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2006年9月14日,联合国环境规划署和《养护野生动物移栖物种公约》、《关于养护黑海、地中海和毗连大西洋海域鲸目动物的协定》和《养护波罗的海和北海小鲸类协定》这三个公约的秘书处宣布,共同发起“2007国际海豚年”活动。这似乎是一件令人欣喜的事,但正如被列入  相似文献   
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The timing of river entry in the Atlantic salmon is known to depend on genetic, demographic and environmental factors, but little is known about the relative magnitude of among population and among year variation and covariation in this respect in natural state Atlantic salmon rives. To investigate this, variability in the timing of river entry in three historical Finnish Atlantic salmon populations were analyzed using salmon trap data collected during 1870- 1902. The analyses reveled that 1 ) the timing of river entry differed substantially and consistently among the rivers, and that 2) variation among the rivers was much larger than variation among years. Annual variations were not explained by regional environmental conditions, whereas in one river the timing of the local flood peak was a significant predictor of the timing of river entry. Differences in the timing of salmon entry to geographically closely situated rivers suggests that a regionally fixed opening date for coastal fisheries might not be the best management strategy as it may lead to uneven exploitation of salmon populations from different rivers [ Current Zoology 55 (5) : 342 - 349, 2009] .  相似文献   
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琥珀是一种经过石化作用形成的天然树脂化石,亦是一种有机宝石。琥珀在全球范围分布较广,尤其在欧洲的波罗的海、中美洲的多米尼加-墨西哥、亚洲的缅甸等区域有着大量的发现。全球各地琥珀中,昆虫包裹体最为常见,脊椎动物包裹体数量较少。但相对保存于沉积岩中的传统脊椎动物化石来说,保存于琥珀中的脊椎动物包裹体可以额外提供生物体的软组织、原始死亡状态、生存环境等信息,且可以保存比传统骨骼化石更直观、立体、精细的生物形态学信息,为研究生物演化、恢复古环境、古生态和古行为学等方面提供了重要的依据。文中主要总结了来自全球各琥珀产区迄今为止发现的各种脊椎动物包裹体,包括了非鸟恐龙、鸟类、哺乳类、爬行类、两栖类等,以及它们背后隐藏的演化信息,并对未来的研究方向与趋势做了初步的展望。  相似文献   
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【背景】在地衣共生系统中除了共生真菌、藻类以外,还蕴藏着丰富的放线菌资源。【目的】采集来自云南西双版纳、白茫雪山、德国波罗的海南岸3个地区的地衣,对获得的地衣纯培养放线菌进行多样性分析。【方法】采用3种放线菌选择分离培养基,通过平板稀释涂布法分离放线菌。通过比较16S rRNA基因序列相似性以及构建系统发育树,确定纯培养放线菌的分类地位。【结果】共分离菌株1 123株,鉴定417株。其中从西双版纳17份地衣样品中分离纯化到107株放线菌,分布在7个目14个科33个属,潜在新种18株,其中链霉菌为优势菌属;从白茫雪山7份地衣样品中分离纯化到103株放线菌,分布在4个目5个科9个属,潜在新种16株。其中链霉菌为优势菌属,占比39%;从波罗的海南岸5份地衣样品中分离纯化到65株放线菌,分布在4个目8个科18个属,潜在新种5株,潜在新种菌和链霉菌为优势菌属。【结论】在本研究条件下,西双版纳可培养地衣放线菌多样性较白茫雪山和波罗的海南岸丰富。白茫雪山地衣链霉菌居多,潜在新种占比15.5%。3个地区地衣放线菌的区系组成各不相同,这与3个地区地衣所处地理环境、完全不同的气候密切相关。  相似文献   
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波罗的海放线菌的多样性   总被引:2,自引:0,他引:2  
姜怡  曹艳茹  王茜  靳荣线 《微生物学报》2011,51(11):1461-1467
摘要:【目的】为了探索海洋放线菌的多样性,为发现新的药物先导化合物提供新菌源,我们分析了波罗的海的放线菌多样性及生物活性。【方法】采集100 份底泥样品,用7 种培养基分离放线菌809 株;去掉相同菌株后,选择280 株代表菌进行了初步分类鉴定;采用琼脂扩散法,检测了它们对5 种细菌、真菌的抗菌活性;用API ZYM system 测定了21 种酶的活性。【结果】用海藻糖-脯氨酸培养基和HV 培养基分离的放线菌中,稀有放线菌占60% 和63% ;波罗的海的放线菌有15 个属,其中3 个属是首次从海洋中分离  相似文献   
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The population density of the white-tailed sea eagle Haliaeetus albicilla is very low in many countries. In last twenty years, the sea eagle population in South Bohemia was restored by strict protection subsidized by reintroduction, The active help consisted of feeding during winter and building of artificial nests. A new sea eagle breeding population arose in the Treboǎ basin area in the early 1980' s. Until this time sea eagles had used former breeding places only for wintering, probably coming from the Baltic. The South Bohemian sea eagle population is very unique: it exists in a densely man-occupied landscape, mainly in areas with very intensive carp breeding in artificial fishponds and was partly artficially (help to wintering birds and reintroduction of some individuals) restored. The experience from South Bohemia may have importance for populations of the sea eagle in other areas of its occurence, primarily in the continental conditions [ Current Zoology 55 (5) : 315 - 318, 2009].  相似文献   
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