Results 41 to 50 of about 19,473 (256)
牛山湖两种优势小型鱼类空间分布与沉水植被的关系! [PDF]
, 2012 运用8种网目规格的成套浮性刺网作为鱼类采样工具,于2005年夏季在长江中游浅水草型湖泊牛山湖进行鱼类定量采样,通过比较不同茂密程度黄丝草生境中的小型鱼类组成、数量和大小结构,探讨此类湖泊小型鱼类的空间分布特征及其与沉水植被的关系.采样期间共捕获13种1124尾鱼,依据其等级丰度和出现频次,和红鳍原!为该湖优势上层小型鱼类.在调查的沉水植物生物量范围内,鱼类物种丰富度和Shannon多样性指数与沉水植物生物量之间呈现倒抛物线关系;两种优势小型鱼类的种群丰度均与沉水植物生物量有着显著的线性正相关关系 ...
刘家寿 +3 more
core
Exploring gaps, biases, and research priorities in the evidence for reptile conservation actions
Conservation Biology, EarlyView.Abstract With over 21% of reptile species threatened with extinction, there is an urgent need to ensure conservation actions to protect and restore populations are informed by relevant, reliable evidence. We examined the geographic and taxonomic distribution of 707 studies that tested the effects of actions to conserve reptiles synthesized in ...
Oliver Speight +9 more
wiley +1 more source
Zhejiang Daxue xuebao. Lixue ban, 2008 目前对于野生双峰驼作为一个独立种的有效性还有着较多争议.研究测定了2头阿尔金山野生双峰驼个体的线粒体细胞色素6基因序列，并结合已有的双峰驼细胞色素b基因序列进行了系统发育分析.结果表明：现有的双峰驼分为2个种群：新疆种群和甘肃种群；2个种群间的遗传距离为2.4%~3.0%，尚未达到种间水平；阿尔金山野生双峰驼属于新疆种群，不能作为一个独立的有效种.
ZHANGYong(张勇) +3 more
doaj +1 more source
, 2012 利用泥鳅(Misgurnus anguillicaudatus)的微卫星引物跨种扩增大鳞副泥鳅(Paramisgurnus dabryanus),通过家系扩增、PCR产物测序筛选出6个座位,用于大鳞副泥鳅7个野生群体的遗传结构分析。结果显示,群体的平均等位基因数在3.167～4.833,平均观测杂合度(Ho)在0.248～0.417,平均期望杂合度(He)在0.379～0.505,多个座位存在零等位基因、杂合子缺失现象,显示大鳞副泥鳅种群遗传多样性较低。采用UPGMA法对7个群体基于DA遗传距离进行聚类,
俞小牧, 游翠红, 童金苟
core
Assessing limits of sustainable seed harvest in wild plant populations
Conservation Biology, EarlyView.Abstract Seed harvesting from wild plant populations is key for ecological restoration, but it may threaten the persistence of the source populations. Consequently, several countries have set guidelines limiting the proportions of harvestable seeds. However, these guidelines are inconsistent and lack a solid empirical basis.
Anna Bucharova +3 more
wiley +1 more source
野生动物学报, 2015 物种谱系是种群管理的必要前提,大猩猩被列为IUCN极危物种。中国动物园大猩猩圈养种群始于1973年,截至2013年12月31日,共有8只存活个体。为了更好地科学管理中国动物园大猩猩圈养种群,对收集到的大猩猩中国区谱系及其扩展谱系进行了统计学与遗传学分析。结果表明,种群平均增长率λ=0.968,呈下降趋势。种群奠基者共14只,潜在奠基者1只。种群保留了野生个体87.24%的基因多样性,无近亲繁殖情况。根据现状分析结果,中国动物园大猩猩圈养种群是一个极小的种群,该种群的发展壮大有待于加强国内自身繁殖 ...
廖 辉 袁 梨 殷毓中 张邓华 姚 勇 钟 灵 周 俊
doaj
Classification and phylogeographical analyses of Siphonaria and Cellana limpets in China and Southeast [PDF]
, 2015 探究岩相潮间带生物的多样性以及分布格局的形成机制不仅有助于我们了解不同时空尺度下历史和当代环境因素的作用结果，而且为全球变化和人类活动背景下预报未来生物群落的动态变化提供了理论依据。快速发展的生物地理学和系统地理学的理论知识和分析方法已成为探究生物多样性的有效工具。本研究在此背景下对广泛分布于中国及东南亚岩相潮间带腹足纲中的帽贝属(Cellana)和菊花螺属(Siphonaria)进行了生物地理学和系统地理学分析，揭示了这两个属的贝类在东南亚沿岸的分布，并讨论了历史和当代因素在塑造嫁虫戚(C ...
王杰
core
A global indicator of species recovery
Conservation Biology, EarlyView.Abstract Monitoring progress toward meeting global biodiversity goals involves several indicators, including, at the species level, the International Union for Conservation of Nature (IUCN) Red List Index (RLI) and the Living Planet Index (LPI). However, at present, there is no indicator specifically for tracking species recovery, despite this being ...
H. Resit Akçakaya +4 more
wiley +1 more source
野生动物学报, 2023 奠基者效应会打破种群遗传结构，使原有种群动态特征失去平衡，加剧遗传多样性的丧失，严重影响物种重引入的遗传多样性和遗传结构。中国麋鹿（Elaphurus davidianus）奠基种群为北京南海子麋鹿苑和江苏大丰麋鹿国家级自然保护区两大种群。为分析中国麋鹿奠基者效应，探究资源遗传多样性及种群结构，揭示中国麋鹿适应环境的遗传机制，以中国两大麋鹿奠基种群为研究对象，基于简化基因组测序，研究北京和江苏2个地区麋鹿的遗传多样性、种群遗传结构及亲缘关系。结果表明：2个种群（18只）共筛选出高质量多态性SNP位点1 ...
张树苗 +9 more
doaj
Finding floral and faunal species richness optima among active fire regimes
Conservation Biology, EarlyView.Abstract Changing fire regimes have important implications for biodiversity and challenge traditional conservation approaches that rely on historical conditions as proxies for ecological integrity. This historical‐centric approach becomes increasingly tenuous under climate change, necessitating direct tests of environmental impacts on biodiversity.
Zachary L. Steel +8 more
wiley +1 more source