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71.
Marion E. Wittmann Sudeep Chandra John E. Reuter Andrea Caires S. Geoffrey Schladow Marianne Denton 《水产资源保护:海洋与淡水生态系统》2012,22(5):588-597
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The aim of this review is to clarify the relation between Italian aquaculture and the introduction on alien species in Italy. In Italy, the most common aquatic alien species are rainbow trout and Manila clam, and they represent main economic product of Italian aquaculture. Wels catfish and red clawed crayfish have been voluntarily or involuntarily introduced for aquaculture scope, and they are now the most invasive alien aquatic species. Other alien naturalized species, as some salmonid species, are important economic resources in north Italy for inland professional fishery and are considered worthwhile of conservation. Thus, aquaculture is directly or indirectly responsible of the introduction of several alien species in Italy, but its effect on alien species diffusion is peculiar, as few successfully farmed species have become rapidly common. Until now, conventional aquaculture has played main role in the diffusion of alien species in Italy, while ornamental aquaculture will be the main source of alien introductions in the future. 相似文献
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Evaluating potential competitive bottlenecks between invasive common carp and native bluegill and yellow perch 下载免费PDF全文
Processes influencing fish recruitment are often highly complex and inherently difficult to understand. Invasive species may complicate recruitment through habitat and food web modifications resulting in competitive bottlenecks. Common carp Cyprinus carpio have been distributed worldwide, and their introductions have resulted in destructive effects on aquatic ecosystems and food web dynamics. Common carp are highly fecund, and high densities of age‐0 carp may occur in some years that may reduce invertebrate prey resources and adversely affect native age‐0 fishes. We used enclosures and field observations to examine potential effects of age‐0 common carp on growth and survival of age‐0 yellow perch Perca flavescens and bluegill Lepomis macrochirus. Yellow perch and bluegill were stocked into enclosures with and without common carp (31 fish/m3) using a substitution experimental design, and fish growth and survival and invertebrate prey resources were assessed. Common carp reduced growth of yellow perch but not bluegill and did not affect survival of either species in mesocosms. Next, we used patterns of common carp, bluegill, and yellow perch abundance and total length across 38 lake‐years to evaluate potential interspecific interactions in natural systems. Age‐0 common carp abundance was not negatively related to size or abundance of bluegill or yellow perch. However, adult common carp and age‐0 yellow perch abundance were inversely related, suggesting a potential competitive bottleneck. Thus, age‐0 common carp may suppress growth of yellow perch when prey is limited, but adult common carp may have larger effects than early life stages on native juvenile fishes. 相似文献
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Patrícia Mendon?a Pauletti Lucas Silva Cintra Caio Guedes Braguine Ademar Alves da Silva Filho Márcio Luís Andrade e Silva Wilson Roberto Cunha Ana Helena Januário 《Marine drugs》2010,8(5):1526-1549
This review discusses the isolation, structural elucidation, and biological activities of halogenated indole alkaloids obtained from marine invertebrates. Meridianins and related compounds (variolins, psammopemmins, and aplicyanins), as well as aplysinopsins and leptoclinidamines, are focused on. A compilation of the 13C-NMR spectral data of these selected natural indole alkaloids is also provided. 相似文献
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Mohamed Elamir F. Hegazy Tarik A. Mohamed Montaser A. Alhammady Alaa M. Shaheen Eman H. Reda Abdelsamed I. Elshamy Mina Aziz Paul W. Paré 《Marine drugs》2015,13(5):3154-3181
Marine invertebrates including sponges, soft coral, tunicates, mollusks and bryozoan have proved to be a prolific source of bioactive natural products. Among marine-derived metabolites, terpenoids have provided a vast array of molecular architectures. These isoprenoid-derived metabolites also exhibit highly specialized biological activities ranging from nerve regeneration to blood-sugar regulation. As a result, intense research activity has been devoted to characterizing invertebrate terpenes from both a chemical and biological standpoint. This review focuses on the chemistry and biology of terpene metabolites isolated from the Red Sea ecosystem, a unique marine biome with one of the highest levels of biodiversity and specifically rich in invertebrate species. 相似文献
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