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1.
栗斑腹鵐的栖息地和巢址选择   总被引:1,自引:1,他引:0  
高玮  王海涛  孙丹婷 《生态学报》2003,23(4):665-672
于 1 999到 2 0 0 1年 5月至 7月连续 3a在吉林省镇赉县大岗林场 ,采用样地法和样方法 ,对栗斑腹的栖息地选择和巢址选择进行了研究。结果表明 :此鸟的繁殖是在草甸草原 杏树环境下进行的 ,对栖息地样方和对照样方的对比分析得出 ,杏树最大高度、5 0 m半径圆内杏树数量、贝加尔针茅数量、大油芒数量、植物盖度、火绒草平均高度、贝加尔针茅最大高度、兴安胡枝子平均高度 8个因子是影响其栖息地选择的主要因子。通过对 46个巢的研究发现 ,大多数栗斑腹把巢建在贝加尔针茅下面 ,巢出入口方向多为东南 45°和西南 45°。对 46巢的 2 7个因子的主成分分析 ,结果发现植物盖度、火绒草高度、鸢尾数量、巢出入口方向、1 0 m内杏树数量、30 m内杏树数量、裸地面积这 6个因子是巢址选择的主要因子。对 46巢 2 6个巢址和非巢址因子进行判别分析 ,植物盖度、大油芒、乳浆大戟高度、石竹数量、线叶菊高度和 30 m内杏树数量等 6个因子 ,为巢位选择的主要因子。两种分析结果基本相似。总之 ,栗斑腹喜欢在植被盖度大、杏树相对多、贝加尔针茅和大油芒的密度大、食物资源丰富的区域内营巢。  相似文献   

2.
南充雉鸡的巢址选择和春夏季栖息地选择   总被引:1,自引:0,他引:1  
2006年3-6月,采用野外直接观察法和样方法,在四川省南充市太和白鹭自然保护区对雉鸡(Phasianus colchicus)的巢址选择和春夏季栖息地选择进行了研究。通过主成分分析和对比分析,巢址选择研究结果表明:雉鸡的巢都是选择在乔木盖度小、距水距离较近、草本高度和盖度都较大的白茅(Imperata cylindri-cal)干草丛中;影响雉鸡巢址选择的主要因子依次为:坡度、总盖度、乔木平均胸径、乔木盖度、郁闭度、距水距离、距路距离、灌木平均高度、巢周围干草比例、裸地面积、巢上方覆盖物厚、灌木盖度和巢所在草丛宽度等13个因子。春夏季栖息地选择研究结果表明:雉鸡在春夏季倾向于在植被总盖度大、坡度适中、乔木盖度适中、草本盖度和高度较大、灌木盖度较小、灌木高度较大、隐蔽度较大、距路距离较远和郁闭度较大等的生境栖息。  相似文献   

3.
2006年3—6月,采用野外直接观察法和样方法,在四川省南充市太和白鹭自然保护区对雉鸡(Phasianus colchicus)的巢址选择和春夏季栖息地选择进行了研究。通过主成分分析和对比分析,巢址选择研究结果表明:雉鸡的巢都是选择在乔木盖度小、距水距离较近、草本高度和盖度都较大的白茅(Imperata cylindrical)干草丛中;影响雉鸡巢址选择的主要因子依次为:坡度、总盖度、乔木平均胸径、乔木盖度、郁闭度、距水距离、距路距离、灌木平均高度、巢周围干草比例、裸地面积、巢上方覆盖物厚、灌木盖度和巢所在草丛宽度等13个因子。春夏季栖息地选择研究结果表明:雉鸡在春夏季倾向于在植被总盖度大、坡度适中、乔木盖度适中、草本盖度和高度较大、灌木盖度较小、灌木高度较大、隐蔽度较大、距路距离较远和郁闭度较大等的生境栖息。  相似文献   

4.
四川洪雅县赤腹松鼠巢址选择研究   总被引:2,自引:2,他引:0  
赤腹松鼠Callosciueus erythraeus在四川省洪雅县已经成为第一大森林害鼠.为了揭示赤腹松鼠巢址选择特征并为控制该物种的危害服务,2008年3~8月采取样线法对洪雅县赤腹松鼠的巢址选择状况进行了调查.共发现81棵巢树,对其巢位参数的统计显示,赤腹松鼠可在11种阔叶树和3种针叶树上营巢,对柏木Cpuressus funebris和楠木Phoebe zhennan有明显选择性,分别为营巢树数量的34.6%和33.3%.营巢树平均高度为18.6 m±0.6 m,巢距地面平均高度为16.2 m±0.5 m,巢位置一般靠近树的顶端,多朝东、南和东南方向,76.5%的巢位于树干与树枝的交界处.对无重复取样的巢址样方(n=65)和对照样方(n=65)中15个生境因子的对比分析表明,赤腹松鼠倾向在乔木平均高度较高、林下灌木盖度相对较高、坡度较大的生境中营巢.  相似文献   

5.
李乐  万冬梅  刘鹤  殷江霞  李其久  霍雅鹏 《生态学报》2011,31(24):7492-7499
杂色山雀(Parus varius)是一种分布区域极其狭窄的小型森林洞巢鸟类,种群数量稀少,在中国大陆仅见繁殖于辽宁省的东南部山区和毗邻辽宁的吉林省西南部山区,为当地留鸟.为了探讨巢址选择对杂色山雀繁殖的影响,找出影响杂色山雀繁殖成功率的巢址选择方面的主要因子,于2009-2011年3-7月,在辽宁省仙人洞国家级自然保护区通过悬挂人工巢箱,进行杂色山雀对人工巢箱的巢址选择以及不同的巢址对杂色山雀繁殖成功率的影响研究.研究表明:杂色山雀多在针阔混交林中活动和繁殖,对位于赤松与蒙古栎混交林中的巢箱有一定偏好.野外共发现24巢杂色山雀在人工巢箱中繁殖,其中15巢繁殖成功,9巢繁殖失败.对杂色山雀利用的巢址样方主成分分析表明,巢位因子( 19.826%)、乔木因子(17.571%)、灌木因子(13.11%)、光照因子(11.587%)、隐蔽因子(10.562%)和边缘效应因子(7.572%)是影响杂色山雀对人工巢箱选择的重要因子.利用巢箱与对照巢箱相比,两者在距水源距离、距路距离、乔木平均高度、灌木平均高度和植被类型这5个环境变量上存在显著差异.繁殖成功巢与繁殖失败巢相比,繁殖成功的巢箱所在位置距路稍远,坡度较高,乔木最大高度较高,灌木盖度略低于繁殖失败巢箱.人为干扰和天敌捕食是造成杂色山雀繁殖失败的主要原因.以上研究结果表明,巢向偏南、距地面2 m以上、周围乔木高大、灌木平均高度大于1.5m、盖度在45%-55%之间、距水源20 m左右、距路20 m以外的位于针阔混交林边缘的巢箱是杂色山雀繁殖的最优巢址.目前杂色山雀的种群数量还很稀少,希望本研究能对这一珍稀鸟类的保护提供重要参考.  相似文献   

6.
甘肃南部蓝马鸡的巢址选择   总被引:1,自引:0,他引:1  
蓝马鸡(Crossoptilon auritum)是我国特有的雉类,仅分布在青海东部、东北部,甘肃西北部及南部,四川西北部以及宁夏西部。2007和2008年在甘肃南部林区对蓝马鸡巢址进行了研究。在发现的12个蓝马鸡巢中,4巢(33.3%)在乔木下,4巢(33.3%)在岩石上或者岩洞内,2巢(16.7%)在枯枝下,2巢(16.7%)在灌丛下。U检验和T检验表明,坡位、坡度、灌木高度、灌木数量、灌木盖度、0.5m植被盖度、1.0m植被盖度、2.0m植被盖度、干扰度等9个生态因子在巢址(n=12)与对照样方(n=24)中存在显著差异。对13个变量进行逐步判别分析,结果显示,高坡位、高林下植被盖度及低干扰度是蓝马鸡巢址优先选择的生态因子。  相似文献   

7.
2013年7月和2014年5~7月,在新疆阜康地区对家麻雀(Passer domesticus)的巢址选择进行调查,以分析影响家麻雀巢址选择的生态因子。在研究区内共找到75个家麻雀的自然巢,筑巢生境为农田和防护林带,均在白杨(Populus adenopoda)林和胡杨(P.euphratica)林中的树上筑巢。其中,繁殖成功巢40个,繁殖失败巢20个,15个巢未记录到繁殖结果。在研究区内的居民房屋、墙洞等没有发现家麻雀的巢。采用逻辑斯蒂回归和主成分分析方法对筑巢地海拔(m)、筑巢树种、筑巢树高(m)、巢距路距离(m)、巢距地面高度(m)、巢上方盖度(%)、筑巢树胸径(m)、最近邻巢的距离(m)这些家麻雀的主要巢址参数进行分析,结果表明,影响新疆阜康地区家麻雀巢址利用的主要因素为巢距地面高度(m)、巢上方盖度(%)和巢距路距离(m)。对家麻雀繁殖成功巢(n=40)和繁殖失败巢(n=20)的巢址参数进行比较,两者差异不显著,因而推测,在研究区域的尺度内,家麻雀的巢址选择并不是影响其繁殖成效的主要因素。  相似文献   

8.
四川南充市夜鹭的巢址选择   总被引:1,自引:0,他引:1  
2006年3~6月,在四川省南充市太和保护区对夜鹭的巢址选择进行了研究。野外调查了夜鹭巢47个,对照样方26个,通过主成分分析和对比分析,表明影响夜鹭巢址选择的主要因子依次为:营巢树高度、植被平均高度、巢高、竹平均直径、隐蔽度、巢上方盖度、距水(西河)距离、距白鹭巢距离、植被盖度、巢下盖度。  相似文献   

9.
张洪海  王明  陈磊  刘松涛  窦华山  高东泉 《生态学报》2013,33(10):3233-3240
2010年和2011年3月-6月,对内蒙古达赉湖国家级保护区达赉湖西岸地区大鵟(Buteo hemilasius)的巢穴结构和巢址选择因子进行了调查研究.采用野外观察和样方法定位了13个大鵟巢址,并对巢址样方的20个生态因子进行测量,运用主成分分析法对影响大鵟巢址选择的主要因子进行了分析.测量显示,大鵟巢穴的基本结构特征为:外径(94.7+4.2) cm;巢高度(46.1±2.7) cm;内径(24.8±1.5)cm;巢深(14.0±+0.9)cm.生境因子分析结果表明,达赉湖西岸地区大鵟的巢集中分布在湖岸或水塘附近的悬崖,营巢点坡度为15°-45°之间的阳坡或半阳坡;隐蔽度高于20%;草本密度大于5株/m2;植被均高大于30cm;巢距悬崖上部距离2-5m;距水源l00m以内;距居民点距离大于lkm;距草原道路的距离大于0.5km;而对于物种丰富度没有特殊要求.主成分分析显示,影响大鵟巢址选择的主要因子有3个,依次为:隐蔽性因子(主要包括巢址区域的植物特征和地形特征)、干扰因子和食物因子.各主成分中,相对系数绝对值最高的变量依次是:植被盖度、距居民点距离、巢的高度和距草原道路距离.  相似文献   

10.
2006~2009年,通过点样方方法对斑背大尾莺Megalurus pryeri的巢址进行了研究,获得53个样本,拂子茅Calamagrostis epigejos是营巢生境的主要草本。拂子茅浓密(628根/m2)、芦苇稀疏(20根/1.5 m2)是斑背大尾莺典型的生境,巢高度较高(23 cm)。通过相关分析发现:巢高度和拂子茅总数、绿拂子茅数量显著正相关,但若控制水位、盖度及枯苇数等因素,相关性则不强;巢高度与拂子茅与灯心草等典型草本的高度正相关。进一步分析表明,活拂子茅数量与活苇数量及其他绿草数量负相关。有巢口与无巢口的样方中绿拂子茅数量无差异。对于大尾莺的保护,应该保护芦苇-拂子茅群落,注重芦苇与拂子茅等杂草的平衡。  相似文献   

11.
Evolutionary biologists have an array of powerful theoretical techniques that can accurately predict changes in the genetic composition of populations. Changes in gene frequencies and genetic associations between loci can be tracked as they respond to a wide variety of evolutionary forces. However, it is often less clear how to decompose these various forces into components that accurately reflect the underlying biology. Here, we present several issues that arise in the definition and interpretation of selection and selection coefficients, focusing on insights gained through the examination of selection coefficients in multilocus notation. Using this notation, we discuss how its flexibility—which allows different biological units to be identified as targets of selection—is reflected in the interpretation of the coefficients that the notation generates. In many situations, it can be difficult to agree on whether loci can be considered to be under “direct” versus “indirect” selection, or to quantify this selection. We present arguments for what the terms direct and indirect selection might best encompass, considering a range of issues, from viability and sexual selection to kin selection. We show how multilocus notation can discriminate between direct and indirect selection, and describe when it can do so.  相似文献   

12.
Stabilizing selection, which favors intermediate phenotypes, is frequently invoked as the selective force maintaining a population's status quo. Two main alternative reasons for stabilizing selection on a quantitative trait are possible: (1) intermediate trait values can be favored through the causal effect of the trait on fitness (direct stabilizing selection); or (2) through a pleiotropic, deleterious side effect on fitness of mutants affecting the trait (apparent stabilizing selection). Up to now, these alternatives have never been experimentally disentangled. Here we measure fitness as a function of the number of abdominal bristles within four Drosophila melanogaster lines, one with high, one with low, and two with intermediate average bristle number. The four were inbred nonsegregating lines, so that apparent selection due to pleiotropy is not possible. Individual fitness significantly increased (decreased) with bristles number in the low (high) line. No significant fitness-trait association was detected within each intermediate line. These results reveal substantial direct stabilizing selection on the trait.  相似文献   

13.
Selection ultimately entails differential reproductive success over several generations. This can be measured as a correlation of the number of progeny an individual has with the number of progeny its parent had. This correlation could have a genetic or a cultural basis. The effect of such a correlation is to multiply the single generation sampling variance (Vdeltap) in the diffusion approximation for fixation time by (1-b)+bx(1+r)/(1-r), where bxrn is the correlation between the number of progeny of an individual and its ancestor n generations ago (e.g., b is the heritability and br is the resultant parent-offspring progeny number correlation if the progeny number is genetically determined). This results in a reduction of the fixation or coalescent time by division by this factor. Sex differences in this correlation have been observed, and this provides an explanation for the difference of coalescent times of y-chromosomes and mitochondria.  相似文献   

14.
动物的性选择   总被引:2,自引:0,他引:2       下载免费PDF全文
有性生殖为个体之间设置了一个冲突和竞争的环境,因为雌雄个体都希望最大限度地把自己的基因传递给后代。性选择保证了动物的繁殖成功。性选择可以分为性别内选择和性别间选择。性别内选择促使动物格斗器官或其他有利于在格斗中获胜的一些特征得到发展;性别间选择促使用来吸引异性的一些特征得到发展。雌性动物的配偶选择或与所选择的特征协同进化,或可以从选择中得到直接的利益。  相似文献   

15.
Hierarchical expansions of the theory of natural selection exist in two distinct bodies of thought in evolutionary biology, the group selection and the species selection traditions. Both traditions share the point of view that the principles of natural selection apply at levels of biological organization above the level of the individual organism. This leads them both to considermultilevel selection situations, where selection is occurring simultaneously at more than one level. Impeding unification of the theoretical approaches of the multilevel selection traditions are the different goals of investigators in the different subdisciplines and the different types of data potentially available for analysis. We identify two alternative approaches to multilevel situations, which we termmultilevel selection [1] andmultilevel selection [2]. Of interest in the former case are the effects of group membership onindividual fitnesses, and in the latter the tendencies for the groups themselves to go extinct or to found new groups (i.e., group fitnesses). We argue that: neither represents the entire multilevel selection process; both are aspects of any multilevel selection situation; and both are legitimate approaches, suitable for answering different questions. Using this formalism, we show that: multilevel selection [2] does not require emergent group properties in order to provide an explanatory mechanism of evolutionary change; multilevel selection [1] is usually more appropriate for neontological group selection studies; and species selection is most fruitfully considered from the point of view of multilevel selection [2]. Finally we argue that the effect hypothesis of macroevolution, requiring, in selection among species, both the absence of group effects on organismic fitness (multilevel selection [1]), and the direct determination of species fitnesses by those of organisms, is untestable with paleontological data. Furthermore, the conditions for the effect hypothesis to hold are extremely restrictive and unlikely to apply to the vast majority of situations encountered in nature.  相似文献   

16.
17.
We show with a simulation that nonrepresentative sampling of two discrete fitness classes leads to biased estimates of selection. Systematic underestimation occurs if the selected class is overrepresented in the sample and overestimation if the unselected class is overrepresented. The bias is greater the stronger the selection intensity, the smaller the true fraction of individuals favored by selected, and the lower the sample size. We present a simple method that allows a posteriori statistical correction in cases of biased sampling given a separate estimate of the actual class representation, describe its practical implementation, and show that it works.  相似文献   

18.
Red deer hinds play a significant role in selecting stags for mating. We tested the hypotheses that in red deer ( Cervus elaphus ) the probability of becoming a harem holder (and hence achieving reproductive success) occurs in stags bearing larger, branched antlers and showing low fluctuating asymmetry (FA). Eleven antler characteristics were measured; absolute and relative FA were calculated on 51 cast antler sets from 19 individually recognized stags. Probability of becoming a harem holder (PBHH) was originally analysed separately, i.e. for antler size and FA of each antler characteristic and calculated factors for both antler size and FA. If analysed separately, large antler size and low relative but high absolute FA increased PBHH. When we combined antler size and FA of antler characteristics in one model using antler size and FA factors, however, PBHH and achieving reproductive success were mainly dependent on increasing antler size and enhanced antler branching rather than on FA. We conclude that in contrast to antler size, FA is unlikely to play any significant role in sexual selection as an indicator of individual quality.  © 2006 The Linnean Society of London, Biological Journal of the Linnean Society , 2006, 87 , 59–68.  相似文献   

19.
We estimated linear (β) and nonlinear (γ) selection gradients to quantify host plant‐mediated selection on the trait gall size in each of 22 unequally sampled subpopulations of the cynipid gall wasp Belonocnema treatae. We characterized the relationship between variation in subpopulation sample size and the magnitude of and the variance among selection gradients. We then tested the hypothesis that the intraspecific patterns we observed would follow two patterns that have emerged from published estimates of linear and nonlinear selection gradients compiled across species, namely that the average magnitude of β and γ and the variance among estimated β and γ decrease with increasing sample size. For both β and γ, intraspecific patterns of phenotypic selection in relation to sample size were not predicted by interspecific patterns. Thus, our results suggest that when selection is heterogeneous among subpopulations, variation in the biological basis for selection is more important in influencing estimates of selection than is variation in study size. Our study highlights the value of inspecting selection in relation to sampling effort at the level at which understanding the sources of variation in selection is most important, among populations within species.  相似文献   

20.
Fluctuating asymmetry (FA) has been suggested as a measure of the sensitivity of development to a wide array of genetic and environmental stresses. It has been also suggested that antlers in red deer could be important during social and rutting displays. We used antler measurements of 51 males that were measured over subsequent seasons, from 3–8 years of age, and analysed three antler traits: antler weight, length, and the number of antler tines (antler size). We calculated absolute and relative FA. All three size traits were highly significantly intercorrelated. By contrast to this, the FA of the three traits, did not show such relationships. With increasing age, antler size and FA also increased. When testing the repeatability of FA and antler size, there was a principal difference in the pattern between FA and antler size, with the latter being much more consistent than the former. This suggests that antler size, not FA, may be a good predictor of the bearer's quality in mate selection. This fits well with the good-genes hypothesis that the development of extravagant secondary sexual characters can be an honest advertisement of heritable male quality.  © 2007 The Linnean Society of London, Biological Journal of the Linnean Society , 2007, 91 , 215–226.  相似文献   

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