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1.
花尾榛鸡冬季活动区及社群行为   总被引:10,自引:0,他引:10  
孙悦华  方昀 《动物学报》1997,43(1):34-41
无线电遥测结果表明,长白山冬季花尾榛鸡的月活动区大小为22.5~6.52hm~2。11月至1月,随着天气变冷,花尾榛鸡的活动区面积明显减小(P<0.001)。冬季花尾榛鸡的日活动范围很小,平均466±127m~2。整个冬季花尾榛鸡的活动中心区出现阶段性改变。花角榛鸡对其活动区有一定的依赖性。花尾榛鸡冬季不存在明显的领域,出现集群行为,这与其栖息地食物丰富与抵御天敌有关。花尾榛鸡集群的组织结构是松散的,缺乏义务性,集群中的个体关系有亲疏,存在2只或2只以上个体组成的小组,同组个体之间的距离大多数情况在150~200m以内的联系范围内。推测花尾榛鸡集群时的活动区面积增大。  相似文献   
2.
20 0 2年 6~ 7月 ,在甘肃省莲花山自然保护区对云南柳莺的孵卵行为进行了研究。结果表明 ,雌鸟孵卵的日活动期为 (80 0 5± 42 8)min (n =1 5 ) ,每天离巢 (3 2 7± 3 9)次 (n =1 5 ) ,每次离巢时间 (6 6±1 8)min (n =5 99) ,每次坐巢时间 (1 8 4± 9 2 )min (n =5 83 ) ,坐巢率为 (73 1± 1 9) %。雌鸟每次坐巢时间和离巢时间的长度均与气温显著相关。日活动期雌鸟在巢的平均卵温为 3 2 3℃ ,夜晚的平均卵温为3 2 7℃。整个孵卵期卵温在发育临界值 2 8℃以上的时间比例为 92 7%。在孵卵后期卵温有逐渐上升的趋势。  相似文献   
3.
Zusammenfassung Zwischen 2. und 10. Mai 1997, dem Höhepunkt territorialer Aktivität, wurden im Lianhuashan-Reservat (Gansu, China) Territorial- und Werbeverhalten anhand von 18 farbberingten und besenderten Chinahaselhühnern mittels Ton- und Videotechnik verfolgt. Die Hähne markieren ihre Reviere durch instrumentale Flügelgeräusche, die durch Flattersprünge am Boden, seltener durch Revierflüge hervorgebracht werden. Die Flattersprunghäufigkeit kulminiert am frühen Morgen, die Nahrungsaufnahme am Abend. Die erste Paarung fand am 9. Mai statt.
Territorial and courtship behaviour of Chinese Grouse(Bonasa sewerzowi)
Summary Field observations, sound and video recordings of the rare endemic Chinese Grouse were carried out during May 2 and 10, 1997, the optimal time to study display, in the Lianhuashan reserve (Gansu province) at altitudes between 2800 and 3200 m a.s.l. We found the density in spring extraordinarily high: 15 occupied territories/km2 in the best studied plot. 18 colour-banded and radio-tagged birds were recorded. We were able to record on tape most of the vocal and instrumental sounds produced by the displaying grouse. Chinese grouse males perform a wing-beat display. The main elements of the territorial activity were variable flutter-jumps on the ground up to 1 m high and 2–4 m wide, sometimes also from a tree to the ground and vice-versa, producing instrumental sounds. An evident peak of flutter jumping activity was observed just after the birds left the roost tree in the morning (5.30 h local time) up to 8 o'clock. Noisy territorial flights in the crowns of trees were rarely observed. The low frequency sounds produced by the wings of the jumping cocks produced a typical impressive morning concert, especially, if 3–4 conflicting males came close together. First copulation was recorded on May 9. In the mating time, flutter jumping activity abated considerably.
  相似文献   
4.
 本文简要综述了80年代以来国际上对根黄酮在调节植物根生长、完善根功能、影响氮素循环及在施加他感作用方面的研究进展,并对有关方面作了一些展望,以期引起植物营养工作者对植物次生物质的注意。  相似文献   
5.
Cycas multipinnata C.J. Chen & S.Y. Yang is a cycad endemic to the Red River drainage region that occurs under evergreen forest on steep limestone slopes in Southwest China and northern Vietnam. It is listed as endangered due to habitat loss and over-collecting for the ornamental plant trade, and only several populations remain. In this study, we assess the genetic variation, population structure, and phylogeography of C. multipinnata populations to help develop strategies for the conservation of the species. 60 individuals from six populations were used for chloroplast DNA (cpDNA) sequencing and 100 individuals from five populations were genotyped using 17 nuclear microsatellites. High genetic differentiation among populations was detected, suggesting that pollen or seed dispersal was restricted within populations. Two main genetic clusters were observed in both the cpDNA and microsatellite loci, corresponding to Yunnan China and northern Vietnam. These clusters indicated low levels of gene flow between the regions since their divergence in the late Pleistocene, which was inferred from both Bayesian and coalescent analysis. In addition, the result of a Bayesian skyline plot based on cpDNA portrayed a long history of constant population size followed by a decline in the last 50,000 years of C. multipinnata that was perhaps affected by the Quaternary glaciations, a finding that was also supported by the Garza-Williamson index calculated from the microsatellite data. The genetic consequences produced by climatic oscillations and anthropogenic disturbances are considered key pressures on C. multipinnata. To establish a conservation management plan, each population of C. multipinnata should be recognized as a Management Unit (MU). In situ and ex situ actions, such as controlling overexploitation and creating a germplasm bank with high genetic diversity, should be urgently implemented to preserve this species.  相似文献   
6.
中国特有植物同钟花(桔梗科)的细胞学研究   总被引:1,自引:0,他引:1  
对分布我国西南的特有属同钟花属的同钟花(Homocodon brevipes)进行细胞学研究,其染色体数目为68,核型为2n=68=56m 10sm 2st,可能是四倍体。通过比较桔梗科已有的大量细胞学资料认为该类群应该与风铃草属和沙参属所代表的类群关系较近。  相似文献   
7.
利用扫描电镜首次观察了山茶科极濒危植物猪血木(Euryodendron excelsum)的花器官发生过程。猪血木的花为两性完全花,萼片和花瓣均为2/5螺旋向心发生,单轮排列,且有逆时针和顺时针两种方式。雄蕊的形成是先形成一个环形分生组织,然后在环形分生组织上以2/5螺旋产生5束雄蕊原基,每一束雄蕊原基的第一雄蕊原基都是在对萼的位置产生,其它的雄蕊原基在其两侧产生。3心皮顺序发生,愈合成3室单子房,柱头平截不裂。猪血木与山茶亚科的花器官发生明显不同。  相似文献   
8.
Giemsa-C带揭示的绵枣儿多倍体复合体染色体变异   总被引:3,自引:0,他引:3  
绵枣儿是分布在东亚的多倍体复合体。以Giemsa-C带法对分布在中国的绵枣儿24个居群进行了染色体变异分析。AA和BB细胞型大部分居群未发现变异,分别具a2和b1染色体的近着丝点着丝粒带。AABB虽无居群内变异,但居群间有所不同。其中柳林、商南和徐州居群带型相同,带纹丰富。元宝山居群只有b1的近着丝粒带,而灵岩山居群具a2和b1的近着丝粒带。根据已有的研究资料推测,绵枣儿b1和a2上的近着丝粒带显示的应当是高度重复的rRNA基因;大庆和文县居群一个体该位点的杂合可能是由于部分rRNA拷贝的同源染色体间转移;AABB起源后随时间推移会发生rRNA重复位点的丢失;柳林等居群丰富的带纹可能是其刚刚起源时重复基因关闭的表征,随时间推移同样可能会丢失。另外大量的实验证据表明,BB比AA细胞型可能更易于发生染色体结构变异。  相似文献   
9.
Intervention in B7 (CD80/CD86)/B7-ligand (CD28/CTLA-4) pathways is an effective way of preventing unwanted immune responses, such as allograft rejection. Pregnancy maintenance represents maternal tolerance to the fetal allograft, which is accompanied by a type 2 helper cell (Th2) bias at the maternal-fetal interface. Here, the costimulatory signal of CD86 was selectively blocked, and that of CD80 was kept unimpaired by administration of anti-murine CD86 monoclonal antibody at the early gestational stage in abortion-prone CBA/JxDBA/2 matings and normal pregnant CBA/JxBALB/c matings. It was demonstrated that in vivo blockade of CD86 costimulation could suppress maternal immune attack to the fetus by shifting cytokines from Th1 predominance to Th2 bias at the maternal-fetal interface, and expanding peripheral CD4+CD25+ regulatory T cells, which play an important role in the development and maintenance of maternal-fetal tolerance. Furthermore, the expression of CD28 and its ligands CD80/CD86 on peripheral lymphocytes was down-regulated, whereas that of CTLA-4 was up-regulated, which might facilitate the suppressive effect of CD4+CD25+ regulatory T cells on the alloreactive T cells. The maternal-fetal immunotolerance induced by CD86 blockade decreased fetal resorption in CBA/JxDBA/2 matings, but did not affect normal pregnant CBA/JxBALB/c matings. These results suggest that selective blockade of CD86 costimulation leads to maternal immune tolerance to embryo antigen, and might contribute to a rational immunoregulatory regimen for recurrent spontaneous abortion.  相似文献   
10.
记述采自中国云南省新小叶蝉属1新种,版纳新小叶蝉Singapora bannaensis sp. nov.及1中国新纪录种,阿氏新小叶蝉Singapora arifi Ghauri,1985。新种区别于属内其它种的特征在于:阳茎端部的刺突很长,其末端已超过阳茎干基部水平;阳茎前腔突基部膨胀,近中部骤细;腹内突长,伸达第7腹节。词源:新种种名取自采集地地名版纳。同时给出该属世界种类检索表,模式标本保存在贵州大学昆虫研究所。  相似文献   
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