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1.
本文作者于1982—1988年在山西庞泉沟国家级自然保护区对褐马鸡(Crossoptilon mantchuri-cum)的种群数量进行了调查。结果种群密度为0.077(只/公顷),A、B、C垂直带间的数量分别为0.091、0.093、0.048,各占种群数量的39.22%、40.09%和20.69%,D带经调查,尚未见有分布。在繁殖前的5月为种群数量最低基数(0.030只);繁殖后的7月数量最高(0.099只)。  相似文献   

2.
山西五鹿山褐马鸡不同季节的空间分布与栖息地选择研究   总被引:19,自引:0,他引:19  
1997~1998年在山西省五鹿山自然保护区内对世界珍禽褐马鸡(Crossoptilon mantchuricum)越冬期与繁殖期的空间分布模式及其变化规律进行了研究,同时探讨了种群空间分布模式与栖息地结构特征之间的关系。经Pois—son函数和χ^2检验,发现褐马鸡在越冬期和繁殖期均为聚集分布,但越冬期的聚集程度更为明显。通过对栖息地可利用率与实际利用率的比较,发现褐马鸡在越冬期与繁殖期对栖息地的利用存在显著性差异:越冬期褐马鸡对阔叶林具有明显的负选择性;进入繁殖期后,褐马鸡对落叶阔叶林和灌丛的利用率显著增加,而对针叶林和针阔混交林的利用率有所减少。对两个时期的栖息地样方进行判别分析,发现草本植物数量、草本植物平均高度、乔木胸径、乔木高度是影响褐马鸡越冬期与繁殖期栖息地选择的主要因子。研究结果表明,褐马鸡种群的空间分布模式及其变化,与栖息地结构以及空间资源分布的季节性变化有关。在越冬期,由于温度、降雪等气候因素的影响,草本植物都已枯萎,落叶阔叶林的郁闭度较低,隐蔽条件较差,褐马鸡活动的区域范围受到一定的限制,此时褐马鸡常常在郁闭度较高的针叶林或针阔混交林中,并聚集形成较大的群体,共同取食,聚集分布的程度较高;进入繁殖期后,随着落叶阔叶林郁闭度增大以及林下、灌草丛中草本植物种类和数量的增多,褐马鸡群体逐渐变小,多以配偶对的形式活动,空间聚集程度降低。但由于褐马鸡对栖息地具有严格的选择性,许多配偶对主要集中在质量较好的区域内占区和营巢,因此在大尺度上褐马鸡种群的空间分布仍为聚集型分布。  相似文献   

3.
B 《动物学报》2005,51(4):586-597
1999年,2000年和2002年,在西藏西北部的西藏羌塘自然保护区分别沿三条横跨该自然保护区的长度为750-860km的东西向样线估计了藏羚(Pantholopshodgsoni)、藏野驴(Equuskiang)和藏原羚(Procaprapicticaudata)密度(每平方公里个体数)和遇见率(每平方公里遇见个体数)。在低海拔(4500-4700m)地区,藏羚、藏野驴和藏原羚数量很少,在那些人类活动强度高或中等的地区,藏羚、藏野驴和藏原羚的数量也极少,以致无法估计密度或遇见率。在高海拔(4700-5200m)地区,藏羚和藏野驴数量在那些人类和家畜活动强度低的地区,数量总比那些中等人类活动强度的地区高,尽管藏羚的数量差别比藏野驴小。藏原羚的情形不一样,在人类活动强度低或中等的地区的遇见率相仿。在某种程度上,这种差别可能与这些动物的生境偏好有关。看起来,藏原羚、其次是藏野驴比藏羚更能耐受人类和家畜的活动。注意到这三种动物在人类和家畜活动低的地区的结果方差都大,表明三种动物在有人类和家畜活动低的地区与在那些中等人类和家畜活动地区的分布相反的成群分布。三年中有蹄类动物遇见率的模式都相似,在调查期间有蹄类动物种群没有波动的趋势  相似文献   

4.
栖息地特征对褐马鸡种群密度和集群行为的影响   总被引:4,自引:0,他引:4  
1998-2000年冬季在山西芦芽山自然保护区选择车道沟和梅洞 2个研究地,就栖息地特征对褐马鸡 (Cros soptilonmantchuricum)越冬种群密度和集群大小的影响进行了研究。经χ2 检验,针叶林是褐马鸡冬季经常利用的栖息地类型。对 2个研究地的栖息地结构比较发现,车道沟适宜栖息地的面积较梅洞大,连接性也较好,褐马鸡种群有更为广阔的取食空间和更多的隐蔽场所,而且活动的阻碍也较小;而梅洞栖息地的取食空间较小,隐蔽场所较少,其活动时受到的阻碍也较大。从 2个研究地微生境结构特征的差异,并结合褐马鸡越冬期栖息地选择来看,树高和高层盖度对褐马鸡在 2个栖息地的选择上起重要作用。车道沟乔木较粗大,不但有丰富的食物,而且可提供较好的夜宿条件;高层盖度越大,栖息地的隐蔽条件越好,能吸引更多的褐马鸡个体取食和越冬。研究结果表明,栖息地结构连接性、微生境结构特征的差异以及人为干扰是褐马鸡种群密度和集群行为差异的主要影响因素。  相似文献   

5.
查清新疆东部哈密山区野生天山马鹿(Cervus elaphus songaricus)种群的现状,可为有效保护与合理利用野生马鹿资源提供科学依据。我们通过截线抽样法和遥感技术,弄清哈密山区天山马鹿的栖息地范围,估算马鹿的种群数量及种群密度。在哈密山区野生天山马鹿分布区域共设计了28条样线,总长度60.1 km,遇见马鹿233头,通过计算得到该地区马鹿天山亚种种群平均密度为(2.83?1.01)头/km2。栖息地面积374.35 km2,估计马鹿总数为(1 057.56?379.71)头左右。雌雄比例2.24:1,幼体和亚成体的总数量多于成体和老体总数。研究区域内马鹿的种群密度和资源总数量比往年的调查结果有所上升;马鹿的分布海拔高度比较一致,但种群的大小具有不均匀性;从性比和年龄结构来看该研究区域的马鹿种群面向着数量的增长趋势。  相似文献   

6.
莫莫格自然保护区白鹤秋季迁徙停歇期觅食生境选择   总被引:1,自引:0,他引:1  
2008年秋季(10月8日—20日)及2009年秋季(9月20日—10月16日),通过样方法对觅食生境11个生态因子进行调查,利用卡方检验、资源选择指数和资源选择函数在莫莫格保护区对秋季迁徙停歇期白鹤觅食生境选择进行研究。结果表明,白鹤对距人为干扰源距离、植被密度、盖度、高度、植物性食物密度以及水深均具有选择性,但对宏观尺度干扰因子的选择性较低。其偏好觅食生境的特点为:距一级路>5000m,>二级路1500m以上,>三级路1000m以上,>居民点1000m以上,农田>1000m;植被密度20~50株/m2,盖度<10%,高度<20cm,扁杆藨草密度1~50株/m2,藨草密度1~10株/m2,水深40~60cm。白鹤秋季觅食生境资源选择函数为Logistic(P)=0.663+0.565×与一级道路距离+0.042×与二级道路距离+0.519×与三级道路距离+0.353×与居民点距离+0.169×与农田距离–0.455×植被密度–0.618×植被盖度–0.548×植被高度–0.158×扁杆藨草密度–0.404×藨草密度+0.920×水深,T(x)=eLogistic(p)/[1+eLogistic(p)],模型正确预测率为82.9%。  相似文献   

7.
贺兰山岩羊的数量与分布   总被引:5,自引:0,他引:5  
2003年11~12月,采用样线调查法对贺兰山东坡(宁夏贺兰山国家级自然保护区)和西坡(内蒙古贺兰山国家级自然保护区)境内岩羊(Pseudois nayaur)种群的数量与分布进行了调查。共记录岩羊实体141群746只。在宁夏贺兰山国家级自然保护区和内蒙古贺兰山国家级自然保护区范围内均有岩羊分布,但东坡岩羊的平均群大小为6·03只,西坡为3·24只;东坡的遇见率为0·32只/km,西坡的遇见率为0·19只/km。卡方检验表明,贺兰山东、西坡的平均群大小和遇见率均存在极显著差异,东坡是岩羊的主要分布区。利用DISTANCE5·0软件估计贺兰山东坡岩羊的密度为5·144只/km2,种群数量为10611只;西坡的密度为2·532只/km2,种群数量为1714只;整个贺兰山地区岩羊的估计密度是4·445只/km2,种群数量为12178只。  相似文献   

8.
于2003年5月~2004年11月,采用标志重捕法对栖息在生态保留带的普通田鼠种群结构和数量动态进行了跟踪研究。结果表明,两年中种群密度夏季最大分别达到410个体/hm2和641个体/hm2,春季最少分别达到166个体/hm2和153个体/hm2,种群数量从7月份开始增长,8月份种群密度减少并于11月份开始重新增长。种群中雌性个体数量比较多,雌性在种群中的居留时间较长,同时存活率比雄性高,这导致种群数量的季节变化。种群周转率比较高,在两个捕鼠期间种群中的80%个体被更新,这表明普通田鼠在生态保留带中的活动非常频繁,不断与周围的其他种群进行交流,提高了种群对环境的适应能力。种群中雌雄个体的巢区之间没有年间变化,活动巢区比较小,巢区长度2003年平均为11 m,最长为37.5 m,2004年平均为13 m,最长为52 m。Pearson相关指数表明种群数量和生态保留带年龄、覆盖率和高度之间没有相关性。  相似文献   

9.
高原鼠兔洞穴系统的恢复是其种群恢复的关键指标之一,洞穴分布的变化可以反映种群的动态。本研究于2014-2016年在青海省祁连县对2.79 hm2高寒草甸内高原鼠兔(Ochotona curzoniae)种群密度、洞穴密度和洞穴的相对位置进行跟踪观测。其中包括6个50m×50m 的灭鼠堵洞处理、6个30m×30m 的灭鼠处理和3个50m×50m的对照处理。分别采用平均最近邻指数和平均拥挤度指数分析洞穴系统中有效洞、弃洞、粪坑和嬉戏坑的分布模式及洞系表现面积,并对各参数进行描述性和相关性分析。结果显示:高原鼠兔种群密度恢复过程中(1)有效洞的空间格局由随机向离散分布转变,弃洞由随机向聚集分布转变,粪坑和嬉戏坑无明显变化趋势;有效洞和弃洞分布格局的恢复都朝向灭鼠前状态,但恢复的都不充分;(2)有效洞最近邻指数与其自身密度正相关;弃洞最邻近指数与其自身密度负相关;粪坑、嬉戏坑最近邻指数与其自身密度无显著相关性;其中,仅粪坑的分布最近邻指数与高原鼠兔种群密度呈显著负相关;(3)有效洞与粪坑、嬉戏坑表现面积的变化情况较为一致,与弃洞呈互补态势;洞系表现面积的变异性远小于洞穴密度。结果说明:(1)高原鼠兔洞穴分布格局和洞穴密度的恢复具有滞后性;(2)有效洞、弃洞的分布格局主要受洞穴密度的影响;(3)高原鼠兔种群的恢复过程中对洞系面积的需求优先于洞口数量。  相似文献   

10.
长岛海域是黄渤海东亚江豚(Neophocaena asiaeorientalis sunameri)的热点分布区域之一。为了掌握长岛海域东亚江豚的种群密度与分布特征,2019年10月至2021年10月采用截线抽样法进行了5次东亚江豚目视考察。5次考察总航程2 421 km,共发现东亚江豚614次,1 156头次。相同月份调查种群遇见率无显著性差异(P> 0.05),不同月份种群遇见率差异极显著(P <0.01),提示东亚江豚种群在该水域可能存在季节性迁移。按照考察月份对数据进行合并处理,长岛海域5月和10月东亚江豚平均种群密度为(0.56±0.11)头/km2(0.46~0.68头/km2)和(3.63±0.25)头/km2(3.38~3.88头/km2),平均种群数量为(20 209±202)头和(2 971±681)头,这在目前已知所有东亚江豚分布区中是最高的。尽管不同季节种群数量差异显著,但东亚江豚种群在长岛海域的空间分布特征相似,砣矶岛-大钦岛西北侧和东南侧均为高密度分布区,因此...  相似文献   

11.
Li H  Yue B  Lian Z  Zhao H  Zhao D  Xiao X 《Zoological science》2012,29(9):593-598
A detailed understanding of the habitat needs of brown eared pheasants (Crossoptilon mantchuricum) is essential for conserving the species. We carried out field surveys in the Huanglong Mountains of Shaanxi Province, China, from March to June in 2007 and 2008. We arrayed a total of 206 grid plots (200 × 200 m) along transects in 2007 and 2008 and quantified a suite of environmental variables for each one. In the optimal logistic regression model, the most important variables for brown eared pheasants were slope degree, tree cover, distance to nearest water, cover and depth of fallen leaves. Hosmer and Leweshow goodness-of-fit tests explained that logistic models for the species were good fits. The model suggested that spring habitat selection of the brown eared pheasant was negatively related to distance to nearest water and slope degree, and positively to cover of trees and cover and depth of fallen leaves. In addition, the observed detected and undetected grids in 2007 did not show significant differences with predictions based on the model. These results showed that the model could well predict the habitat selection of brown eared pheasants. Based on these predictive models, we suggest that habitat management plans incorporating this new information can now focus more effectively on restrictions on the number of tourists entering the nature reserve, prohibition of firewood collection, livestock grazing, and medicinal plant harvesting by local residents in the core areas, protection of mixed forest and sources of the permanent water in the reserve, and use of alternatives to firewood.  相似文献   

12.
秦岭北坡雉类种群密度和群落结构的初步研究   总被引:4,自引:0,他引:4  
本研究将秦岭北坡周至自然保护区划分为4个生态地理类型带,在以Gates截线法调查雉类种群密度的基础上,对不同生态地理类型雉类群落结构进行了研究。结果表明,秦岭北坡雉类的物种多样性与植被和海拔有一定关系,环境的稳定性对雉类物种多样性有着一定影响。调查中还发现红腹锦鸡已分布到海拔2700 m的山坡上。  相似文献   

13.
艾怀森 《动物学研究》2006,27(4):427-432
根据高黎贡山地形和气候变化,将其分为南、中、北三段。通过查阅文献、访谈和野外调查,在该地区共记录到21种雉类。分布在海拔2500m以上的仅有9种,占45%;在海拔2500m以下的地域分布有雉类17种,占85%。北段有雉类13种,中段有11种,南段有12种。其中北、中、南段均有分布的仅有3种,北段和中段共有种为9种,中段和南段共有种为5种,北段和南段共有种也是5种。结果表明雉类多样性随海拔升高而降低,北段高于南段。生境破坏与狩猎是该区雉类生存的主要威胁因子。加强管理,恢复和建立生境走廊,加强宣传教育和执法力度以及开展观鸟旅游,可使该区雉类得到更好的保护。  相似文献   

14.
Li H Q  Lian Z M  Chen C G 《农业工程》2009,29(6):335-340
The foraging habitat selections of brown-eared pheasant (Crossoptilon mantchuricum) and the common pheasant (Phasianus colchicus) were studied in Huanglongshan Nature Reserve Shaanxi, China. Foraging habitat characteristics were measured on the basis of expected differences between species at 183 sites from November to December 2006 and January 2007. The results showed that both species selected foraging habitats with altitude (<1200 m), conifer forest, half sunny and half shady slope, sunny slope, density of trees (<5 individuals/100 m2), cover of shrub (>50%), visibility class (<10%) and distance to water source (<300 m). However, the brown-eared pheasant selected habitats with cover of trees (30–50%), middle or lower slope location, distance to edge of woods (<300 m) and human disturbance (<500 m), and the selection on density of shrub was not observed, compared to the selections on cover of trees (<30%), lower slope location, distance to edge of woods (<500 m) and human disturbance (<300 m), and density of shrub (>500 individuals/100 m2) for common pheasant. We also found that the common pheasant avoid predators by concealment whereas brown-eared pheasant evade predations by running away strategy.  相似文献   

15.
两种锦鸡和环颈雉线粒体DNA(mtDNA)的比较研究   总被引:15,自引:3,他引:12  
张亚平  陈欣 《动物学研究》1991,12(4):387-392
本文以10种限制性内切酶分析雉科中环颈雉,红腹锦鸡和白腹锦鸡线粒体DNA(mtDNA)。雉属与锦鸡属之间的遗传距离P为0.076(0.067-0.085),红腹锦鸡与白腹锦鸡的P为0.012。推算雉属和锦鸡属的分化大约发生在3.8×10[6]年以前,红腹锦鸡与白腹锦鸡的分化大约在6×10[5]年以前。这些结果表明:1.在雉科系统发生中,雉属与锦鸡属是近缘的属;2.红腹锦鸡和白腹锦鸡的分化较晚,关系密切,可能只是两个亚种。  相似文献   

16.
The phylogenetic relationships of 21 pheasant and 6 non-pheasant species were determined using nucleotide sequences from the mitochondrial cytochrome b gene. Maximum parsimony and maximum likelihood analysis were used to try to resolve the phylogenetic relationships within Phasianidae. Both the degree of resolution and strength of support are improved over previous studies due to the testing of a number of species from multiple pheasant genera, but several major ambiguities persist. Polyplectron bicalcaratum (grey peacock pheasant) is shown not to be a pheasant. Alternatively, it appears ancestral to either the partridges or peafowl. Pucrasia macrolopha macrolopha (koklass) and Gallus gallus (red jungle fowl) both emerge as non-pheasant genera. Monophyly of the pheasant group is challenged if Pucrasia macrolopha macrolopha and Gallus gallus are considered to be pheasants. The placement of Catreus wallichii (cheer) within the pheasants also remains undetermined, as does the cause for the great sequence divergence in Chrysolophus pictus obscurus (black-throated golden). These results suggest that alterations in taxonomic classifications may be required for some pheasant species and genera.  相似文献   

17.
Population genetic theory and empirical evidence indicate that deleterious alleles can be purged in small populations. However, this viewpoint remains controversial. It is unclear whether natural selection is powerful enough to purge deleterious mutations when wild populations continue to decline. Pheasants are terrestrial birds facing a long-term risk of extinction as a result of anthropogenic perturbations and exploitation. Nevertheless, there are scant genomics resources available for conservation management and planning. Here, we analyzed comparative population genomic data for the three extant isolated populations of Brown eared pheasant (Crossoptilon mantchuricum) in China. We showed that C. mantchuricum has low genome-wide diversity and a contracting effective population size because of persistent declines over the past 100,000 years. We compared genome-wide variation in C. mantchuricum with that of its closely related sister species, the Blue eared pheasant (C. auritum) for which the conservation concern is low. There were detrimental genetic consequences across all C. mantchuricum genomes including extended runs of homozygous sequences, slow rates of linkage disequilibrium decay, excessive loss-of-function mutations, and loss of adaptive genetic diversity at the major histocompatibility complex region. To the best of our knowledge, this study is the first to perform a comprehensive conservation genomic analysis on this threatened pheasant species. Moreover, we demonstrated that natural selection may not suffice to purge deleterious mutations in wild populations undergoing long-term decline. The findings of this study could facilitate conservation planning for threatened species and help recover their population size.  相似文献   

18.
暂时与群体分离的个体藏马鸡的反捕食警戒   总被引:3,自引:0,他引:3  
卢欣 《动物学报》2004,50(1):32-36
通过与同伴分担捕食风险 ,生活在稳定群体中的个体动物可以获得长期的适合度利益 ,但同时它们不得不承担食物竞争所带来的潜在代价。这种代价常常取决于食物资源的类型。当好的食物资源出现时 ,一些个体可以离开群体而独享这种资源。了解这些临时游离者如何组织其反捕食行为 ,在进化生态学上是有意义的。藏马鸡 (Crossoptilonharmani)是西藏雅鲁藏布江中游高山灌丛植被的一种典型的非繁殖季节集群鸟类。野外观察表明 ,为了独享好的食物资源 ,一些个体常常远离当前群体的活动范围。分离事件更可能发生于大的群体 ,但其发生率与参与者的数量呈负相关 ;而参与分离的个体愈多 ,分离持续的时间就愈长。分离者的个体警惕水平随着临时群体大小的增加而下降 ,遵从在其它自然大小鸟类群体所发现的一般性规律。分离行为的发生和持续时间被认为是个体对当前食物回报和捕食风险进行权衡的结果。这种利益 -代价权衡也可以解释藏马鸡所具有的强烈集群行为  相似文献   

19.
Summary Sand sheets near Darwin support a distinct heathland vegetation type which includes the habitat of several threatened species. Sand and gravel are extracted from shallow mines in this region. Woody vegetation recovery in 31 small, shallow former sand or gravel mine sites near Darwin that were up to 27 years old was assessed and compared to paired unmined control sites. Recovery in vegetation structure within each mine was calculated as the percentage of that in the control site. Mined sites recovered about 50% of their stem count and canopy cover, but only about 10% of basal area and mature tree count. Gravel mines showed poorer recovery than sand mines. Time since mining had no significant effect on the extent of recovery, but deeper mines had significantly poorer recovery. Only 35% of woody species in sand controls were present in mine sites, and 41% of gravel control species were present in former mine sites. It is unlikely that recovery will significantly improve in coming decades. Sand mining affects about 40 ha of land per year in this region, but is likely to increase in the future. If Darwin expands to a population of 1 million people, and mine sites are not fully rehabilitated, all of the sand‐sheet vegetation in the region could be removed in the next 100 years. Improved rehabilitation and protection is crucial for the conservation of heathland vegetation in this region.  相似文献   

20.
The Hainan peacock pheasant is an endangered taxon found only on Hainan Island of China. Due to lack of detailed taxonomic studies, whether it is a subspecies of the grey peacock pheasant (Polyplectron bicalcaratum katsumatae) or a full species (Polyplectron katsumatae) remained unclear. We used molecular markers, including the complete mitochondrial cytochrome b gene and intron G of the nuclear ovomucoid gene, to reevaluate the taxonomy of the Hainan peacock pheasant. The results showed phylogeographic monophyly and large genetic distance between the Hainan peacock pheasant and the grey peacock pheasant. Sequence differences corroborated the species-level distinction between these two peacock pheasants, which were inferred to have diverged about 1.4+/-0.3 million years ago, near the time Hainan Island became separated from mainland China. Because the population density of the Hainan peacock pheasant is very low in its tropical forest on the island and the wild population is declining, it is now becoming severely endangered and should be ranked as the rarest species in the Order Galliformes in China. Our results increase the urgency of getting more morphological data to support the classification of the Hainan peacock pheasant as a distinct species and taking more conservation action immediately to protect this endangered island species.  相似文献   

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