Results 51 to 60 of about 20,824 (277)

中国麋鹿种群现状分析及保护对策探讨

open access: yes野生动物学报, 2020
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  

温带荒漠中温度和土壤水分对土壤呼吸的影响 [PDF]

open access: yes, 2009
荒漠对气候变化具有高度敏感性,深刻认识和量化非生物因子对荒漠生态系统土壤呼吸的影响具有重要意义。采用自动CO2通量系统(Li-8100)监测了梭梭(Haloxylon ammodendron)、假木贼(Anabasis aphylla)和盐穗木(Halostachys caspica)群落生长季土壤呼吸及温度、土壤含水量等,深入分析了水热因子对土壤呼吸的影响。土壤呼吸具有不对称的日格局,最小值出现在8:00,最大值在12:00~14:00。土壤呼吸的季节格局与气温变化基本同步,最小值在生长季末期(10月)
张丽华   +3 more
core  

Using miniaturized laboratory equipment and DNA barcoding to improve conservation genetics training and identify illegally traded species

open access: yesConservation Biology, EarlyView.
Abstract Illegal wildlife trade (IWT) is one of the largest global illegal activities, and it negatively affects biodiversity and sustainable development worldwide. DNA barcoding coupled with high‐throughput sequencing (i.e., metabarcoding) is useful in identifying taxa affected by IWT and has been used routinely for decades.
Maria Joana Ferreira da Silva   +9 more
wiley   +1 more source

浙江长兴扬子鳄种群遗传多样性研究

open access: yes野生动物学报, 2022
为有效保护浙江长兴尹家边扬子鳄保护区扬子鳄(Alligator sinensis)种群,丰富野放扬子鳄的遗传多样性,利用13个微卫星标记分析了该种群的遗传多样性,比较核心区和野放区种群的遗传多样性差异。结果显示:保护区扬子鳄种群共检测到31个等位基因,其中含2个稀有等位基因。野放区种群的平均有效等位基因数量(1.82)、平均观测杂合度(0.49)、平均期望杂合度(0.43)、平均多态信息含量(0.34)和平均香农信息指数(0.64)均低于核心区(1.89、0.52、0.46、0.37和0.70 ...
方黎明   +8 more
doaj  

A Case Study on the Evolution Mechanism of Ambidextrous Competence of Business Incubator among Entrepreneurial Incubation Ecosystem [PDF]

open access: yes, 2016
科技企业孵化机构在扶持区域创业创新活动中的重要性不言而喻。在中国经济转型的大背景下,创业活动之繁荣前所未有,原先服务单一的孵化机构已无法适应创业企业多样化的需求,正在积极向多方资源整合者的角色转变。在实践中,转型成功的孵化机构身上普遍具有同时开展利用式创新和探索式创新的双元能力。因此探索孵化机构发挥双元能力的过程,对促进我国孵化行业发展以及营造区域良好创业孵化生态至关重要。然而学界尚缺乏对孵化机构的双元能力的动态研究,导致科技孵化机构的孵化实践缺乏理论指导而陷入盲目摸索的尴尬状况 ...
许婷
core  

Success of restoration strategies in preventing extirpation of 2 critically endangered coral species

open access: yesConservation Biology, EarlyView.
Abstract An unprecedented marine heatwave in 2023 caused widespread coral bleaching and mortality throughout the Caribbean. In the Florida Keys (USA), 2 foundation species, elkhorn coral (Acropora palmata) and staghorn coral (Acropora cervicornis), were severely affected.
Erinn M. Muller   +29 more
wiley   +1 more source

Research on Optimization of Fe Clusters Structure Based on Structural Clustering Niche Differential Evolution Algorithm [PDF]

open access: yes, 2016
团簇被称之为“物质第五态”。它是材料科学的新起点,在许多领域都有着广泛的应用。团簇的稳态结构对其独特的物理和化学等性质起到了至关重要的作用,因而受到许多学者的广泛关注。由于团簇的大小在几埃到几百埃之间,尺寸非常小,用实验设备很难合成和直接观测。因此用理论研究的方法来探究团簇的稳态结构显得十分重要。但是寻找团簇的稳态结构十分困难,除了基态结构之外,还存在成千上万的亚稳态结构。目前团簇优化问题已被学者证明为NP难问题,因此用传统的优化方法难以获得最优解,于是使得基于进化算法的全局优化方法得到了广泛应用 ...
郑骥文
core  

Hobbyist preferences for pet freshwater turtles

open access: yesConservation Biology, EarlyView.
Abstract The burgeoning pet trade is a primary threat to wild freshwater turtles worldwide. Although the risks from commercial exploitation of turtles have been discussed widely, there is little empirical research on preferences for pet turtles from a hobbyists’ perspective.
Jingjing Zhao   +7 more
wiley   +1 more source

中国动物园大猩猩圈养种群现状分析

open access: yes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  

When and why to give shorebirds a head start

open access: yesConservation Biology, EarlyView.
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

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