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Simonetta Fraschetti Giuseppe Guarnieri Stanislao Bevilacqua Antonio Terlizzi Joachim Claudet Giovanni Fulvio Russo Ferdinando Boero 《水产资源保护:海洋与淡水生态系统》2011,21(3):299-306
- 1. The relentless increase in both human activities and exploitation of marine resources is a threat to marine habitats and species.
- 2. For marine systems, several protection initiatives have been outlined over the past decade to significantly reduce the current rate of biodiversity loss at global, regional, and national levels, and to establish representative networks of marine protected areas with the aim of protecting 10–30% of marine habitats.
- 3. Reliable estimates of the total area occupied by each habitat are crucial to set adequate protection initiatives. Habitat mapping requires a sound habitat classification. Many classification schemes have been developed in different areas of the world, sometimes based on questionable criteria.
- 4. A critical analysis of the most recent marine habitat classification list produced for the Mediterranean Sea from the Regional Activity Centre for Specially Protected Areas (RAC/SPA) showed that (i) 39% of habitats and associated species considered in the list are scarcely covered by scientific knowledge from Web‐based resources; (ii) 62% of the species/genera included in the list are primary producers; (iii) quantitative information about the geographical distribution of selected habitats and associated species is scant; and (iv) when available, information is largely unbalanced and biased towards the shallow western Mediterranean Sea.
- 5. Improved inventories of marine habitats are needed to support accurate and consistent mapping activities. The combination of large‐scale mapping and sound habitat classifications will allow better estimates of biodiversity distribution, to reverse regional/global habitat loss rates through the achievement of conservation targets and deadlines that, for the moment, are systematically not met. Copyright © 2011 John Wiley & Sons, Ltd.
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- 1. Fishing is one of the most widespread anthropogenic impacts on marine ecosystems. In recent times, the development of measurable metrics of the resultant ecosystem effects, has become an important aspect of fisheries management. Ecosystem models are often advocated as tools for the evaluation of system effects, but the extent to which models are able to make meaningful predictions, has not yet been fully addressed.
- 2. In order to assess the suitability of models, to evaluate ecosystem effects of fisheries, the direct and indirect effects were catalogued.
- 3. From the literature, 33 applications of marine ecosystem models were identified for analysis of their ability to fully assess these catalogued effects. Analysis was possible for only 24 of the models due to poor documentation of the other 9.
- 4. Each model was examined for their inclusion of nine functional groups, deemed essential for the assessment of impacts of fishing on the whole ecosystem (e.g. detritus, marine mammals). The models were also assessed for their inclusion of several additional factors, either fundamental in the regulation of marine ecosystems (e.g. environmental forcing), or important in the classification of their role as a predictor of changes in ecological processes (e.g. simulation, spatial properties).
- 5. No model formulation provided coverage in all the areas necessary to cover the identified effects of fisheries. Eight models provided good coverage, nutrient dynamics and benthos were the least well represented aspects of the ecosystem.
- 6. The ECOPATH with Ecosim family of models, the European Regional Seas Ecosystem Model (ERSEM) and the Anderson & Ursin multispecies extension to the Beverton & Holt model all seem likely to yield good insights.
- 7. In further developing these models, however, consideration must be given to explicitly incorporate spatial factors and extrinsic forcing functions, such as climate.
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Mary E Hunsicker Timothy E Essington Reg Watson Ussif R Sumaila 《Fish and Fisheries》2010,11(4):421-438
Cephalopods are a key component of marine food webs, providing sustenance for myriad marine species. Cephalopods are also of increasing economic importance as evidenced by the rapid rise in their global landings over recent decades. If fisheries continue on this trajectory, conflicts may transpire among cephalopod and finfish fisheries, particularly in ecosystems where cephalopods are highly valuable both directly as a landed commodity and indirectly as prey for other harvested species. We provide the first measure of the ecosystem services that cephalopods contribute to fisheries in 28 marine ecosystems, both as a commodity and an ecological support service. We also evaluate how current demands on cephalopods compare to mid‐20th century conditions. We find that cephalopod contributions to fisheries vary widely, but are substantial in many ecosystems. Commodity and supportive services provided by cephalopods contributed as much as 55% of fishery landings (tonnes) and 70% of landed values ($USD). The contribution of cephalopods as a commodity was generally greatest in the coastal ecosystems, whereas their contribution as a supportive service was highest in open ocean systems. Further, the commodity and supportive services provided by cephalopods to fisheries landings increased in most of the coastal ecosystems between the mid‐20th century (years 1960–70) and contemporary periods (years 1990–2004), indicating the rising demand for cephalopods. Current demands have no historical precedent and ecosystems in which cephalopods are highly exploited as a targeted resource and as an ecological support service should be further evaluated to prevent the unsustainable development of marine fisheries within them. 相似文献
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China is the world’s biggest fishing nation and a major player in the global seafood trade. Its fisheries development can decisively influence the global seafood trade, food security and marine conservation. In recent years, significant changes have taken place in China’s fisheries management priorities, policies and regulations. In this paper, we review the evolving fisheries management practices in China to delineate changes in the management policies, methods and their performances from 1949 to 2019. We determined that the following issues impede the development, implementation and enforcement of fisheries policies and regulations, namely the large size of the fishing fleet, large and poorly organized fisheries population, the “hidden” fishing capacity, uniform management approaches that sometimes fail to account for local conditions, lack of clearly defined and allocated fishing rights, limited data quality and availability, insufficient fisheries monitoring programmes, absence of a robust scientific input framework and insufficient stakeholder involvement. Combining those problems with China’s current management initiatives, we propose recommendations for China’s future fisheries reforms. We hope this paper can inform China’s marine fisheries policies and provide valuable references for further researches related to China’s sustainable fisheries management. 相似文献
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‘Fishermen’ and the gender‐neutral ‘fishers’ are the most common terms used to describe people who fish in the English language. However, there is a considerable debate as to which term is most appropriate. In academic journals, usage of ‘fishers’ for people who fish began in the 1960s and increased over time, until in 2013 and 2014 ‘fishers’ first exceeded usage of ‘fishermen’, despite being labelled ‘archaic’ in the Oxford English Dictionary. In journal searches ‘fishermen’ unambiguously referred to people who fish, but ‘fishers’ also referred to R.A. Fisher's statistical tests (22%), the mammal, Pekania pennanti (5%), and other terms. Journal policies have played a role in the shift to ‘fishers’: e.g. Conservation Biology requires the use of ‘fishers’ while Fishery Bulletin requires ‘fishermen’. Partly as a result, in academia there are disciplinary and geographic variations, with greatest usage of ‘fishers’ in the field of conservation biology and in Australia. Surprisingly, word choice did not differ by the gender of the lead author. Many other languages also have gender‐neutral terms for people who fish (e.g. Austronesian and Turkic languages), yet the word is still assumed to refer to men. While the gender‐neutral term ‘fisher’ is more inclusive it is far from universally accepted, particularly by women and men in the North American fishing industry. The current shift towards the more inclusive term ‘fishers’ highlights the increasing disciplinary diversity within fisheries science, particularly in terms of gender. 相似文献
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Alain Pasquet Emilie Realis‐Doyelle Pascal Fontaine Fabrice Teletchea 《Aquaculture Research》2019,50(7):1824-1833
This study investigated the influence of temperature (4, 8 and 12°C) on development and survival of brown trout (Salmo trutta) fry. The three aims of this study were: (a) to propose a typology of malformations; (b) to compare malformation types between live and dead fry and (c) to establish relationships between temperature and malformation occurrences. It was found 20 single malformations and 39 combinations of two or more malformations. Comparison between dead and live fry at different development stages (hatching, emergence and first food intake) showed that malformations of yolk sac were predominant at hatching and then decreased, while malformations of skeleton or multiple malformations were higher thereafter. All dead fry, and only 14% of live fry were malformed. Dead fry were mainly characterized by yolk sac malformations and multiple malformations whatever the temperature. Live fry showed a higher rate of skeleton malformations at 12°C, and the different types of malformations were equally represented at two other temperatures (4 and 8°C). To conclude, it is suggested that some malformations (yolk sac at hatching, yolk sac associated with skeleton malformations at emergence and skeleton at first food intake or combinations of malformations at all stages)might be lethal as they were founding dead fry and that temperature influences differently the occurrence of malformations. 相似文献
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Lucas dos Santos Rodrigues Maria Grazia Pennino David Conesa Eidi Kikuchi Paul Gerhard Kinas Fabiana Gonçalves Barbosa Luís Gustavo Cardoso 《Fish and Fisheries》2023,24(1):159-175
Ecological niche models (ENMs) and species distribution models (SDMs) have been widely applied to various studies relevant to biogeography, conservation biology, and ecology. These modelling techniques seek to develop spatial maps for projecting, among others past, current, and future species distributions. Born in the field of terrestrial ecology, only in recent years have these models been applied to marine environmental issues, especially to improve the forecasting of the distribution of occurrences and capturing of fishery resources. This study aimed to present through bibliometric analysis the characteristics of articles related to the use of ENMs and SDMs in marine fishery resources considering three main points: (1) state of the art: number of articles over the years, journals, countries, collaborations, and focus of research; (2) characteristics linked to fishery resources: marine biogeographic realms, taxonomic groups, life phases, oceanographic zones, and behaviours; (3) characteristics linked to methods: type of method, type of biological and, environmental data. We provide a list of 378 articles (derived from 930 screened ones), the results, and a discussion of our findings, which represent a baseline for the current status (strengths, limits, and gaps) of the interface between ENMs/SDMs and fishery resources. 相似文献
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Have we neglected the societal importance of sand dunes? An ecosystem services perspective 总被引：1，自引：0，他引：1
- 1. Coastal sand dunes are widespread worldwide, including around the coasts of the British Isles and Europe, providing a wide range of functions some of which are recognized for their socio‐economic benefits.
- 2. In some localities, their contribution to coastal defence and to tourism and regional character have been acknowledged in local plans, but this is far from ubiquitous.
- 3. A rapid assessment was undertaken of the range of ecosystem services provided by coastal sand dune systems, using the Millennium Ecosystem Assessment ecosystem services classification augmented with habitat‐ and locally‐appropriate additions.
- 4. Sand dunes were shown to provide a wide range of provisioning, regulatory, cultural and supporting services, many of which remain substantially overlooked.
- 5. Although the importance of coastal sand dune for a diversity of characteristic and often rare organisms from a variety of taxa has been addressed, many of the broader ecosystem services that these habitats provide to society have been overlooked. This suggests that coastal sand dune systems are neglected ecosystems of significant and often under‐appreciated societal value. Copyright © 2010 John Wiley & Sons, Ltd.
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Benni Winding Hansen Giorgia Ciappini Anders Malmendal Thomas Allan Rayner 《Aquaculture Research》2022,53(1):178-190
The copepod Apocyclops royi tolerates very low salinity while being highly capable of synthesizing n-3 fatty acids based on PUFA-poor diets. The feasibility of culturing A. royi in freshwater fed with baker's yeast was evaluated. The copepods were adjusted for 8 days by decreasing stepwise from salinity 20 to freshwater diluting with deionized water. Initially, the cultures exhibited adequate survival and reproduction. However, after 10 days in freshwater, they stopped reproducing presumably due to the lack of vital ions in the medium. Therefore, before continuing the freshwater cultures, we tested the survival of a batch of salinity 1 pre-acclimated adults and copepodites in various types of freshwater: deionized, bottled ‘mineral’ and tap water for 48 h. All copepods died in deionized water, but a significantly higher survival, 29% ± 11%, was found in mineral water versus 11% ± 8% in tap water. Hence, we continued culturing the copepods in freshwater using ‘Maglekilde spring’ water as diluter. The copepods regained and kept reproducing until day 71 where the experiment was terminated. After a 48 h freshwater versus salinity 20 exposure, nauplii survival was significantly less in freshwater 25 ± 12 versus 79 ± 20 (±STD) at salinity 20 but not different in mean body length. For the first time, we conducted NMR metabolomics revealing a large decrease in glycine betaine and a large increase in lactate in the copepods when challenged by freshwater versus salinity 20. There is obviously a ‘price to pay’ when culturing not only the copepods in freshwater, but also perspectives in developing a ‘universal’ A. royi live-feed product. 相似文献
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AndersAksnes JanPettersen 《海洋水产研究》2001,22(4):64-70
IntroductionThe objective of the project was to deal with polluting problems connected with the feed quality andaquaculture.‘Feed quality’is defined by the quality of the feed ingredients with reference to the biologicaloutcome in the feeding period with special emphasis on the feed digestibility.Pollution is caused by the uneat-en feed and the undigested feed excreted with the faeces.These are detected in the surroundings (e.g.the ma-rine environment) and occur as organic pollution.The exp… 相似文献
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Nicole Pacini Ambrosius Josef Martin Dörr Antonia Concetta Elia Melissa Scoparo Maria Cesarina Abete Marino Prearo 《Fish physiology and biochemistry》2014,40(5):1609-1619
In 2007, renal failure and death in pets were linked to pet food containing both melamine (MEL) and cyanuric acid (CYA). In mammals and fish, the co-administration of MEL and CYA causes renal crystal formation. Moreover, little is known about the process of crystal removal in fish. The aim of this study was to evaluate the formation of MEL–cyanurate crystals in kidney of rainbow trout (Oncorhynchus mykiss) fed combined MEL and CYA diets for 10 weeks at 250, 500 and 1,000 mg/kg in feed (equivalent to 2.5, 5, 10 mg/kg body weight of trout fed 1 % body weight per day). During the exposure trial and throughout a withdrawal period, prooxidant effects of MEL and CYA were evaluated on oxidative stress markers such as catalase, glutathione S-transferase and malondialdehyde. Crystal formation was dose and time dependent, and after six withdrawal weeks, crystals persisted in kidney of trout treated the highest triazine dose. Catalase and glutathione S-transferase activity in kidney of trout exposed to both triazines for 10 weeks indicated that MEL (with or without CYA) can exert a higher prooxidant effect than CYA dispensed singly. Although the enzymes activity increase appears to be reverted after two MEL withdrawal weeks, persistence of crystals may lead to severe damage in renal cells of fish. 相似文献
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Dorothy J. Dankel Nikki Jacobson Dan Georgianna Steven X. Cadrin 《Fisheries Research》2009,100(3):240-247
Georges Bank haddock is a recently recovered fish stock in the New England groundfish fishery. Due to federal constraints under the Magnuson–Steven Act, however, this stock cannot be optimally exploited due to the bycatch of other critical species in the New England groundfishery such as cod and yellowtail flounder which are overfished. The Ruhle trawl and Separator trawl are examples of recent advances in gear technology that have been shown to significantly increase haddock to bycatch ratios. This study models the groundfish fishery through a mixed-stock yield model which incorporates technological interactions. We also develop a socio-economic model that quantifies the amount of employment and producer surplus associated with three trawl types. Our results explore policy situations regarding the use of the new trawls. By bridging the biological and socio-economic models, we are able to view the fishery as a system that more accurately represents stakeholder views. Our model shows that each trawl, when used exclusively, produces different optimum strategies and therefore an optimum management strategy would most likely include a combination of trawl types. Our results also support the logic of using modified trawls for haddock fishing trips in which bycatch is strictly regulated (“B days”) as the Ruhle trawl is able to maintain 80% of catches caught by a conventional trawl while reducing bycatch up to over 60%. This paper is a first step towards an aid for policy makers to examine fishery gear trade-offs and the resulting biological and socio-economic consequences of different management actions within the constraints of the Magnuson–Stevens Act. 相似文献
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Anna Hellqvist Monika Schmitz Christina Lindberg Per-Erik Olsson Bertil Borg 《Fish physiology and biochemistry》2001,25(4):311-317
The mRNA expression of the LH- and FSH- subunits were measured in nesting and post-breeding male three-spined sticklebacks, Gasterosteus aculetaus, as well as in castrated and sham-operated nesting males. Furthermore, expression of an androgen induced kidney protein, spiggin, and 11-ketotestosterone (11KT) levels, were measured in the castrated and sham-operated males. Nesting males had significantly higher levels of both LH- and FSH- mRNA expression compared to post-breeding males. Furthermore, sham-operated males had significantly higher levels of LH- mRNA and spiggin mRNA expression than the castrated fish. Expression of FSH-, on the other hand, did not differ between castrated and sham-operated males. There were strong positive individual correlations between circulating levels of 11KT on the one hand and expressions of LH- and spiggin mRNA, whereas the correlation between 11KT levels and FSH- mRNA was weak. The negative effect of castration on -LH mRNA indicates that gonadal hormones stimulate this expression, whereas this was not the case for -FSH. The observed decline in -LH expression after the end of the breeding season may be the result of cessation of the gonadal stimulation of the pituitary. On the other hand, it is not likely that this can explain the decline in FSH- expression. 相似文献
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