Results 31 to 40 of about 7,934 (168)
对青海湖裸鲤55个个体Cytb基因全序列进行了测定和分析,探讨了种群结构和群体遗传多样性。用MEGA2.1软件分析了碱基组成和序列变异;以黄河花斑裸鲤为外群,构建了单倍型的NJ树;用Arlequin Ver.2 000程序计算了群体内遗传变异值(Fst)。结果显示,青海湖裸鲤群体没有显著的种群结构,提示青海湖裸鲤群体内存在广泛的基因交流;种群的遗传多样性较低(π=0.7828±0.0532),青海湖裸鲤种群很可能在历史上遭受过严重的“瓶颈效应”
何舜平, 彭作刚, 李俊兵, 赵凯
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Abstract Despite the crucial role of human impacts on biodiversity loss, many assessments of this loss focus on single metrics, such as species richness, and overlook the multidimensional effects of human activities. Because of its importance to ecosystem functioning, we investigated the functional diversity of medium‐ and large‐sized mammal ...
Xueyou Li +8 more
wiley +1 more source
绿孔雀(Pavo muticus)是备受关注的濒危物种。我国南方曾广泛分布的云南亚种(P.m.imperator)目前收缩到中部、南部和西部的局部地区,近年来陆续开展了野外种群调查,但遗传多样性的分析和评估尚未开展。本研究利用从玉溪市新平和峨山交界处采集的野外绿孔雀自然脱落的羽毛,采用11对微卫星标记分析遗传多样性和结构,并与国内主要圈养种群(建群者来自瑞丽地区和其他未确定的地点)进行比较。结果表明:该野生种群的遗传多样性较低,受到近交的影响,遗传多样性进一步丢失的风险较高。遗传结构上 ...
刘思霞 +8 more
doaj
Diversity of heavy-metal resistant microorganisms in the hydrothermal sulfide of the Eastern Pacific Ocean and the microbial community structures of the surface seawater across the South Mid-Atlantic Ridge [PDF]
本文通过微生物分离培养和非培养的方法,分析了东太平洋热液烟囱硫化物中重金属抗性微生物的多样性,并对其中一株锌抗性菌株的抗性机制进行了初步研究;同时,详细解析了南大西洋跨洋中脊表层海水中微生物的种群结构。 第一部分:东太平洋热液烟囱硫化物中重金属抗性微生物的多样性 重金属污染对生态系统和人类健康都构成了巨大威胁,而微生物能通过多种机制对环境中的重金属进行吸附和去除。研究和分析深海热液区多金属硫化物中重金属抗性菌的种群结构及其抗性机制,将为重金属污染生物的修复提供参考。本研究利用七种含有不同种类重金属 ...
谢燕荣
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Relationship Between Soil Factors and Enzyme Activities in Mangrove Wetland of Dongzhai Port [PDF]
[Objective] Mangroves are part of a wetland ecosystem found along tropical and sub-tropical coastlines. The soil active organic carbon composition, soil enzyme activity, and the interaction between them, under different plant community conditions was ...
Chen Xiaohua +4 more
core +1 more source
Abstract Constructed value of information (CVoI) is an expert elicitation decision‐analytic tool used to prioritize sources of uncertainty based on their potential to improve decision outcomes if resolved. Despite increased application of CVoI, the robustness of CVoI prioritization of sources of uncertainty relative to differences in expert elicitation
Kristin P. Davis +7 more
wiley +1 more source
1983—1984年,测定了东湖水柱总沉降颗粒有机物中的碳、氮、磷、叶绿素a含量和浮游动物数量,以及该湖浮游动、植物优势种的干重/湿重、C/N及C/P比值。利用所得数值计算出其颗粒有机碎屑的沉降速率。东湖这两年的颗粒有机碎屑的沉降速率[g/m~2·a),Ⅰ站分别为10.67与10.97(碳),2.15与2.68(氮)及0.29与0.30(磷);Ⅱ站分别为10.35与7.26(碳),2.17与1.12(氮)及0.22与0.16(磷)。与水柱浮游植物净生产量相比 ...
林婉莲,刘鑫洲
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Abstract Human development is a driver of global change and a major threat to biodiversity. Protected areas maintain and support biodiversity, but outside stressors, such as climate change and land use change, can negatively influence natural resources within protected areas.
Leah J. Rudge +2 more
wiley +1 more source
2019年7月—2020年12月对广东树木公园的鸟类多样性进行调查,对公园内鸟类物种群落结构的动态变化进行了分析。结果表明:公园内分布有繁殖鸟类13目37科81种,其中国家二级重点保护鸟类6种,广东省重点保护鸟类8种;调查的81种鸟类中,优势种3种,常见种15种,稀有种29种,罕见种34种;东洋界鸟类和留鸟占优势;树木公园鸟类多样性存在季节性差异:种类和数量、多样性指数9—12月逐渐上升。树木公园内鸟类群落结构反映了城市森林公园在维持鸟类多样性,以及充当迁徙鸟类的“踏脚石”发挥了重要的作用。
郭乐东 1 #孙松 1 +1 more
doaj
Diversity, geographical distribution and seasonal variation of Skeletonema (Bacillariophyta) in the coastal waters of China [PDF]
骨条藻(Skeletonema)是一类广泛分布的浮游硅藻,大量繁殖可引起赤潮和水华。以往对我国近海骨条藻的研究,绝大多数都是以中肋骨条藻(S.costatum)为主,种类单一,且研究的地理范围和季节性不够全面和系统,对其生态特征尚不明确。 本研究从2013年10月至2015年1月按每个季度对渤海、黄海、东海和南海四大海域的七个站点进行水样采集,应用光学显微镜和电子显微镜技术对分离纯化的株系和固定样品进行了形态学观察和细胞计数。共鉴定出9种骨条藻,分别为热带骨条藻(S.tropicum),曼氏骨条藻(S ...
刘洋
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