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1.
Vanessa Hull Ashton Shortridge Bin Liu Scott Bearer Xiaoping Zhou Jinyan Huang Shiqiang Zhou Hemin Zhang Zhiyun Ouyang Jianguo Liu 《Plant Ecology》2011,212(1):43-54
Wildlife species are threatened by massive habitat destruction worldwide. Habitat fragmentation and isolation spatially constrain
animals and in turn cause non-sustainable rates of animal foraging on plant populations. However, little empirical research
has been done in large controlled settings to investigate foraging impacts. We conducted an experiment to characterize the
impact of panda foraging on the sustainability of its food resource, bamboo, in an enclosed area of natural habitat (approximately
19 ha). We monitored bamboo density, age, and percent cover throughout the enclosure across a 3-year period. We documented
marked declines in bamboo density and percent cover as a result of panda foraging, particularly in younger bamboo age classes.
We constructed simultaneous autoregressive models to explain bamboo loss to panda foraging and subsequent bamboo recovery
as a function of habitat conditions. Areas with high initial bamboo cover not only were prone to high rates of bamboo percent
cover loss but also experienced high rates of subsequent bamboo recovery, as bamboo cover loss opened up the understory for
new growth. Variograms of ordinary least squares model residuals revealed that the range of spatial autocorrelation in bamboo
loss increased over time as available bamboo forage declined. The results have implications for understanding the impact of
animal foraging on vegetation and also highlight the importance of preventing further habitat fragmentation and isolation. 相似文献
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采笋对大熊猫主食竹八月竹竹笋生长的影响 总被引:2,自引:0,他引:2
采笋是大熊猫栖息地内一种持续的人类干扰活动。为了评估采笋对大熊猫主食竹竹笋生长发育的影响,2009年7—11月,在四川省洪雅县瓦屋山镇设置实验样方,对比研究了早期采笋、中期采笋、晚期采笋、一直采笋和不采笋5种采笋方式对大熊猫主食竹八月竹竹笋生长和发育的影响。结果表明:1)早期采笋、中期采笋和一直采笋样方的发笋量显著高于不采笋样方(P0.05),其发笋量分别是不采笋的1.53倍,1.57倍和1.62倍;晚期采笋样方发笋量与不采笋样方差异不显著(P0.05)。2)早期采笋使八月竹在发笋早期和发笋中期的发笋量增加,中期采笋仅使八月竹在发笋中期的发笋量增加,而一直采笋使八月竹在整个发笋期的各个阶段的发笋量均显著增加(P0.05)。3)一直采笋样方的幼竹数量、株高均显著低于其他采笋样方,其基径只显著低于不采笋样方(P0.05);早期、中期、晚期采笋和不采笋样方相互间仅幼竹株高差异显著(P0.05)。4)早期、中期和晚期采笋与不采笋样方的发笋总量、退笋总量和采笋总量相互之间均呈显著正相关(P0.05)。建议仅在八月竹发笋中期采笋,同时政府应加大对大熊猫栖息地周边社区经济发展的引导和扶持。 相似文献
3.
By using PCR cloning techniques, the DNA sequences of the HMG box regions of sixSox genes (pSox) and the zinc finger domains of twoZfz genes (pZfx) in the giant panda were identified. The giant pandaSox genes fell into two subfamilies,SOX-S1 andSOX-S2. ThepSox andpZfx genes of the giant panda were highly homologous to the corresponding genes in mammals and revealed close substitution rates to those in the primates. 相似文献
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基于王朗国家级自然保护区1997—2009年的连续监测数据,利用分布频率法和Bai-ley法,从地形因子、森林群落结构和主食竹3个方面研究了大熊猫的生境选择特征.结果表明:王朗国家级自然保护区的大熊猫对生境具有明显的选择性.在地形上,多选择海拔在2500~3000 m的山体脊部、上部和中部的均匀坡和凸坡,坡向西南,坡度在6°~30°,与水源距离>300 m的环境;森林群落结构上,多选择起源为次生林、针阔混交林,微生境为竹林的生境,乔木平均高度在20~29 m,灌木盖度在0~24%;主食竹多选择平均高度在2~5 m,竹丛盖度>50%,混生,生长状况良好的缺苞箭竹. 相似文献
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圈养雄性大熊猫尿中睾酮激素水平的测定 总被引:1,自引:0,他引:1
本文对圈养的两只雄性大熊猫尿中睾酮激素进行了测定与比较,结果表明该老龄大熊猫“菲菲”与壮年大熊猫“川川”在同一时期内尿中睾酮激素含量基本处于相同水平,两者没有显著差异。由此可见老龄雄性大熊猫“菲菲”仍具有繁殖能力。 相似文献
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本文对圈养的两只雄性大熊猫尿中睾酮激素进行了测定与比较,结果表明该老龄大熊猫"菲菲"与壮年大熊猫"川川"在同一时期内尿中睾酮激素含量基本处于相同水平,两者没有显著差异.由此可见老龄雄性大熊猫"菲菲"仍具有繁殖能力. 相似文献
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Prakash P. Kumar Ian M. Turner A. Nagaraja Rao K. Arumuganathan 《Plant biotechnology reports》2011,5(4):317-322
We determined the nuclear DNA content (genome size) of over 35 accessions each of bamboo and rattan species from Southeast
Asia. The 2C DNA per nucleus was quantified by flow cytometry. The fluorescence of nuclei isolated from the leaves and stained
with propidium iodide was measured. The genome size of the bamboo species examined was between 2.5 and 5.9 pg DNA per 2C nucleus.
The genome size of the rattan species examined ranged from 1.8 to 10.5 pg DNA per 2C nucleus. This information will be useful
for scientists working in diverse areas of plant biology such as biotechnology, biodiversity, genome analysis, plant breeding,
physiology and molecular biology. Such data may be utilized to attempt to correlate the genome size with the ploidy status
of bamboo species in cases where ploidy status has been reported. 相似文献
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1999年 1 0月发现成都大熊猫研究基地的多只大熊猫体表面部、大腿外侧等处出现黄色、团状赘生物 ,致使患病熊猫出现搔痒、烦燥不安、食欲减退、脱毛等症状。刚出生一月多的雌性双胞胎熊猫幼仔也同时出现类似症状。工作人员刮取该赘生物浸泡于无水酒精中送检。经过显微镜观测 ,成虫镜下形态特征如下 :虫体呈卵圆形 ,似西瓜籽 ,体呈黄褐色。大小平均为32 9 0 0± 2 3 62× 2 2 4 33± 1 5 0 3μm ,♀ >♂ (照片 ,见封4 )。头部腭体短小 ,螯肢呈钳形。躯体不分节 ,有线纹 ,并具有硬化的板。体周有刚毛。雄性成虫腹面可见胸板和腹板 ,雌性成虫… 相似文献
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大熊猫和小熊猫粪便DNA提取的简易方法 总被引:29,自引:0,他引:29
采集了大熊猫和小熊猫的新鲜粪便样品 ,使用 1 0 0 %乙醇保存。通过重复离心富集研究动物的肠道脱落细胞 ,并使用乙醇和双蒸水洗涤以除去抑制物。用 1 %的SDS快速裂解细胞 ,离心除去残渣后 ,向裂解液中加入蛋白酶进行消化。消化结束后使用等体积的酚 /氯仿抽提 ,乙醇沉淀DNA。用双蒸水溶解粪便DNA后 ,使用PCR产物纯化试剂盒对粪便DNA进行纯化。电泳检测结果显示 ,从乙醇保存的大、小熊猫粪便样品中抽提到高质量的粪便DNA。对线粒体控制区、细胞色素b基因、 1 2SrRNA基因的PCR扩增反应以及测序结果也证实了样品保存方法和DNA抽提方法可靠而高效。此方法使用实验室内常用的分子生物学试剂 ,不仅克服了分子粪便学研究中常见的抑制物粪便DNA微量降解严重等障碍 ,与商业化的粪便抽提试剂盒 (QIAampDNAStoolMiniKit,Qiagen)相比还是一种经济的试验方法 (抽提反应成本为试剂盒的 1 / 5 )。文中还对粪便DNA内细菌基因组等背景DNA可能对分子粪便学试验结果的影响进行了探讨。在基于PCR技术的遗传学研究中 ,对于植食性动物而言 ,粪便内的背景DNA对目标动物DNA片断的扩增和序列测定未见影响 ;但对于肉食性动物 ,则必须考虑被捕食者基因组对试验可能产生的影响 ,应谨慎对待 相似文献
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Culture of skeletal muscle cells from giant panda 总被引:2,自引:0,他引:2
Liu JL Chen YC Sun QY Song XF Chen DY 《In vitro cellular & developmental biology. Animal》1999,35(10):553-554
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108国道秦岭生物走廊带大熊猫主要伴生动物调查 总被引:1,自引:0,他引:1
2009—2010年。作者利用红外感应照相机对108国道秦岭生物走廊带废弃公路两侧大熊猫主要伴生动物进行了调查,共布设红外相机45架次,计843个照相日,记录到大、中型兽类12种。该区域遇见次数相对较多的是小麂(Muntiacus reevesi),总计遇见38次;其次是野猪(Sus scrofa)32次,鬣羚(Naemorhedus sumatraensis)22次,平均遇见率分别为(24.50±1.93)%、(20.08±1.43)%和(13.95±1.91)%。金猫(Profelis temmincki)、青鼬(Mattes flavigula)、猪獾(Arctonyx coBaris)遇见次数相对较少,仅为5次、4次、2次,平均遇见率分别为(3.15±1.52)%、(2.44±0.97)%、(1.25±0.72)%,不同物种遇见次数频率差异极显著(x^2=112.472,df=11,P〈0.01).遇见率的差异一定程度上反映了该物种相对数量的多少,而海拔高度不同是影响走廊带内大熊猫伴生动物分布的主要因素。 相似文献
16.
Endophytic fungi associated with cacti in Arizona 总被引:2,自引:1,他引:2
Trichur S. Suryanarayanan Sally K. Wittlinger Stanley H. Faeth 《Mycological Research》2005,109(5):635-639
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O. V. Isaeva A. M. Glushakova S. A. Garbuz A. V. Kachalkin I. Yu. Chernov 《Biology Bulletin》2010,37(1):26-34
It was found that plant storage tissues (fleshy sugar-containing fruits, subsurface metamorphically altered plant organs (storage roots, tubers, etc.), and starch-containing seed lobes) nearly always contain yeasts that are able to actively reproduce in these tissues causing no visible damage. Within storage tissues, yeast cells were detected both in the intercellular space and inside plant cells. In the tissues of fleshy fruits, endophytic yeasts are represented by the same species as epiphytic ones; cryptococci of the order Filobasidiales and ascomycetes belonging to the genera Hanseniaspora and Metschnikowia are predominant. In subsurface plant organs, red pigmented basidiomycetous yeasts of the genus Rhodotorula prevail. Selective growth of representatives of one species, Candida railenensis, is typical of starch-containing storage tissues of seeds. The results obtained change the established notion of the distributional patterns of yeast fungi in natural habitats and suggest that internal storage tissues of plants can be considered as a new interesting model for studies of coevolving plant-microbial associations. 相似文献
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Identification and cross-species amplification of EST derived SSR markers in different bamboo species 总被引:1,自引:0,他引:1
Vikas Sharma Pankaj Bhardwaj Rahul Kumar Ram Kumar Sharma Anil Sood Paramvir Singh Ahuja 《Conservation Genetics》2009,10(3):721-724
The availability of expressed sequence data derived from gene discovery programs became an alternative source of mining simple
sequence repeat (SSR) and developing inexpensive genetic markers for the crop improvements. In present study, 10 express sequence
tags (EST)-SSR markers were identified from Bambusa oldhamii public sequence data base. Transferability to 25 species of Bambusoideae ranged from 30% to 100%. The number of alleles detected
per locus ranged from 2 to 10. All the newly identified SSR markers were found to be moderately to highly polymorphic with
an average Polymorphic Information Content (PIC) value of 0.54. As these loci represents transcribed region and recorded high
level of cross transferability and reliable amplification across the species, demonstrating the utility of these markers for
functional and genetic analyses of bamboo species. 相似文献
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Different species ofArthrobotrys nematophagous fungi and several strains ofA. oligospora have been studied for their antagonistic effects against nematodes of the genusMeloidogyne, important pests of vegetables. All fungi trappedM. mayaguensis andM. incognita juvenilesin vitro but had no effect on the juveniles ofM. javanica. In pot experiments withM. mayaguensis, all fungi reduced the nematode populations and stimulated the growth of tomato seedlings. In a field trial, a strain of A.oligospora, isolated in Senegal and incorporated into compost blocks, was efficient in increasing the tomato seedling growth. The introduction of nematophagous fungi in compost blocks as a biological biocontrol technique against phytophagous nematodes adapted for developing countries is discussed. 相似文献