Results 31 to 40 of about 8,636 (191)

卡拉麦里山蒙古野驴的现状与保护

open access: yes野生动物学报, 2015
蒙古野驴(Equus hemionus)是国家Ⅰ级保护野生动物,被列入濒危野生动植物种国际贸易公约(CITES)附录Ⅰ中。卡拉麦里山自然保护区是蒙古野驴在我国种群数量最大的分布区,同时蒙古野驴也是卡拉麦里山自然保护区的主要保护动物,其种群数量和分布的变动反映着当地生态环境的变化。近年来,准东煤电煤化工产业开发在促进当地经济社会发展的同时,也给卡拉麦里山的野生动物带来了不利影响。通过路线调查和文献资料统计,比较了蒙古野驴种群数量及分布情况的历史变化,分析了卡拉麦里山蒙古野驴的栖息地现状 ...
彭向前
doaj  

The population dynamics and parameter of growth and mortality of Sillago sihama in the Minnan-Taiwan fishing grounds [PDF]

open access: yes, 2008
以2001~2003年在闽南-台湾浅滩渔场底拖网渔获物采集的多鳞鱚样品,进行渔获群体结构和生长与死亡的研究,并从生态学参数的变化探讨种群动态。结果表明,多鳞鱚渔获群体叉长范围65~237mm,优势组131~150mm,平均134.5mm,体重范围5~110g,优势组11~30g,平均26.1g。年龄范围0~3龄,优势组1龄,平均0.91龄。生长参数L∞为260.89mm、W∞为153.81g、k为0.6614、t0为-0.6158、tr为0.8474龄。Z为2.7728,M为1.3004,F为1 ...
卢振彬, 杜建国, 陈骁
core  

The collective application of shorebird tracking data to conservation

open access: yesConservation Biology, EarlyView.
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

Size structure and distribution pattern of Cyclobalanopsis glauca population in Evergreen Broad-leaved Forests(青冈常绿阔叶林中青冈种群结构与分布格局)

open access: yesZhejiang Daxue xuebao. Lixue ban, 2003
通过群落与种群的调查,对浙江北部几个地区的青冈常绿阔叶林中青冈种群的数量特征,从分株和分株+萌生枝两个层次上进行了研究.结果表明:青冈种群的大小结构在分株层次上,有两种类型:纺锤形结构和不典型的金字塔形结构(倒"J"型),在分株+萌生枝层次上,都为金字塔形结构;青冈种群主要是集群分布格局;动态分布格局是从集群分布到随机分布.
HUXiao-bing(胡小兵)   +1 more
doaj   +1 more source

Geographical Variation in Vegetative Growth and Sexual Reproduction of the Invasive Spartina alterniflora [PDF]

open access: yes, 2015
生物入侵是全球变化的重要内容,对全球经济和环境产生严重影响,并威胁生态系统的多样性。明确生物入侵发生的过程和机制可以有效地防控入侵生物带来的危害。繁殖是入侵种从定居到其后扩张过程中的一个重要的内在因素,进而可能影响入侵的成功。在入侵种扩散并占据广阔的地理分布区过程中,表型可塑性可能起到关键作用。揭示入侵种繁殖和表型可塑性在变异及其与环境因子的相关关系,对阐明外来物种的入侵机制和预测其分布具有重要的意义。互花米草原产美国大西洋沿岸和墨西哥湾,于1979年从美国引入中国。经过30多年的入侵和扩散 ...
刘文文
core  

Differences in characteristics between naturalized threatened plants and other threatened plants

open access: yesConservation Biology, EarlyView.
Abstract Many non‐native plant species introduced by humans have become naturalized. At the same time many species are threatened in their native range. However, the number of plant species threatened in their native range that are naturalized elsewhere remains unknown.
Weihan Zhao   +10 more
wiley   +1 more source

EFFECT OF ALEXANDRIUM TAMARENSE ON POPULATION DYNAMICS OF BRACHIONUS PLICATILIS [PDF]

open access: yes, 2005
采用单个体培养方法研究有毒赤潮藻塔玛亚历山大藻(Alexandriumtamarense)的细胞再悬浮液、细胞破碎液及其与亚心形扁藻(Platymonassubcordiformis)的混合藻液对褶皱臂尾轮虫(Brachionusplicatilis)实验种群动态的影响.结果表明,塔玛亚历山大藻及其细胞破碎液延缓了褶皱臂尾轮虫的生长发育,使轮虫的生殖前期延长,生殖期及寿命缩短,特定年龄出生率降低,产卵量减少,从而导致轮虫生殖力下降,种群增长受阻.其中以塔玛亚历山大藻细胞再悬浮液对轮虫的影响最为显著 ...
周立红, 王大志
core  

Representation of obligate groundwater‐dwelling copepod diversity in European protected areas

open access: yesConservation Biology, EarlyView.
Abstract Groundwaters sustain diverse surface ecosystems and are populated by metazoan species, mostly invertebrates, that provide fundamental ecological functions and are often of prominent conservation value due to narrow endemism and high phylogenetic rarity.
Francesco Cerasoli   +7 more
wiley   +1 more source

Investigation on population dynamics of Fejervarya multistriata in plantations of Fujian Province, eastern China. [PDF]

open access: yes, 2013
2011年6—9月和2012年4—5月,采用“围栏陷阱法“对福建省将乐县国有林场典型人工林内泽陆蛙种群进行调查,共捕获泽陆蛙222只。采用聚类分析方法,按照体长、体重将泽陆蛙划分为成体和亚成体,分析不同月份、不同类型人工林、不同林龄人工林内泽陆蛙的日均捕获量、肥满度和重长比的变化规律。结果显示:1)人工林泽陆蛙日均捕获量随月份变化先减小后增大,肥满度无显著变化,重长比先增大后减小。2)人工林泽陆蛙肥满度、重长比,混交林高于纯林;日均捕获量纯林高于混交林。3)随人工林林龄的增加泽陆蛙肥满度、重长比增大 ...
李劭抒   +4 more
core  

Effects of political identity activation and inaccurate metaperceptions on attitudes toward wolves

open access: yesConservation Biology, EarlyView.
Abstract Polarization between groups can undermine durable conservation outcomes. Activating group identities (i.e., an individual's sense of self derived from membership in a group) can exacerbate differences, especially when people hold inaccurate perceptions of their peers and rivals.
Alexander L. Metcalf, Justin W. Angle
wiley   +1 more source

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