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11.
Reg A Watson Bridget S Green Sean R Tracey Anna Farmery Tony J Pitcher 《Fish and Fisheries》2016,17(3):585-595
Knowing where and how seafood is caught or farmed is central to empowering consumers, and the importers that supply them, with informed choices. Given the wide‐ranging, complex and at times commercially sensitive nature of global seafood trade, it can prove very challenging to link imported seafood with information about its provenance. The databases involved are incomplete, at times vague and not harmonized. Here, we present a first attempt to link all global seafood imports through a virtual marketplace to exports and map their origins. Considerable work remains to ground‐truth the specific origins of all seafood commodities. We illustrate the flow of seafood and its evolution since the 1970s when supporting records began. This work allows the impact of fishing or marine farming to be associated with seafood imports. 相似文献
12.
R. S. Pitcher D. W. Way B. M. Savory 《The Journal of Horticultural Science and Biotechnology》2013,88(4):379-396
The characteristics of the disorders here termed "specific replant diseases”' are briefly described and an account is given of a three-year series of field studies. The test plants used were of apple (Malus pumila Mill.) and cherry (Prunus avium L.), each planted in cherry and apple land; the fumigants chloropicrin, chlorobromopropene, dazomet, dichloropropane-dichloro- propene, methyl bromide and methyl isothiocyanate, were applied at various rates prior to planting. All effected some improvement in plant growth, but chloropicrin proved outstanding, the growth of cherries being increased up to threefold by rates as low as 10 gallons per acre. Results obtained with apple were less clear-cut, probably because apple replant disease proved to be of little importance on the experimental fields used. Although these were primarily fumigant-screening trials, it can be deduced that tylenchid plant-parasitic nematodes do not cause either apple or cherry specific replant diseases. 相似文献
13.
Paralytic shellfish poisoning (PSP), due to saxitoxin and related compounds, typically results from the consumption of filter-feeding molluscan shellfish that concentrate toxins from marine dinoflagellates. In addition to these microalgal sources, saxitoxin and related compounds, referred to in this review as STXs, are also produced in freshwater cyanobacteria and have been associated with calcareous red macroalgae. STXs are transferred and bioaccumulate throughout aquatic food webs, and can be vectored to terrestrial biota, including humans. Fisheries closures and human intoxications due to STXs have been documented in several non-traditional (i.e. non-filter-feeding) vectors. These include, but are not limited to, marine gastropods, both carnivorous and grazing, crustacea, and fish that acquire STXs through toxin transfer. Often due to spatial, temporal, or a species disconnection from the primary source of STXs (bloom forming dinoflagellates), monitoring and management of such non-traditional PSP vectors has been challenging. A brief literature review is provided for filter feeding (traditional) and non-filter feeding (non-traditional) vectors of STXs with specific reference to human effects. We include several case studies pertaining to management actions to prevent PSP, as well as food poisoning incidents from STX(s) accumulation in non-traditional PSP vectors. 相似文献
14.
Petrarch's Principle, named here, is to know things unseen, yet to ignore things seen. We apply the principle to the debate over the appropriate role and utility of human-made reefs (HMRs) in fishery and ecosystem management by reviewing four linked issues that were discussed at the recent 7th International Conference on Artificial Reefs and Related Aquatic Habitats. First, deploying protected HMRs can help to mitigate the depletion of fishery stocks through overharvest and habitat degradation. Secondly, to achieve this objective effectively, it is essential that HMRs are protected as no-take areas, and that, thirdly, HMRs are large, well-planned, evaluated and monitored. Finally, ecosystem modelling and adaptive management responses are necessary to forecast and manage the benefits of HMRs. Moreover, uncertainty about the resolution of the well-rehearsed attraction/production debate may be resolved by ensuring that HMRs are managed as protected no-take areas. And to ensure an unbiased attitude that will aid the clarification of consequences, costs and benefits, we propose a change in terminology, from artificial reefs to human-made reefs. 相似文献
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Ecosystem goals can reinvigorate fisheries management, help dispute resolution and encourage public support 总被引:4,自引:0,他引:4
Tony J Pitcher 《Fish and Fisheries》2000,1(1):99-103
This paper argues that if rebuilding of ecosystems is adopted as the goal for fisheries management, recent disputes over political interference in the scientific process would be reduced in severity through a clarification of objectives and procedures. The use of an ecosystem approach enables alternative end states of current harvesting policy to be evaluated more objectively. Moreover, support from the general public for fisheries policy is likely to be greater when they are given a clear and important role to play as sentinels reporting upon the status of a wide range of organisms in aquatic ecosystems. 相似文献
19.
Brissett NC Pitcher RS Juarez R Picher AJ Green AJ Dafforn TR Fox GC Blanco L Doherty AJ 《Science (New York, N.Y.)》2007,318(5849):456-459
Nonhomologous end joining (NHEJ) is a critical DNA double-strand break (DSB) repair pathway required to maintain genome stability. Many prokaryotes possess a minimalist NHEJ apparatus required to repair DSBs during stationary phase, composed of two conserved core proteins, Ku and ligase D (LigD). The crystal structure of Mycobacterium tuberculosis polymerase domain of LigD mediating the synapsis of two noncomplementary DNA ends revealed a variety of interactions, including microhomology base pairing, mismatched and flipped-out bases, and 3' termini forming hairpin-like ends. Biochemical and biophysical studies confirmed that polymerase-induced end synapsis also occurs in solution. We propose that this DNA synaptic structure reflects an intermediate bridging stage of the NHEJ process, before end processing and ligation, with both the polymerase and the DNA sequence playing pivotal roles in determining the sequential order of synapsis and remodeling before end joining. 相似文献
20.
Konrad Dabrowski Stephen Hassard John Quinn Tony J. Pitcher A.M. Flinn 《Aquaculture (Amsterdam, Netherlands)》1980,21(3):213-232
Three experiments were conducted with rainbow trout to determine if Geotrichum candidum GC single cell protein could replace 100, 75 or 50% of fish meal in a pelleted diet. When the fish meal was completely replaced by GC the fish growth was retarded after 3 weeks of the experiment. With the larger fish (individual weight 47–54 g) in the short trial there were significant differences between fish fed the control diet (fish meal) and those fed the 75% substitution of GC diet. The most remarkable differences in fish growth appeared in a 42-day trial with small fish (5 g individual weight) when fish groups fed diets with 0.50 and 75% replacement gave significantly different results (P < 0.05), being 93,9, 46.6 and 34.2% gain, with feed coefficients of 1.49, 2.77 and 3.67, respectively. With large fish fed diets with 0,50 and 75% GC replacement, apparent digestibility of protein was 64.7, 68.2 and 37.5%, but fat digestibility was 79.5, 91.1 and 81.0%, respectively. No significant differences in amounts of free plasma amino acid (PAA) were found between rainbow trout fed diets with 0 or 50% substitution, but there was a marked decrease in PAA in the group fed the diet with 75% GC substitution. Analysis of chosen heavy metals was made on diets, fish and faeces, and Cu in particular was found not to be accumulated in the fish body. 相似文献