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11.
Abstract.  1. A mark–recapture study was conducted on the American Apollo butterfly Parnassius clodius Menetries during three field seasons (1998–2000) to examine its movement patterns over the course of a season within a sagebrush meadow in Grand Teton National Park, Wyoming, U.S.A. The study examined how resources affected butterfly distribution patterns and used mark–recapture data to gain insight into movement differences between sexes and over time.
2. The average straight-line movement of P. clodius was 202 m day−1, adjusted for sampling effort at different distances. Movement estimates in all 3 years were highly correlated with the average distance between plots sampled.
3. Butterfly abundance was correlated positively with per cent cover of its host plant Dicentra uniflora , but this relationship decreased in importance during the peak of the flight period when individuals may be more interested in finding mates. There was a weak, positive correlation between butterfly abundance and the abundance of its primary nectar source, Eriogonum umbellatum in 1999, but no relationship in 2000.
4. Survival, recapture, and transition probabilities were estimated using open population, capture–recapture models. Survival and recapture probability decreased over the course of each season, while the probability of moving between plots increased. Recapture probability was significantly lower for females than for males among all 3 years, but there was no difference between the sexes in survival rate.  相似文献   
12.
The population sizes and range of Parnassius apollo started to decline in Finland in the 1930s and resulted in complete extinction in many parts of its former range 30 years later. It has been suggested that metal pollution is one potentially very important reason for the decline. Recently, a recovery of P. apollo and widening of its range has started in the southwestern Finland, simultaneously with a decline in metal fallout from air. Metal analyses were performed with larval and host plant samples collected from an area where P. apollo is recolonising its former range (the archipelago between the island of Kemiö and the Hankoniemi peninsula). In the host plants (Sedum telephium), the level of Fe was significantly lower and the levels of Cd and Zn suggestively lower in the current range (n = 35) of P. apollo than in the former range (n = 12). Analyses on larvae of P. apollo (n = 29) showed lower levels of Cd, Fe and Mn than in the host plant leaves. The excretion of these metals, as well as Zn, via the faeces was effective. The level of the Cd-antagonist Cu was considerably higher in caterpillars than in the food. When caterpillars were fed with metal-polluted food from Helsinki city (4.35ppm Cd/dwt; n = 5) they died, whereas control individuals fed with food from the archipelago (2.49ppm Cd/dwt; n = 5) survived. These results indicate that metals may play an important role in the large-scale decline and partial recovery of P. apollo in the western Europe.  相似文献   
13.
绿孔雀(Pavomuticus)在世界共3个亚种,其中P.muticusimperator主要分布于我国云南、缅甸东部、泰国和印度等地[1~3]。三十多年前,在西双版纳的大部分地区均有该种的分布,是有名的“孔雀之乡”[4]。随着人类经济活动的影响,云...  相似文献   
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我们于2007年3-4月和10-11月在云南元江上游石羊江河谷绿孔雀(Pavo muticus imperator)的分布区内, 采用样线法和样方法调查了绿孔雀的觅食生境, 测定了21个生态因子。结果表明, 春季的觅食地利用样方距小路距离、乔木种类和藤本密度与对照样方存在显著差异, 而秋季的则不显著。生态因子比较和逻辑斯谛回归分析结果表明, 春、秋季绿孔雀均选择落果多、接近水源、坡度小、乔木的盖度和胸径大的地区作为觅食地。乔木和草本盖度, 距小路、居民点和林缘距离等是影响判别春、秋季觅食地选择的关键因子。概率和空间分布分析结果表明, 春、秋季绿孔雀在研究区内的概率分布呈明显的斑块状, 不同季节觅食活动位点均趋向于聚集分布, 分布区存在分离, 但有部分重叠。生态因子的主成分分析结果表明, 人为干扰对绿孔雀的影响大于安全和食物需求对它们自身的影响。隐蔽条件、食物和水源等关键性生态因子的配置和可获得性决定了绿孔雀的觅食地选择行为, 它对觅食地利用的不均匀是由于可利用资源分布不均匀所致, 而人为干扰压缩了可利用的适宜生境, 降低了利用程度。  相似文献   
15.
于非  王晗  王绍坤  张强  季荣 《生态学报》2012,32(19):6203-6209
局部气候变暖可能改变适应低温环境物种的分布格局,迫使该物种向高海拔或高纬度地区迁移,导致喜寒的山区物种适生区变小、种群数量减少甚至灭绝。阿波罗绢蝶(Parnassius apollo L.1758)属喜寒物种,在国内仅分布于新疆,且天山西部是其主要分布区。根据近40 a阿波罗绢蝶种群数量及垂直分布调查,结合研究区域——天山西部的果子沟山区的气象资料,采用相关函数分析近40 a来阿波罗绢蝶数量与分布对研究区域温度变化的响应。结果表明:1)研究区域的阿波罗绢蝶种群数量明显下降,2010年种群数量不及1981年的50%,且具有明显的垂直分布特征,80.4%的阿波罗绢蝶集中分布于1600—2100 m的山区,并有向高海拔迁移趋势;2)近40 a研究区域增温趋势显著,冬季增温最为明显,每10 a增温速率为0.350℃;3)阿波罗绢蝶数量与冬季和春季平均温度的相关系数最大,分别为-0.79、-0.77,表明越冬期和孵化期温度对阿波罗绢蝶数量有显著影响;4)滑动序列相关分析表明,阿波罗绢蝶数量对冬季和2月份平均温度变化的响应较明显,随着冬季温度及早春2月份温度升高,负相关系数有增加趋势,说明阿波罗绢蝶在长期进化过程中已适应低温山区环境,冬季温度偏高和早春温度迅速回升都将不有利于阿波罗绢蝶越冬和胚胎发育。  相似文献   
16.
【目的】分析中国冰清绢蝶Parnassius glacialis遗传多样性和遗传分化情况及其系统发生关系,推测其起源及分歧时间,并探讨其历史生物地理分布格局的成因。【方法】以2008-2016年采集于中国13个地区的冰清绢蝶的325头及绢蝶属其他11个种的11头个体样品,对其线粒体基因组的AT富集区(控制区)序列进行PCR扩增和序列测定,采用MEGA 6.0, Dna SP 5.1和Arlequin 3.5等软件分析其遗传多样性和遗传分化情况;以其他近缘绢蝶种类作为外类群,采用PhyML3.0, MrBayes 3.2和BEAST V1.8.3等软件重建冰清绢蝶的系统发生树,并利用宽松分子钟和校准方法推测中国冰清绢蝶的起源和分歧时间;同时结合现今冰清绢蝶的地理分布特点和第四纪以来的地球环境事件,分析其扩散路径,探讨其历史生物地理分布格局及成因。【结果】冰清绢蝶AT富集区序列长度介于487~495 bp之间,平均为491 bp,其长度的差异主要体现在Poly(T)或Poly(A)的数目差异,A+T平均含量为95.76%。供试冰清绢蝶13个地理居群325头个体中,共检测出基于线粒体基因组AT富集区序列的239个单倍型,单倍型多样性Hd为0.9971;核苷酸多态性指数π值为0.02948, Theta (per site)Eta值为0.06594。系统发生分析和分子定年显示,冰清绢蝶和白绢蝶P.stubbendorfii为近缘姊妹种,二者在距今7.52百万年(Ma)的中新世晚期开始分化。冰清绢蝶的祖先可能起源于我国西南地区(现今横断山脉-喜马拉雅附近的青藏高原东北缘)距今1.53 Ma的更新世时期,先由起源地先期扩散到达小陇山、秦岭一带;后来,由于第四纪的冰期-间冰期轮回事件和扩散路径的不同而分化出2大支系,但两个支系之间存在少量的单倍型相互混杂现象;随后,2大支系继续向低海拔、低纬度地区扩散,即通过伏牛山脉向东北方向扩散到嵩山、泰山、昆嵛山一带,经大别山系向东南方向扩散到琅琊山、紫金山和天目山一带。【结论】中国13个居群的冰清绢蝶没有形成明显的地理分化格局,其遗传变异主要来自居群内部,居群间的遗传分化现象尚不明显;冰清绢蝶起源于更新世时期的较高海拔地区,由于第四纪的冰期-间冰期轮回事件以及扩散路径的不同而形成2大支系并向中国东部和南部低海拔和低纬度地区扩散。  相似文献   
17.
 A rare deep-sea ophidiid genus Mastigopterus known to contain two species, M. imperator Smith and Radcliffe, 1913 and M. praetor Smith and Radcliffe, 1913, was reviewed on the basis of six specimens including the holotypes of both species. Dorsal and anal fin ray counts and the size of cephalic sensory pores previously thought to be diagnostic characteristics to discriminate the two species did not suggest the presence of two forms, the large (M. imperator) and the small species (M. praetor), in the genus. Apparently the genus is represented by a single species, M. imperator, known from off Madagascar, the East and South China Seas and Papua New Guinea. Received: September 7, 1999 / Revised: July 9, 2001 / Accepted: November 13, 2001  相似文献   
18.
Abstract  1. Many butterfly populations persist in networks of naturally fragmented habitat patches. Movement and reproductive decisions made by adult females are critical to the persistence of these populations because colonisation of extinct habitat patches in the network requires emigration of fecund adult females from their natal meadow and their subsequent establishment in the extinct patch.
2. Movement and oviposition behaviours of mated Parnassius smintheus females released in suitable meadows (a good- and a poor-quality meadow) and an unsuitable meadow were compared, to determine whether adult females consider meadow suitability for their offspring despite frequent oviposition events off the larval host plant.
3. Bootstrap and correlated random walk analyses of female step lengths and turn angles demonstrated that females flew more randomly in the unsuitable meadow than in the suitable meadows. Although females tended to turn the sharpest angle between landing sites in the good-quality meadow, and fly the smallest distance between landing sites and displace the smallest distance from the release site in the suitable meadows, no significant differences were detected in turn angle, step length, and dispersal rates between suitable and unsuitable meadows.
4. Results from female flight observations and a caged oviposition study suggest that females lay significantly more eggs in suitable habitat than in unsuitable habitat despite not ovipositing on the host plant, and support the above findings.
5. Movement and oviposition behaviours of adult female P. smintheus promote their retention within meadows that can support their offspring.  相似文献   
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