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171.
Chang-Keun Kang Hye Young Park Mu-Chan Kim & Won Jae Lee 《Aquaculture Research》2006,37(12):1227-1237
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
172.
Annalisa Azzola Giorgio Bavestrello Marco Bertolino Carlo Nike Bianchi Marzia Bo Francesco Enrichetti Carla Morri Alice Oprandi Margherita Toma Monica Montefalcone 《水产资源保护:海洋与淡水生态系统》2021,31(4):737-747
- 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.
- 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.
- 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.
- 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.
- 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.
- 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).
173.
Lucas Martínez-Ramírez C. Robert Priester Inês Sousa Karim Erzini David Abecasis 《水产资源保护:海洋与淡水生态系统》2021,31(7):1584-1595
- 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.
- 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.
- 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.
- 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.
- 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.
174.
- 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.
- 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.
- 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.
- This study highlights the potential impact to little penguins throughout Australia and New Zealand.
175.
176.
Elizabeth Wood 《Aquarium Sciences and Conservation》2001,3(1-3):65-77
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
177.
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
178.
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
179.
Vasiliki Markantonatou Sylvaine Giakoumi Nikoletta Koukourouvli Irida Maina Genoveva Gonzalez-Mirelis Maria Sini Kostas Maistrelis Mavra Stithou Eleni Gadolou Dimitra Petza Stefanos Kavadas Vasiliki Vassilopoulou Lene Buhl-Mortensen Stelios Katsanevakis 《水产资源保护:海洋与淡水生态系统》2021,31(8):2278-2292
- The expansion and intensification of marine uses have severe cumulative impacts on marine ecosystems and human well-being, unless they are properly managed with an ecosystem-based management approach.
- A systematic conservation planning approach, using marxan with zones , was applied to generate alternative marine spatial plans for the Aegean Sea. Relevant human uses were included and their cumulative impact on a wide set of key biodiversity features was considered in the analysis. Different cost scenarios were developed to gain insight on the effects of the approaches used to assess socio-economic factors, and their potential impact on spatial plans.
- The spatial plans generated differed greatly depending on the method used to estimate opportunity costs and evaluate human activities in monetary terms.
- The vulnerability weights (the relative vulnerability of ecological features to specific human activities and their impacts) that were estimated based on a cumulative impact assessment, allowed the assessment of each zone in contributing to the achievement of conservation targets, through a transparent planning approach.
- Results indicate that special care should be given to how socio-economic activities, their impact on the ecosystems, and related costs are incorporated into planning.
- The proposed approach demonstrates how EU member states may effectively comply with the new Biodiversity Strategy 2030 targets, while planning for the sustainable use of their marine resources.
180.
- Many species and populations of odontocetes have modified their behaviour to take advantage of feeding opportunities provided by fishing activities, with depredation of fishing gear being the most common type of adaptation.
- The northern Adriatic Sea has been identified as an important marine mammal area because of a regular occurrence of common bottlenose dolphins. Boat surveys were conducted within a 3,000 km2 sector of the Adriatic Sea off the coast of Veneto, Italy, between April and October 2018–2019. Based on 76 days at sea, 10,711 km of navigation, and 81 h 26 min of dolphin tracking, this study contributes novel quantitative information on dolphin spatial distribution, and on their occurrence in the wake of beam trawlers, otter trawlers, and midwater pair trawlers.
- A combined generalized additive model and generalized estimation equation framework indicated that trawling—along with other physiographic, biological and anthropogenic variables—influenced dolphin distribution. In days of trawling, the chance of encountering dolphins increased by ~4.5 times (95% confidence interval 1.8–11.0) near active beam trawlers, by ~16.0 times (7.1–36.0) near otter trawlers, and by ~28.9 times (12.0–69.6) near midwater pair trawlers.
- Spatial modelling was used to create maps of predicted distribution, suggesting differences in habitat use between trawling and no-trawling days. Spatial modelling for all days identified a dolphin distribution hotspot of 832 km2, situated off the Po river delta.
- Evidence contributed by this study can be used to inform management action within one of the world's areas most heavily impacted by fishing and other human encroachment. Such management action would help enforce the European Union's Habitats Directive and Marine Strategy Framework Directive, while also informing EU's Maritime Spatial Planning.