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Abstract: Many rare and endangered species are difficult to locate, observe, and study. Consequently, many individuals, breeding pairs, and even populations of such species could remain undetected. Genetic markers can potentially be used to detect the existence of undiscovered individuals and populations, and we propose a method to do so that requires 3 conditions. First, sampling of the known population(s) of the target species must be comprehensive. Second, the species must display a reasonable level of philopatry and genetic structuring. Third, individuals must be able to be caught outside of breeding locations (e.g., at courtship or feeding areas, in flight), and the level of recapture must be reasonably high. We applied our method to the Chatham Island Taiko (Pterodroma magentae), one of the world's most endangered seabirds. We sequenced the Taiko mitochondrial cytochrome b gene and both copies of a fragment of the duplicated domain I of the control region. Twenty‐one haplotypes were revealed, including 4 (19%) not found in birds at known burrows. These results suggest there are more burrow groups yet to be located. The species is a pelagic gadfly petrel that inhabits land only in the breeding season during which it is nocturnal and nests in burrows. Taiko burrows are situated in dense forest in a remote area of Chatham Island, and are consequently difficult to locate and study. It is important that all Taiko burrows be discovered to enable monitoring and protection of the birds from exotic predators.  相似文献   

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In general tropical forage legumes lack microsatellites or simple sequence repeat (SSR) markers. Development of genic SSR markers from expressed sequence tagged (EST) database is an alternate and efficient approach to generate the standard DNA markers for genome analysis of such crop species. In the present paper a total of 816 EST-SSRs containing perfect repeats of mono (33.5%), di (14.7%), tri (39.3%), tetra (2.7%), penta (0.7%) and hexa (0.4%) nucleotides were identified from 1,87,763 ESTs of Medicago truncatula. Along with, 70 (8.5%) SSRs of a compound type were also observed. Seven primer pairs of tri repeats were tested for cross transferability in 19 accessions of forage legumes comprising 11 genera. At two different annealing temperatures (55 and 60 degreesC) all primer pairs except AJ410087 reacted with many accessions of forage legumes. Atotal of 51 alleles were detected with six M. truncatula EST-SSRs primer-pairs against DNAfrom 19 accessions representing 11 genera where number of alleles ranged from 2 to 13. The cross-transferability of these EST-SSRs was 40.6% at 55 degreesC and 32.3% at 60 degreesC annealing temperature. 24 alleles of the total 50 (48%) at 55 degreesC and 27 of 51 (53%) at 60 degreesC were polymorphic among the accessions. These 27 polymorphic amplicons identified could be used as DNA markers. This study demonstrates the developed SSR markers from M. truncatula ESTs as a valuable genetic markers and also proposes the possibility of transferring these markers between species of different genera of the legumes of forage importance. It was evident from the results obtained with a set of Desmanthus virgatus accessions where SequentialAgglomerative Hierarchical and Nested (SAHN) cluster analysis based on Dice similarity and Unweighted Pair Group Method with Arithmetic mean Algorithm (UPGMA) revealed significant variability (24 to 74%) among the accessions. High bootstrap values (>30) supported the nodes generated by dendrogram analysis of accessions.  相似文献   

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结合钱绍昌教授提出的电影语言的五个特点,提出影视翻译的特殊要求即应以译语观众为中心和译者要考虑电影翻译的技术因素制约.文化意象是一种文化符号,承载着独特、广阔、深沉的文化内涵,不同民族的文化差异导致的文化意象的空缺与错位往往使译者处于两难的境地.译者可从文化交流的角度和尊重影视翻译自身特点的基础上,选用译语观众所熟悉的和易于理解的词语以直译,意译,直译意译结合三个方法来传递和翻译文化意象.参4.  相似文献   

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加拿大污染场地的管理方法及其对我国的借鉴   总被引:3,自引:0,他引:3  
详细介绍了加拿大对污染场地的管理方法,即包括识别可疑场地、场地历史调查、初步采样测试、场地分类、详细采样测试、场地再分类、制定修复管理措施、实施修复管理措施、确认采样和最终报告、长期监测的10步管理流程,并说明了各步骤涉及的若干指导性文件,最后探讨了加拿大污染场地管理方法对我国建立污染场地管理体系的借鉴意义.  相似文献   

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A Practice-based Approach to Ecosystem Management   总被引:4,自引:0,他引:4  
Ecosystem management is a rapidly evolving philosophy or paradigm of natural resource management intended to sustain the integrity of ecosystems. The problem is that principles of ecosystem management are unsatisfactory for practical purposes. Three major approaches to the problem are evaluated: (1) clarification of the goals of ecosystem management, (2) construction of a better scientific foundation for management decisions, and (3) comparative appraisal of current practices. The evaluation concludes that neither of the first two approaches is necessary or sufficient for better management decisions because better decisions depend upon the complexities of particular contexts. The third, practice-based approach makes the most of the limited human capacity to cope with the complexities of ecosystem management in order to improve principles of ecosystem management, to inform particular management decisions through improved principles, and to incorporate clearer goals and a better scientific foundation as they become available. The evaluation draws on experience and disciplines beyond conservation biology and natural resource management, including policy sciences.  相似文献   

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本文根据耗散结构的基本理论,结合生产实践经验,提出了表征土壤肥力的非线性微分方程:=(K-b)x-βx2X─土壤生物活性,t─时间,K─生物繁殖系数,b─生物死亡系数,β─生物饱和系数.解这个并不复杂的非线性微分方程,便可知道土壤是处于热力学分枝,还是耗散结构分枝.这对研究土壤肥力的动态变化、土壤肥力的分类、土壤的管理、土壤退化的防止等方面有着无法预测的应用前景.  相似文献   

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