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1.
Summary Data on mammalian, avian and invertebrate biomass in mixed broadleaf-podocarp forest of the Orongorongo Valley are summarised and compared with the biomass in other forests. Animal biomass totalled at least 504 kg/ha — more than twice that in several tropical forests but less than that reported from temperate deciduous forests of Europe. Earthworms (333 kg/ha) provided most animal biomass: arthropods at least 145 kg/ha, mammals (all introduced) 25 kg/ha, and birds 0.6 kg/ha. By world standards the biomass of mammals, and litter-dwelling and underground arthropods, is high and that of birds moderate. Introduced mammals have greatly altered the distribution of biomass in this forest, herbivores and predatory mammals gaining biomass at the expense of some native aboveground invertebrates and birds, several of which have been lost to this community.  相似文献   
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A continuous-flow NMR culture system for mammalian cells has been developed on which 31P-NMR experiments under complete and strictly physiologic conditions have been performed. Observations on the response of the cellular metabolism to stresses such as starvation, low temperature and changes in environmental pH monitored by 31P-NMR are reported. The response of the intracellular pH relative to the external pH of the growth medium is studied. We find that under the experimental conditions used there exists a ΔpH varying between less than 0.2 and more than 0.6 pH units. These results are compatible with those obtained using other techniques.  相似文献   
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2017年5~11月,我们在四川亚丁国家级自然保护区内共布设64台红外相机,对保护区内的兽类和鸟类多样性进行了调查。经过8 394个相机工作日的调查,我们共鉴定出分属9目26科共56种的野生兽类和鸟类,其中国家Ⅰ级、Ⅱ级重点保护野生动物分别有5种和13种,被IUCN红色名录评估为濒危(EN)、易危(VU)、近危(NT)的野生动物分别有2种、3种和6种。相对多度指数居前三位的兽类和鸟类分别是毛冠鹿(Elaphodus cephalophus)、珀氏长吻松鼠(Dremomys pernyi)、猕猴(Macaca mulatta)和血雉(Ithaginis cruentus)、大噪鹛(Garrulax maximus)、雉鹑(Tetraophasis obscurus)。本次调查初步了解了亚丁保护区内鸟兽的种类、丰富度、分布以及人为干扰情况,是亚丁国家级自然保护区第一次开展鸟兽的本底资源调查和研究。我们的调查结果对掌握亚丁国家级自然保护区的鸟兽种类和分布现状等本底资料具有重要意义,同时也为保护区今后的科研工作及开展野生动物的保护管理和长期监测提供了数据支持和指导。  相似文献   
5.
为了解三江源国家公园野生兽类的分布现状,2015-2017年对园区进行了实地调查。根据调查结果并参考相关文献资料,三江源国家公园内野生兽类共62种,分别隶属8目19科44属。园区内兽类呈现出物种多样性高,珍稀濒危物种多,特有种多的特点:三江源国家公园内的兽类物种多样性G-F指数为0.77,表明该区域物种多样性处于很高水平。根据中国物种红色名录,20个物种受威胁(极危、濒危和易危),比例为32.26%,远高于国家整体水平;中国或青藏高原特有种29种,占46.77%。三江源国家公园在动物地理区划上属于古北界青藏区,在地理分布型上,以古北界成分为主,东洋界成分为辅,以古北界高山型成分最多,有25种,且资源量大,表明三江源国家公园的兽类以适应高寒气候的特殊种类为主。3个园区的平均动物区系相似性比较结果表明,长江源园区与澜沧江源园区为共同关系,黄河源园区与长江源园区和澜沧江源园区为密切关系。近些年,三江源地区的兽类保护工作取得了很好的效果,并得到国内外认可,本研究结合园区生物多样性和区系特点,根据保护现状,提出了今后的监测保护建议。  相似文献   
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Following a recent chronostratigraphic revision of 17 fossiliferous sites hosting assemblages constituting local faunas of the Aurelian Mammal Age for peninsular Italy, we provide a re-structured biochronological framework and discuss the current validity and significance of the middle Pleistocene Faunal Units (FU) for this region. Contrasting with the previous model of a wide faunal renewal during Marine Isotope Stage (MIS) 9 (∼ 330 ka), the First Occurrences (FO) of several species of the Torre in Pietra FU are significantly backdated and referred to the Fontana Ranuccio FU (530–400 ka). We show that the faunal renewal was more gradual and occurred earlier than previously assumed. Many taxa that are typical of the late Pleistocene register their FO in the Fontana Ranuccio FU, latest Galerian, which is characterized by the almost total disappearance of Villafranchian taxa and by the persistence of typical Galerian taxa such as Dama clactoniana, Bison schoetensacki and Ursus deningeri, and by the FO of Stephanorhinus kirchbergensis, S. hemitoechus, Hippopotamus amphibius, Cervus elaphus eostepahnoceros, Ursus spelaeus, Canis lupus, and Vulpes vulpes. The next Torre in Pietra FU is characterized only by the FO of Megaloceros giganteus and Mustela putorius. However, we observe that MIS 9 marks the actual moment when the faunal assemblages of this region are represented only by those taxa characterizing the late middle Pleistocene and late Pleistocene. For this reason, we propose to still consider the Torre in Pietra (lower levels) local fauna as a conventional boundary for the Galerian-Aurelian transition. Finally, we remark that the strong faunal renewal in MIS 13, with five FOs, coincides with the temperate climatic conditions due to the absence of marked glacial periods that could have favored the FO and the subsequent spread of these taxa.  相似文献   
7.
In order to explore the importance of indigenous agroforestry systems for biodiversity conservation, we compared the abundance, species richness and diversity of dung beetles and terrestrial mammals across a gradient of different land use types from agricultural monocultures (plantains) to agroforestry systems (cocoa and banana) and forests in the BriBri and Cabécar indigenous reserves in Talamanca, Costa Rica. A total of 132,460 dung beetles of 52 species and 913 tracks of 27 terrestrial mammal species were registered. Dung beetle species richness and diversity were greatest in the forests, intermediate in the agroforestry systems and lowest in the plantain monocultures, while dung beetle abundance was greatest in the plantain monocultures. The number of mammal tracks per plot was significantly higher in forests than in plantain monocultures, whereas mammal species richness was higher in forests than in either cocoa agroforestry systems or plantain monocultures. Species composition of both terrestrial mammals and dung beetles also varied across the different land use types. Our study indicates that indigenous cocoa and banana agroforestry systems maintain an intermediate level of biodiversity (which is less than that of the original forest but significantly greater than that of plantain monocultures) and provide suitable habitat for a number of forest-dependent species. Although the agroforestry systems appear to serve as favorable habitats for many terrestrial mammal species, their potential positive contribution to mammal conservation is being offset by heavy hunting pressure in the reserves. As in other agricultural landscapes, the conservation of biodiversity in Talamanca will depend not only on maintaining the existing forest patches and reducing the conversion of traditional agroforestry systems to monocultures, but also on reducing hunting pressure.  相似文献   
8.
We collated an environmental history for a 8580 km2 study area in the Simpson Desert, Australia. Quantitative and qualitative data on climate, land-use, fire history and ecosystem dynamics were used to construct a chronology of processes threatening terrestrial mammal species. Over the last 150 years there has been the transition in land tenure from a hunter–gatherer economy to pastoralism, the loss of 11 mammal species, the cessation of small scale burning by Aboriginal people and the introduction of the fox and cat. Annual rainfall was highly variable and was influenced by the phase of the El Niño Southern Oscillation (ENSO). Irruptions of rodents, marked increases in the populations of native and introduced predators and extensive wildfires were associated with the La Niña phase of ENSO and occurred when rain-year (July–June) rainfall approached or exceeded the 90th percentile of the historical rainfall distribution. Large rainfall events in arid Australia have been viewed traditionally as the ‘boom’ times that benefit wildlife and pastoral production. However, because of hyper-predation and the risk of wildfire, we show that the years including and immediately following flooding rains should be identified as critical, or ‘bust’ periods for wildlife and conservation management. ENSO related climatic forecasts appear to be useful cues which can be incorporated into fire and predator management strategies in arid Australia. Studies such as this, which utilise a broad range of data types across extensive areas, can identify the timing and potential of threatening process not possible using contemporary studies alone.  相似文献   
9.
基因组编辑技术可以对DNA或RNA进行精准改造,极大地促进了生命科学的发展。CRISPR/Cas9系统在靶位点诱导DNA发生双链或单链损伤,细胞对损伤部位采用无供体模板的非同源末端连接(non-homologous end joining,NHEJ)或有供体模板的同源重组(homologous recombination,HR)修复。基于HR的基因组编辑策略通常被用于获得DNA的精准改造,而NHEJ在动物DNA损伤修复中起主导作用。为了提升HR效率,研究人员设计了多种方案,包括CRISPR/Cas9系统优化和DNA修复通路调控等。从DNA损伤修复途径、Cas9变体选择、sgRNA设计、供体模板设计、DNA修复途径相关蛋白功能调控、供体模板募集效率提升、细胞周期调控及编辑细胞生存效率提升等方面详细综述了相关研究成果,发现尚未开发出放之四海而皆准的HR提升策略,基于HR的基因组编辑需要针对具体案例制定个体化策略。旨在为动物基因组编辑中提升CRISPR/Cas9介导的HR效率研究提供理论参考,为动物基因功能分析、基因治疗和经济动物基因编辑育种提供帮助。  相似文献   
10.
王德华 《兽类学报》2011,31(1):15-19
本文简要论述了我国哺乳动物生理生态学(主要是啮齿动物)的几个主要领域(方向)的研究进展,如
对环境的适应和瘦素的生理功能。根据国际发展动态,对未来一些可能的发展方向提出了建议。  相似文献   
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