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21.
利用ISSR分子标记检测老化扁蓿豆种质遗传完整性的变化   总被引:2,自引:0,他引:2  
采用ISSR分子标记,对经老化处理的不同发芽率水平扁蓿豆种质进行遗传完整性分析。结果表明:用10个有效引物对4个不同发芽率居群进行PCR扩增,共检测到48个等位基因,每个位点的等位基因数为3~8个,平均为4.8个;老化处理群体的多态性位点百分率(PPB)、等位基因数(Na)、有效等位基因数(Ne)、基因多样性指数(H)、Shannon指数(I)等遗传参数,与对照群体的遗传参数相比都有所下降,表明老化处理后群体内的遗传多样性低于对照群体的遗传多样性;与对照群体相比,发芽率为20%时,各遗传参数呈极显著性差异,说明扁蓿豆种质更新发芽率临界值在20%~40%;ISSR分子标记可以作为老化扁蓿豆种子遗传完整性变化的检测方法,同时认为对于异质种质资源材料,低发芽率更新标准不利于种质资源遗传完整性的保持。  相似文献   
22.
“中国野生动物之乡”命名活动   总被引:1,自引:0,他引:1  
梦梦  尹峰 《野生动物》2012,33(2):105-107
野生动物是自然生态系统的重要组成部分,在促进人与自然和谐发展、维护生态平衡等方面发挥着重要作用。为了加强野生动物资源的保护,调动野生动物栖息地地区公众保护鸟类的积极性,提高公众野生动物保护的意识,促进人口、资源、环境和经济的协调发展,中国野生动物保护协会自2004年起在全国组织开展了“中国野生动物之乡”命名活动,受到了社会各界的广泛欢迎。截止2011年8月,中国野生动物保护协会共在全国23个省(区、市)命名了50个“中国野生动物之乡”。作为野生动物保护宣传的新模式,“中国野生动物之乡”对于加大提高公众的保护意识,树立地方的生态品牌,调动社会各界的保护积极性起到了促进作用。  相似文献   
23.
In its 40‐year history, the science of conservation has faced unprecedented challenges in terms of environmental damage and rapid global change, and environmental problems are only increasing as greater demands are placed on limited natural resources. Conservation science has been adapting to keep pace with these changes. Here, we highlight contemporary and emerging trends and innovations in conservation science that we believe represent the most effective responses to biodiversity threats. We focus on specific areas where conservation science has had to adjust its approach to address emerging threats to biodiversity, including habitat destruction and degradation, climate change, declining populations and invasive species. We also document changes in attitudes, norms and practices among conservation scientists. A key component to success is engaging and maintaining public support for conservation, which can be facilitated through the use of technology. These recent trends in conservation and management are innovative and will assist in optimizing conservation strategies, increasing our leverage with the general public and tackling our current environmental challenges.  相似文献   
24.
中国水土流失问题的初探   总被引:6,自引:0,他引:6  
长期以来,水土流失直接威胁着人们赖以生存的环境,在所有的生态破坏中,水土流失称之为“环境破坏第一杀手”。针对我国山地丘陵面积大、地质条件复杂、人为破坏加速、水土流失严重的实际情况,通过丰富的历史资料和整治经验及野外工作所积累的大量数据分析,以生态恢复学为指导,总结了水土流失的基本特点,研究了水土流失治理与经济可持续发展的关系,探讨了水土流失给生态安全造成的巨大危害,展望了水土保持的预期目标,根据中国的实际情况,提出了综合治理的基本思路。  相似文献   
25.
A rare and almost complete barnacle fossil, previously described on the basis of two isolated shell fragments, was recently exposed in a limestone block on the outer wall of Melbourne's Old Magistrates' Courts in Victoria, Australia. These courts comprise one of the oldest and grandest buildings in Melbourne and because of this they have a heritage listing. As heritage‐listed buildings are protected from alteration by law, and as removal of the fossil would be deemed “alteration”, official permission had to be obtained to extract the specimen. This paper discusses the processes involved with extraction of a unique specimen from a protected building and provides an overview of the palaeontological significance of the fossil. Consideration is given to the likely fate of a fossil of this nature, situated a little below eye level on a busy city street, if it was left in situ; finally, the implications of designating a holotype from material removed from a building are assessed.  相似文献   
26.
Here, we present the results of a genetic analysis of 463 Pottoka ponies corresponding to four generations, using 17 microsatellite markers. Ten years after the beginning of the Pottoka conservation programme, the values for the genetic diversity of the breed are still high and stable, indicating the success of the programme. We found null alleles in Pottoka for the ASB23, HMS3 and HTG10 microsatellites. Together with information obtained from other pony breeds from the Iberian Peninsula, this finding indicates that these microsatellites should not be used for phylogenetic analyses or parentage tests, at least for these breeds. The high heterozygosity exhibited by this breed in comparison to other ponies, together with its genetic proximity to the centroid of the allele frequencies, suggest that Pottoka allele frequencies are close to those initially exhibited by the ancestors of current European ponies. The results obtained in the current work, together with results from previous studies of ponies and horses from the Iberian Peninsula, corroborate the idea of a unique origin of all ponies from the European Atlantic Area. In contrast, our results do not corroborate the idea that these are derived from a domestication event in the Iberian Peninsula, nor that they have incorporated ancient Iberian horse genes into their genetic pool to a larger extent than other horse breeds.  相似文献   
27.
侵蚀果园长期植草的生态效益分析   总被引:1,自引:0,他引:1  
针对山地果园不合理开发引发的土壤侵蚀和土壤退化问题,将适生牧草套种于幼龄侵蚀果园,开展水土流失、土壤肥力及果树生长的定位观测。结果表明:套种平托花生(Arachis pintoi)、圆叶决明(Chamaecrista rotundifolia)1~12年,年地面径流系数0~0.0136,均值为0.007左右,仅为清耕处理的1/10,基本无土壤侵蚀发生;套种11年,套种区0~30 cm土层的土壤pH值比清耕分别提高0.25~0.30个单位,0~15 cm土层土壤有机碳、碱解氮、有效磷质量分数比清耕提高7.595~6.728 g·kg-1,26.84~31.89 mg·kg-1,3.57~4.62 mg·kg-1;轻组有机碳质量分数在0~30 cm土层呈套种平托花生>套种圆叶决明>清耕的变化趋势,重组有机碳质量分数在0~15cm土层亦呈相同变化趋势。套种处理有助改善果肉糖酸比和商品果率,牧草综合利用可明显提升果园建园初期的经济效益,尽管套种处理给果树带来一定的减产。  相似文献   
28.
A spotlight on snow leopard conservation in China   总被引:1,自引:0,他引:1       下载免费PDF全文
China holds the greatest proportion of the snow leopard's (Panthera uncia) global range and is central to their conservation. The country is also undergoing unprecedented economic growth, which increases both the threats to the snow leopard and the opportunities for its conservation. In this paper we aim to review published literature (from 1950 to 2014) in English and Mandarin on snow leopard ecology and conservation in China in order to identify thematic and geographic research gaps and propose research priorities. We first retrieved all published items that considered snow leopards in China (n = 106). We extracted from these papers 274 reports of snow leopard presence in China. We then reviewed a subset of papers (n = 33) of this literature, which specifically focused on snow leopard ecology and conservation within China. We introduced a thematic framework that allows a structured and comprehensive assessment of findings. This framework recognizes 4 critical and interrelated topics underpinning snow leopard ecology and conservation: habitat (distribution and protected area coverage); prey (distribution and abundance, predator–prey relationships); human interactions (hunting and trade, livestock interactions and conflicts); and the underlying policy context. Significant gains in knowledge as well as research gaps and priorities are discussed with reference to our framework. The modest quantity and limited scope of published research on the snow leopard in China calls for a continued and intensified effort to inform and support national conservation policies.  相似文献   
29.
《African Zoology》2013,48(3):205-217
Molecular genetic techniques, such as DNA barcoding and genotyping, are increasingly being used to assist with the conservation and management of chondrichthyans worldwide. Southern Africa is a shark biodiversity hotspot, with a large number of endemic species. According to the IUCN Red List, a quarter of South Africa's chondrichthyans are threatened with extinction. South Africa's commercial shark fisheries have increased over the last decade and there is a need to ensure sustainable utilisation and conservation of this fisheries resource. Here, we give an overview of the molecular techniques that are used to assist in the identification of species, cryptic speciation and possible interspecific hybridisation, as well as the assessment of population structure and reproductive behaviour of endemic and commercially important chondrichthyan species of southern Africa. We discuss the potential application of these techniques for management and conservation of several species affected by South African fisheries. Acquiring baseline barcode data of all chondrichthyans in southern African waters and assessing the population structure of exploited species on a local and greater regional scale are recommended as research priorities. Future prospects should also include high-throughput molecular marker development and investigation of intraspecies functional variation using next generation sequencing technology.  相似文献   
30.
阐述了四川牦牛遗传资源的保存方法和利用途径。这将有助于四川牧区畜牧业的可持续发展  相似文献   
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