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101.
Intraperitoneal injection of turbot with Cd induced the synthesis of a low molecular weight hepatic Cd-binding protein and a 500bp mRNA, which hybridised to a plaice metallothionein (MT) cRNA probe. The Cd-binding protein displayed cross-reactivity in a competitive ELISA with antiserum raised against rainbow trout MT and had the characteristic amino acid composition, metal stoichiometry and spectral characteristics of a Class I MT. Only one isoform was apparent on ion exchange chromatography. Southern blot analysis of DNA cleaved with four restriction enzymes suggested that only a single MT gene is present in turbot.In an established turbot fibroblast cell line, Cd induced MT mRNA and MT levels in a dose and time-dependent manner. MT was also induced by Cu, Hg and Zn but not Pb exposure. Physiological concentrations of glucocorticoids and sex hormones did not induce MT synthesis, although at high concentrations a positive response to corticosterone, dexamethasone, hydrocortisone or progesterone was observedin vitro indicating the possible presence of a functional steroid regulatory element in the fish MT gene.Abbreviations used AMP adenosine monophosphate - CHSE chinook salmon embryo - DMSO dimethyl sulphoxide - HPLC high performance liquid chromatography - KB kenacid blue - MT metallothionein - Mr molecular weight (kDaltons) - NR neutral red - PEG polyethylene glycol - RTH rainbow trout hepatoma - SDS sodium dodecyl sulphate - SSC 0.15M NaCl, 0.015M sodium citrate - TF turbot fibroblast  相似文献   
102.
Abstract  Fish sanctuaries are types of aquatic protected areas common throughout the landlocked country of Lao PDR. The key to their successful implementation in Laos appears to be local support. Therefore, they fit well within the context of community-based fisheries/co-management programmes. Fish sanctuaries are almost always established in deep-water pools, which serve as important dry season refuges for fish. The best-known fish sanctuaries in Laos are known as Fish Conservation Zones (FCZs), and are found in the mainstream Mekong River in Khong district, Champasak province, southern Laos. In Khong, there is increasing evidence that FCZs established by villagers, but with government support, are important places of concentration for various fish species. FCZs can benefit fish stocks, especially relatively sedentary species, but also highly migratory ones. FCZs are not panaceas for solving all the fisheries problems in Laos or the Mekong River Basin, but they represent important management tools that should not be overlooked.  相似文献   
103.
A 4‐week feeding trial was conducted to test the use of marine yeasts purified from seawater and sediments as a dietary source in cultivating a cladoceran, Moina macrocopa, a potential alternative live food for fish larvae. Optimal growth conditions of two yeast strains were obtained for NaCl concentration, pH and temperature. Moina macrocopa was cultivated using different diets: marine yeasts (Debaryomyces hansenii Yeast‐14 and Candida austromarina Yeast‐16) and a commercial diet (Erythrobacter sp. Sπ‐I). The essential amino acids of both the yeast strains were nearly as great as those in M. microcopa. Further, the yeast‐fed M. macrocopa had essential amino acid profiles similar to the documented values for rotifers and Artemia enriched in microalgae and commercial diets. Erythrobacter sp. Sπ‐I lacked n‐3 polyunsaturated fatty acids, 20:5n‐3 and 22:6n‐3, which were also low but detected in both yeasts. An increase in the 20:5n‐3 [eicosapentaenoic acid (EPA)] and 22:6n‐3 [docosahexaenoic acid (DHA)] levels, compared with the levels in yeast strains themselves, was more pronounced in the 22:6n‐3 level of Moina fed the C. austromarina, resulting in a high DHA:EPA ratio. When the Moina diets were switched, their δ13C values shifted gradually towards the values of the switched diets. Diet switch from Erythrobacter sp. Sπ‐I to C. austromarina Yeast‐16 resulted in a more rapid turnover of Moina tissue carbon than that in the inverse case. When fed a mixed diet, the δ13C values of Moina tissue approached the value of marine yeasts immediately. These temporal changes in the δ13C values of Moina tissue indicate the preferential ingestion of marine yeasts and a selective assimilation of the carbon originated from marine yeasts. These findings suggest that marine yeasts, particularly C. austromarina Yeast‐16, are highly available to mass cultures of M. macrocopa, providing better nutritional and dietary values than the commercial diet (Erythrobacter sp. Sπ‐I).  相似文献   
104.
  1. Detailed knowledge about the distribution of species in need of protection is required for the management of Marine Protected Areas, a major tool to reduce marine biodiversity loss. Such knowledge is deficient for most marine invertebrates.
  2. Axinella polypoides is a marine sponge included on the list of protected species by the Barcelona Convention (1976) and the Bern Convention (1987). This large and erect species has an important ecological role in habitat forming and benthic–pelagic coupling.
  3. Bathymetrical, geographical and ecological data over the last 60 years were collated from publications and reports, together with new surveys to assess the distribution and protection status in Liguria of A. polypoides. It identified a more widespread distribution than previously thought, which points at a general need for dedicated investigations on the occurrence of species that require protection.
  4. Bathymetrical distribution was trimodal, with peaks corresponding to different geomorphological settings: coastal cliff bases (around 38 m depth), inner shelf shoals (52 m) and rocks amidst coarse sediment on the outer shelf (79 m). Density was significantly greater at the shallowest depths. The species was mostly found in the coralligenous biocoenosis, in association with other characteristic species or forming a monospecific facies.
  5. On (sub)vertical cliffs, A. polypoides often exhibited an unusual cane shape, rather than the typical bushy morphology, thus causing confusion with the congeneric A. cannabina, a more southern species. Records of the latter in the Ligurian Sea therefore need confirmation.
  6. Only a minority (22.6%) of A. polypoides records were in Marine Protected Areas, the remainder being located in areas with no current environmental protection plans in place. While the occurrence of this species in MPAs remained stable over the decades, the only quantitative historical data available indicated that populations in non-protected areas were declining owing to anthropogenic impacts (fishing and anchoring).
  相似文献   
105.
  1. The implementation of marine protected areas (MPAs) has been widely used as a tool to manage and conserve marine resources and services. Yet, to date, the reserve effect is still weakly evaluated, particularly for soft-sediment habitats.
  2. The Arrábida MPA, considered as a biodiversity hotspot, was fully established in 2009 on the west coast of Portugal and is characterized by large expanses of soft-sediment habitats. This MPA was established to protect biodiversity and to ensure the livelihood of the local small-scale fisheries community.
  3. Beyond before–after-control–impact (BACI) analyses were carried out on catch data (abundance and biomass) of 351 trammel net sets from experimental fishing campaigns (2007–2019) to study the reserve effect on demersal fish populations.
  4. The results show a declining trend in abundance inside and outside the protected area, with significant positive effects only found for undersize commercial species and Solea senegalensis, and a general increase in fish species total length. Despite the lack of any obvious reserve effect, the increase in fish length can be considered as a first sign.
  5. Anthropogenic pressures are generalized around the area, and transgressions of the restrictions are frequently observed inside the no-take zone. These can, among other aspects, delay or prevent the expected reserve effects. Therefore, enforcement and/or modification of the spatial plan must be incentivized to achieve the goals of the MPA.
  相似文献   
106.
  1. The most western little penguin colony globally, and the most northern in Western Australia (WA) is found on Penguin Island, WA. The penguins use coastal bays that are also used extensively by recreational watercraft. These penguins have been found to either dive predominantly to shallow depths of 1–5 m or to depths >8 m. It is thus hypothesized that (a) both the shallow and deeper diving penguins can potentially be disturbed or injured by these watercraft but that the risk will differ between the two diving strategies, and (b) that risk of injury for both is greater during the summer and autumn, when people are more likely to use watercraft.
  2. This was tested by attaching data loggers to little penguins during chick rearing and by investigating necropsy records. Diving activity was studied for the very shallow and relatively deeper diving penguins separately, and we considered the penguins were vulnerable to interactions with watercraft when they were within the top 2 m of the water column or at the surface.
  3. Shallow‐diving penguins executed >1,200 dives per day, 64% of dives occurred within the top 2 m, and they were vulnerable for approximately two‐thirds of their time at sea. The deeper diving penguins executed fewer dives. Almost half of dives were to ≥10 m, yet they were vulnerable for almost one‐third of their time at sea. Their post‐dive recovery was also longer. Thus, the risk of interaction from watercraft differs depending on the diving behaviour.
  4. This study highlights the potential impact to little penguins throughout Australia and New Zealand.
  相似文献   
107.
108.
Currently, as many as 30 million coral reef fish belonging to 1,000 species are collected annually to supply private and public aquaria around the world. In addition, over 100 species of invertebrate are used, involving hundreds of thousands or even millions of individuals. The majority of these specimens come from coral reefs and associated habitats, with about 45 countries supplying the ornamental market. Considering the many pressures currently faced by reefs it is vital that ornamental fisheries are investigated and monitored, and management strategies formulated to ensure they are sustainable. This requires research, monitoring, training, use of non-damaging collecting methods and adoption of conservation strategies for controlling catch, such as reserves, quotas and closed seasons. There are also a number of possibilities for enhancing the fishery, such as mariculture and construction of artificial reefs. This paper concentrates on some of the conservation measures that can be taken and discusses their application and effectiveness. Such measures include limiting collecting effort, establishment of species-based or overall quotas, restrictions on rare and/or endemic species, temporary closures and establishment of fisherybreak reserves.  相似文献   
109.
以海洋低温蛋白酶生产菌株YS-9412-130为研究对象,从传代、菌龄、溶菌酶浓度与酶解时间、甘氨酸与EDTA预处理以及稳定剂对该菌原生质体形成与再生的影响进行研究。结果表明,在相同条件下,第一代菌至第五代菌原生质体的形成率分别为86.9%、70.3%、66.8%、63.4%、60.2%,再生率分别为10.5%、18.6%、17.9%、18.2%、17.8%;取该菌对数生长前期、对数生长中后期、稳定期部分菌液制备原生质体,原生质体的形成率分别为72.1%、70.4%、60.5%,再生率为13.4%、18.9%、10.4%;溶菌酶浓度为2.5mg/mL、5mg/mL、10mg/mL、20mg/mL,酶解60min,原生质体的形成率分别为40.6%、70.8%、81.8%、95.6%,原生质体的再生率为19.0%、19.2%、19.0%、10.6%;使用10mg/mL溶菌酶酶解YS-9412-130菌30min、60min、90min、120min,原生质体的形成率分别为30.8%、81.3%、81.7%、82.9%,原生质体的再生率分别为19.2%、19.3%、16.9%、11.2%;在细菌培养液中添加终质量浓度为5mg/mL、10mg/mL、20mg/mL和40mg/mL的甘氨酸,培养该菌16h后制备原生质体,原生质体的形成率分别为81.0%、81.1%、90.3%、90.8%、90.6%,再生率为19.1%、19.0%、19.3%、12.0%、9.0%;EDTA对原生质体的形成稍有促进作用,但作用超过30min会影响原生质体的再生;分别以0.6mol/L Kcl、0.3mol/L KCl+0.3mol/L蔗糖、0.6mol/L蔗糖作为稳定剂,原生质体的再生率分别为10.9%、19.6%、25.9%。结论认为,YS-9412-130原生质体制备的最佳条件为选用第2代YS-9412-130菌,在培养基中添加终质度浓度为10mg/mL的甘氨酸培养16h后,再将菌体置于含有0.05mol/LEDTA的高渗溶液中30℃预处理30min,用10mg/mL溶菌酶,30℃酶解60min,再用0.6mol/L蔗糖作为原生质体再生培养稳定剂,比较适合于YS-9412-130原生质体的制备与再生。这一试验结果将为通过原生质体技术对YS-9412-130菌进行遗传改良提供重要参数。  相似文献   
110.
Spatially explicit fisheries simulation models for policy evaluation   总被引:3,自引:0,他引:3  
This paper deals with the design of modelling tools suitable for investigating the consequences of alternative policies on the dynamics of resources and fisheries, such as the evaluation of marine protected areas (MPA). We first review the numerous models that have been developed for this purpose, and compare them from several standpoints: population modelling, exploitation modelling and management measure modelling. We then present a generic fisheries simulation model, Integration of Spatial Information for FISHeries simulation (ISIS‐Fish). This spatially explicit model allows quantitative policy screening for fisheries with mixed‐species harvests. It may be used to investigate the effects of combined management scenarios including a variety of policies: total allowable catch (TAC), licenses, gear restrictions, MPA, etc. Fisher's response to management may be accounted for by means of decision rules conditioned on population and exploitation parameters. An application to a simple example illustrates the relevance of this kind of tool for policy screening, particularly in the case of mixed fisheries. Finally, the reviewed models and ISIS‐Fish are discussed and confronted in the light of the underlying assumptions and model objectives. In the light of this discussion, we identify desirable features for fisheries simulation models aimed at policy evaluation, and particularly MPA evaluation.  相似文献   
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