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World Sturgeon Conservation Society e.V. (WSCS)   总被引:1,自引:0,他引:1  
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Acipenser oxyrinchus is considered extirpated in Europe, but numerous breeding populations still exist on the Atlantic coast of North America. An adult female A. oxyrinchus, 2500 mm total length and 120 kg wet weight, was accidentally fished on 24 November 2010 near the coast of Gijón, Asturias, Spain. The fish was identified by its morphological pattern as well as by mitochondrial and nuclear DNA analyses. Because the sturgeon was found far away from any known breeding area, it was considered a stray or vagrant specimen. It certainly has a natural origin, but its eventual birthplace could not be determined. Because its current occurrence was unknown in southwestern Europe until now, the species is not cataloged or protected in this area. Therefore, the residual European stocks of A. oxyrinchus ought to be listed as Critically Endangered (CR) according to the IUCN categories. Likewise, it is imperative for southwestern European countries with an historic or recent occurrence of A. oxyrinchus to protect the species through domestic and international legislation. The present sympatric occurrence of A. sturio and A. oxyrinchus raises new challenges about key questions, such as the species selection for restoration program in European countries. Accurate monitoring is mandatory to obtain appropriate information for an assessment of the current occurrence of A. oxyrinchus in southwestern Europe.  相似文献   

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The Coastal Wetlands Management Project (CWMP), funded by the Global Environment Facility and implemented by the Ghana Wildlife Department, seeks to preserve the ecological integrity of coastal lagoons that serve as important sites for migratory waterbirds. This report describes the geomorphology, hydrology, soils, water chemistry, and vegetation of the Muni-Pomadze Ramsar site. Muni lagoon is a saline, shallow water lagoon separated from the sea by a sand bar which may be breached occasionally. The bulk of the rainfall in the catchment evaporates or flows as surface runoff into three streams that empty into Muni lagoon. Open water in the lagoon varies seasonally from 100 ha in the dry season to over 1000 ha in the wet season. The natural flora of the site can be divided into four main types; flood plain (including mangrove and wetland vegetation), dune vegetation, riverine vegetation, and terrestrial vegetation on elevated ground. The latter consists of a combination of grasslands, thickets, and Eucalyptus plantations. Fifty-three percent of the site is classified as natural vegetation. An additional 32.5% is agricultural land and 12.6% is residential area for the 11 communities within the site. The main source of employment are farming or fishing. The area surrounding Muni lagoon is used extensively for bushmeat hunting and as the tribal hunting grounds of the Efutu people. Apart from the global importance of the Muni-Pomadze site for biodiversity, management of the site is further justified by its considerable potential for development as an income-generating and educational nature reserve with an eco-cultural theme, managed by the local communities in partnership with the governmental and non-governmental conservation agencies.  相似文献   

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The purpose of this paper was to analyze the diversity patterns of Cactaceae at a global scale, to identify those countries where conservation actions should be performed. In order to do this, the species richness and the number of endemic species for 34 American countries were determined. With these data, the relationship between the total number of species or the number of endemic species and the area of the countries were analyzed. In addition, a complementarity analysis was conducted to determine the most important countries for cactus conservation. Results showed that Mexico had the highest number of total and endemic species followed by Argentina, Bolivia, Brazil, and Peru, among others. There was a significant positive relationship between both, the total and endemic species, and the area of the countries. Despite this fact, the cactus diversity in Mexico, Argentina, Peru, Bolivia, Chile, and Costa Rica was higher than expected according to their area. Further, these countries also presented the highest proportions of endemic species. The complementarity analysis indicated that 24 countries are necessary to preserve all cactus species. However, 94% of all species could be preserved with only 10 countries. Considering the diversity patterns and the complementarity analysis, three important groups for cactus conservation were identified: (1) Mexico, Argentina, Peru, Bolivia, Chile, and Costa Rica, (2) Paraguay and Cuba, and (3) Brazil and USA. Conservation efforts should be focused on these countries in order to preserve cactus diversity.  相似文献   

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A variety of collection methods were used to inventory the insect diversity of the Muni-Pomadze Ramsar site along the Ghana coastline. A total of 75 butterfly species in five families were collected and identified. Twenty-six percent of the butterfly species were open country species. The butterflies were all typical of the coastal zone and no endangered or narrowly endemic species were recorded. The Muni-Pomadze site was also rich in other insect species (67 insect species belonging to 15 orders) as a result of the diverse terrestrial habitats surrounding the lagoon. Butterfly species composition changed with habitat indicating a fine-grained response by the butterfly communities to habitat changes. Data from long-term monitoring of butterfly communities at Muni-Pomadze could prove useful as indicators of habitat quality.  相似文献   

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We investigated the age, growth and population structure of lake sturgeon in the Groundhog and Mattagami rivers, northern Ontario, Canada. Age, estimated from counts of annuli in pectoral fin rays, ranged from 1 to 69 years (y) in the 327 fish examined. Growth, expressed as an increase in fork length and calculated from a von Bertalanffy growth equation, slowed from a peak of about 3.9cmyear-1during the early juvenile period (<9y) and approached an asymptote beyond 90y (FL=141.549[–e-0.043(t–4.901)]). A length–mass equation (log M=3.07 log FL–2.26) and conversion factors for fork and total length (FL=0.97 TL–1.154) from our study ranged from 14.5 to 142cm (fork length), 15.5 to 158cm (total length) and 20 to 19730g (live mass) for 1177 individuals. We found no evidence for spawning or recruitment to the population in our study area. Population age and length structure were strongly bimodal, and growth rate appears to have slowed over the past decade. We discuss the possible environmental correlations and conservation implications of this age (size) distribution.  相似文献   

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The participants of the Third International Nitrogen Conference, held in Nanjing, People's Republic of China, 12-16 October 2004. AFFIRM the principles of the Millennium Development Goals and the World Summit on Sustainable Development to speedily increase access to basic human needs such as energy, water, food security and the protection of human health and biodiversity. AFFIRM the scientific findings of the International Nitrogen Conferences and the International Nitrogen Initiative (INI).  相似文献   

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Common preclinical models for testing anticancer treatment include cultured human tumor cell lines in monolayer, and xenografts derived from these cell lines in immunodeficient mice. Our goal was to determine how similar the xenografts are compared with their original cell line and to determine whether it is possible to predict the stability of a xenograft model beforehand. We studied a selection of 89 protein markers of interest in 14 human cell cultures and respective subcutaneous xenografts using the reverse-phase protein array technology. We specifically focused on proteins and posttranslational modifications involved in DNA repair, PI3K pathway, apoptosis, tyrosine kinase signaling, stress, cell cycle, MAPK/ERK signaling, SAPK/JNK signaling, NFκB signaling, and adhesion/cytoskeleton. Using hierarchical clustering, most cell culture-xenograft pairs cluster together, suggesting a global conservation of protein signature. Particularly, Akt, NFkB, EGFR, and Vimentin showed very stable protein expression and phosphorylation levels highlighting that 4 of 10 pathways were highly correlated whatever the model. Other proteins were heterogeneously conserved depending on the cell line. Finally, cell line models with low Akt pathway activation and low levels of Vimentin gave rise to more reliable xenograft models. These results may be useful for the extrapolation of cell culture experiments to in vivo models in novel targeted drug discovery.  相似文献   

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鲟鱼是目前世界上最古老的鱼类之一,其肉质鲜美,营养丰富,鱼卵加工成的鱼子酱具有极高的经济价值。鲟鱼鱼子酱价格居高不下,因此养殖雌性鲟鱼比养殖雄鱼具有更高的经济前景。由于鲟鱼外形无法辨别雌雄,目前,通常借助超声波、内窥镜等仪器进行早期性别鉴定,但鉴别准确性无法保证。因此采用现代分子生物学技术探究鲟鱼性别决定及性别分化机制有助于早期鲟鱼性别鉴定技术的开发及实现鲟鱼全雌化苗种培育。总结了鱼类性别决定与性别分化相关基因的研究现状,综述了目前在鲟鱼上性别决定与性别分化相关基因的研究进展并预测了未来的研究方向及研究趋势。  相似文献   

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Morphological and autoradiographic studies on various hemopoietic tissues in sturgeon are presented. The classic hemopoietic organs characteristic of lower vertebrates, such as the kidney and spleen, are studied as well as unique hemopoietic structures described only in the evolutionarily most ancient fish species (hemopoietic tissues of cartilaginous skull capsules and epicardium). The intensity of cell divisions in hemopoietic foci has been characterized by autoradiography. The results obtained provide a basis for the revision of traditional views about the phylogeny of hemopoiesis. They provide evidence that the osteogenic gravitation of hemopoietic tissue shows up in evolution alongside the appearance of the inner skeleton.  相似文献   

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