Results 31 to 40 of about 17,401 (196)
This population‐comparative study reveals that male and female parents respond differently to social and ecological conditions. This sex‐specific responsive strategy is related to the incongruent parental care systems across populations in Chinese penduline tits.
Jia Zheng +5 more
wiley +1 more source
目的筛选稀有鮈鲫HAN近交系遗传质量检测标记。方法采用鳞片活体移植和同工酶聚丙烯酰胺凝胶电泳法对稀有鮈鲫HAN近交系的遗传纯度进行检测。结果在免疫标记分析中,鳞片同体移植存活率为96.7%以上,野生群体移植存活率为7.4%,而HAN系F22鳞片异体移植的成功率为80%,显著高于野生群体。在生化标记分析中,在HAN系F22中无多态性位点,不同个体的同工酶谱呈现高度一致,在野生群体中有2个多态位点即est2和est3,多态位点的比例为15.56%。结论经过多代近亲交配 ...
曹文宣, 王伟, 王剑伟, 邵燕
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Looking at Us Through Their Eyes. The Analytical Process from Ethnographic Perspectives1
Abstract This article looks at the analytical situation through the Others’ eyes—through examples from contemporary ethnographies of foreign cultures. It discusses the following issues: a) The analogy between the ontological worlds of the dead, ghosts, animals and dreams in “primitive populations” and the analytical psychological descriptions of the ...
Stefano Carta
wiley +1 more source
迁地保护的海南坡鹿种群可以分为野放、半野放和圈养等3种主要类型。野放种群个体数量最多,约占迁地保护种群个体总数的55.3%;其次为半野放种群,其个体数量占35.6%;圈养种群个体数量最少,只占9.1%。半野放是一种较为稳妥的坡鹿种群恢复方式。在海南坡鹿的迁地保护中,应该增加半野放种群个体数量。本文就海南坡鹿的迁地保护提出了7点保护管理及科学研究建议。
卢学理, 袁喜才, 李善元, 张海
doaj
The impacts of coastal defense structures on rocky intertidal community in Yangtze River Delta [PDF]
长江三角洲是长江、黄河以及在此区域的其他河流的活动形成的冲积平原。末次冰期(LastGlacialMaximum,LGM)以后的一万年以来,长江三角洲在海陆交互作用的影响下逐渐扩展。位于长江三角洲地带的近900km的江苏沿岸海岸线除约40km的基岩海岸以外,均为不适宜岩相潮间带生物大量聚集的淤泥质平原海岸。近年来随着中国沿海经济的飞速发展,对土地需求的不断增加,越来越多的沿岸防护建筑正在被修建,成为我国沿岸的“海上长城”。这些沿岸防护建筑显著改变了江苏沿岸的滩涂景观,可能对潮间带群落造成严重影响 ...
黄雄伟
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When and why to give shorebirds a head start
Abstract Headstarting is a translocation technique involving the hatching or rearing of wild eggs or young in captivity and the release of those individuals back to the wild at or before independence. It has been trialed as a conservation intervention for shorebirds over recent decades to improve the population trend of target populations by increasing
Lynda Donaldson +4 more
wiley +1 more source
应用种群管理软件SPARKS 1.6及PMX对中国黑叶猴圈养种群的现状进行了统计分析。截至2012年12月31日,黑叶猴谱系记录了574只个体,目前种群存活个体数量为318只,分布在34家动物园或机构中。圈养种群野外捕获个体主要来源于20世纪70~90年代,目前保持稳定状态。圈养出生个体数则一直保持上升状态,是维持黑叶猴圈养种群增长的主要来源,2012年圈养出生数量占种群总数的87.4%。种群周期增长率λ=1.042,性比M:F=1:1.04,目前种群中能够繁殖的个体共110只(♂48只,♀62只 ...
高喜凤
doaj
麋鹿自1985年重引进中国以来,经过繁殖扩群、行为再塑和野生放养试验3个阶段后,种群数量从79头发展至近7 000头(2018年底),先后形成江苏大丰、湖北石首和湖南洞庭湖野生麋鹿种群。通过对中国麋鹿种群发展现状调查分析,指出目前麋鹿种群健康发展面临的挑战和威胁因素,在扩大奠基种群数量、实施栖息地正向干预、加强疫病防控、开展基因交流等方面探讨中国麋鹿种群健康发展对策。
王立波 1 姜 慧 2 安玉亭 2 杨禹治 3 原宝东 4
doaj
The collective application of shorebird tracking data to conservation
Abstract Addressing urgent conservation issues, such as the drastic declines of North American migratory birds, requires creative, evidence‐based, efficient, and collaborative approaches. The abundance of over 50% of monitored North American shorebird populations has declined by over 50% since 1980. To address these declines, we developed a partnership
Autumn‐Lynn Harrison +71 more
wiley +1 more source
牛山湖两种优势小型鱼类空间分布与沉水植被的关系! [PDF]
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
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