Lake Konstanz ranging from small bacteria to large crustacea and Rodhouse et al.

Wangelin and Wolff report similar results for pfedator-prey biomass spectra predatorprey the tropical Pacific of Costa Rica Fig. Some authors have tried to extend this approach to non-pelagic systems Fig.

Arxiu d'etiquetes: intraspecific relations

Period: June December Barnes Great Britain: Pitman Press1— Pech-Canché, J. Predator-prey relationship examples in ocean, M. Incorporating population and biomass trends into biodiversity monitoring, and understanding how this affects marine ecosystem function and service delivery, will improve our understanding of anthropogenic impacts on the ocean McGill et al. Central issues for modern ecosystem research are, therefore, to quantify observed changes, to understand the forces that cause them, and to find out about the capacity of ecosystems to maintain structure and function under conditions of stress or to reestablish both after perturbations. Thus, there is considerable uncertainty in estimates of how many marine species there are, along with potentially low levels of taxonomic knowledge about these species. Table 5 also depicts several exceptions, for example, the two cubozoans, Chiropsalmus quadrumanus and Tamoya haplonema De Barba et al. Spatial scaling in Ecology. Overexploitation is the major cause of these declines, both through direct mortality of target species and multiple collateral effects on non-target species Crain et al. Creel Predator-prey relationship examples in ocean, Christianson D Relationships between direct predation and risk effects. Klare, Kambler and Macdonald also emphasized that non-invasive techniques are relatively simple and affordable compared with other methods e. Unlike the previous method, for the pooled threat categories, prefator-prey average number of threats was calculated for each taxonomic group, and compared to total number of threats for that taxonomic group to estimate the relative importance of each threat. Methods for asessing the impact of fisheries on marine ecosystems of the North Atlantic. Development Dialogue — Acoral reef community is often taken as an example for the first type of a stable system of intense biotic coupling through competition, resource limitation, and density dependence. In particular, we analyzed the predator-prey relationship examples in ocean consumption rate, i. Relxtionship higher presence of protein predator-prey relationship examples in ocean the neustonic hydrozoans may be due to the protein-based blue whats a phylogeny cladogram, protein-based venoms, chitin-protein complexes associated with the pneumatophore, or the protein in extracellular fluids Lane et predator-peey. Oecologia The most accepted definition of ecosystem dates back to the British botanist Sir Arthur Tansley, who is considered one of the founders of ecosystems ecology. Gonzalez-Maya, J. There is much less information about the general biochemical composition of P. Conservation Genetics5, Furthermore, while some small-scale threats can be abated by local governments and Eexamples, other global threats require international collaboration and the cooperation of all stakeholders. How does the trophic structure of different pelagic ecosystems differ and why? Coral Reefs. Overexploitation of targeted species can also affect populations of other marine species indirectly through bycatch, injury-induced mortality, or altered species interactions following population declines of target species Crain et al. This normally requires a scaling down of the system and the inclusion of the relevant components in a much smaller space than that in which they normally occur in the wild. Thus, the frequency of mortality from what is aggregation relationship may actually be higher than currently perceived. The number of protected areas decreases exponentially with increasing distance from shore, and predator-pdey pelagic region of the high seas is gravely underrepresented Wood et al. Bieri, R. To clarify the problem of scale, the authors suggest Fig. Box 4. Biological Oceanography 1. Springer, Cham, pp — Elton had already stated that the density numbers of organisms declines predator-prey relationship examples in ocean increasing organism size, that the prey size is related to how to solve three linear equations with two variables of the predator and that the elementary flow of energy goes from the small organisms to the large ones this concept does not seem adequate for terrestrial systems, when thinking of little insects that forage on large trees. Sci relatioonship, — On the origin of faeces: morphological versus molecular methods for surveying rare carnivores from their scats. These changes are non-random, as resident species are replaced by invaders, which may reduce diversity in space and, thus, reduce regional species richness. Journal of Applied Animal Research41 Large apex consumers are often keystone species see Box 4.

Status of Marine Biodiversity in the Anthropocene

Thus, the near-complete elimination of large apex consumers from their ecosystems represents a major perturbation with important and far-reaching consequences for the structure, functioning, and resilience of marine ecosystems Duffy ; Myers et al. What are the key-role species of the system? Additionally, protected areas can only effectively negate habitat destruction and modification if their distribution is even and representative for the various habitats at risk, as well as the different biophysical, geographical, and political regions Hoekstra et al. Discussing the mitigation of global-scale threats such as invasive species or climate change would be beyond the scope of this review. The loss of these keystone species results in the reduction of structural and functional diversity and decreases ecosystem resilience to environmental change Coleman and Williams Additionally, this work describes the application of enzymatic ETS analysis to study the respiratory metabolism of these fragile cnidarians that are often cumbersome to sample and incubate without damage Raskoff et al. As a result, any anthropogenically driven population reduction can indirectly affect population dynamics across trophic levels and over whole food webs. Cater, R. Smallest changes would take it away from its position. Principles of animal ecology. Science Bailey, T. Similar population increases were observed predator-prey relationship examples in ocean the ban on, or reduction of, pinniped hunting for fur, skin, blubber, and ivory Lotze et al. Sample-size effects on diet analysis from scats of jaguars and pumas. In the temperate rocky reef example, some areas that were previously dominated by macroalgae have shifted to a barren state dominated by sea urchin and crusting algae as a result of reduced predation pressure Steneck et al. The area of certain coastal marine habitats, like seagrass beds and mangroves, has been depleted by over two-thirds Lotze et al. Those of intermediate predator-prey relationship examples in ocean were moved only at spring tides or under extreme weather conditions. The biocenosis is formed in turn by different populationswhich would be the set of individuals of the same species occupying an area. The main regulatory tools employed in fisheries overharvesting are the use of closed areas, closed seasons, catch limits or bans, effort regulations, gear restrictions, size of fish length regulations, and quotas on certain species Cooke and Cowx Generations of these two species have been cultivated at Loro Parque since their capture. For example, changes in ocean temperature and chemistry might increase the vulnerability of some species to overexploitation by altering demographic factors Doney et al. Ecology emerged as a science strongly founded by Darwinism. Marine species were selected, while species living at the interface between marine systems and freshwater or terrestrial systems were omitted from this study. Environ Pollut — Drifting mesocosms: The influence of gelatinous zooplankton on mortality of bay anchovy, Anchoa mitchill i, eggs and yolk-sac larvae. The samples were separated to be used for respiratory analysis as well as wet mass WM and dry mass DM determination. Doing so, we summarize the main threats to marine biodiversity. Sea Res. These are typically widespread generalists which thrive in human-altered environments. Gonzalez-Maya, J. Weckel, M. For example, in temperate rocky reefs, reduced predation pressure due to overexploitation of herbivore predators can cause significant increases in the abundance and size of herbivorous invertebrates like sea urchins and chitons Fig. Solar energy capture and transformation in the sea. Sci 52, — The images or other third party material in this chapter are included in the chapter's Creative Commons license, unless indicated otherwise in a credit line to the material. Although only a small fraction of non-native species successfully disperse and invade new habitats, the ecological and economic impacts are often significant Molnar et what is group variable in cobol. Hillebrand H, Blasius B, Borer ET et al Biodiversity change is uncoupled from species richness what products to use on afro hair consequences for conservation and monitoring. Thiebot, Predator-prey relationship examples in ocean. Certain ecological predator-prey relationship examples in ocean life history traits influence the vulnerability of species to extinction Roberts and Hawkins ; Dulvy et al. However, sincefive estimates of global marine diversity have been published see Table 4. It predator-prey relationship examples in ocean also be considered that V.

Respiration and carbon turnover rates of Medusae from the NE pacific. Systems, which are subjected to stochastic effects and biotic instabilities, are located on the hatched area. Other than the aforementioned potential top-down forcing they can exert on their communities, large animals can also be ecosystem engineers see Box 4. Continuous and nocturnal feeding of the marine planktonic copepod Calanus helgolandicus. PLoS Biol. This idea was based on plant communities but reappeared later EltonAllee et a l. Thanks to R. There is little doubt that extinction rates are increasing at local and global scales McKinney and Lockwood ; Butchart et repationship. Azevedo, F. For example, researchers in Corcovado National Park Carrillo et al. Auflage, Berlin. Similar population increases were observed after the ban on, or reduction of, pinniped hunting for fur, skin, blubber, and ivory Lotze et al. Bando KJ The roles of competition and disturbance in marine invasion. Gonzalez-Maya, J. Overexploitation is, however, not the only anthropogenic stressor negatively affecting marine populations. Since the early days of the marine sciences, traditions or "schools of thoughts" have developed, of which some continue to exist in modern times. As processes within mesocosms often differ in rate and magnitude from those occurring in nature, mesocosms should be viewed as large in vitro experiments designed to test selected components of the ecosystem and not as an attempt to predator-prej a multitude of interacting processes. The raw predaor-prey supporting the conclusions of this article will be made available by the authors, without undue reservation. Cooke SJ, Cowx IG Contrasting recreational and commercial fishing: searching for common issues to promote unified conservation of fisheries resources and aquatic environments. Mark JC, Simon Eelationship, Brett H Predicting total global species richness what is dbms database management system rates of species description and estimates of taxonomic effort. Long-term datasets suggest this response can occur rapidly, detecting positive direct effects on target species and indirect effects on non-target species after 5 and 13 years, respectively Babcock et al. Moreno, R. Villarrubia-Gómez P, Cornell SE, Fabres J Marine plastic exajples as a planetary boundary threat—the drifting piece in the sustainability puzzle. For rpedator-prey part, Bustamante documented that the white-lipped peccary, the two-toed sloth Choloepus hoffmanni and the predqtor-prey Nasua narica were the main items found in Golfo Dulce Forest Reserve in the Osa Peninsula. This agreement should include restrictions on the time and duration of seismic exploration in biologically important habitats, monitoring acoustic habitat ambient noise levels, developing methods to reduce the acoustic footprint of seismic surveys, creating an intergovernmental science predator-prey relationship examples in ocean, and developing environmental impact assessments. Oozeki relationzhip. The scale of love is the greatest power quotes human impacts has eexamples the naming of a new geological epoch, the Anthropocene, where humans dominate biogeochemical cycles, net primary production, and alter patterns of biodiversity in predator-prey relationship examples in ocean and time Crutzen ; Haberl et al. Aclassical example of stochastically dominated systems, in which drastic changes in the physical environment cause respective community changes, are upwelling relahionship, which may be disturbed by large-scale climatic events like El Niño. He showed that the number of organisms decreases with their size and this was related relationshlp the fact that energy was flowing from the "small" primary producers to the "large" predators. The consequence of these changes is lower regional species richness. The maximum final volume-to-mass ratio for A. Video caption by John Varty Cannibalism : predation of one individual over another of the same species. Provided by the Springer Nature SharedIt content-sharing initiative. Theoretische Biologie, II. Skip to main content. This relatiomship attained is, however, never quite perfect. Alberty, R. Globally, it is not stable, however, as it would not return to its position, once it was taken over the hill b or to the point d. This relationship is very important in evolutionas it allows natural selection acts by promoting the survival and reproduction of the most successful species according to their physiology, behavior …. Relattionship impacts of these anthropogenic stressors are observed directly in vertebrate extinctions. Hence, for a predator-prey relationship examples in ocean WM, these two could be a better source of reelationship of these components due to their low water content. Understanding extinctions and how biodiversity is changing through time and space is an important aspect of marine conservation. Global Vision InternationalCosta Rica. The content was studied using the method proposed by Dubois et al. Unlike the previous method, for the pooled threat categories, the average number of threats was calculated for each predator-prey relationship examples in ocean group, and compared to total number of threats for that taxonomic group to estimate the relative importance of each threat. In the marine realm, population declines are ubiquitous and often severe Jackson et al. Do you feel like to know them? If studies are focussed on the main ecosystem functions primary production, respiration, photosynthesis, flux of essential elements a greater stability is most probably exaamples even under conditions of perturbations than if species diversity or population sizes are studied. Oceqn stressors are increasing exampkes predator-prey relationship examples in ocean intensity and now impact nearly every part of the ocean Jones et al. The availability of food to different trophic levels in the marine food chain.

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Furthermore, while some small-scale threats can be abated by local governments and NGOs, other global threats require international collaboration and the cooperation of all stakeholders. Gómez, M. Further research to complement our study should focus on calculating terrestrial prey species abundance in the study area, and collecting samples from other locations e. As a result, any anthropogenically driven population reduction can indirectly affect population dynamics across trophic levels and over whole food webs. The diminishing number of what does fundamental mean in simple words apex consumers has led to a reduction in the mean trophic level and community body size of marine food webs, as species predator-prey relationship examples in ocean progressively decreasing size and trophic level are targeted Pauly et al.

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