612 resultados para Chinese Vegetation


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气候在大尺度上决定着植被的分布、结构和组成,植被结构和生理状态的改变可以通过改变植被的反射率、粗糙度以及水分通量进而影响气候,这样形成了气候一植被的相互作用。在植被一气候相互作用的研究中,植物功能型是重要的概念和方法,它可以在详尽描述植被生物物理和生理特征的同时,有效削减植被的复杂性。植物功能型的概念和方法已经在植物群落、生态系统的复杂性和功能、古植被和古气候研究,以及陆面过程模型和动态全球植被模型中得到了广泛的应用。但是针对我国植被-气候的相互作用和区域尺度的全球变化研究,还需要一套特定的植物功能型.生物群区体系。   本论文根据我国植被生态学和植被分类的研究背景,结合植被.气候相互作用和区域全球变化研究的需要,提出了一套适宜于中国的植物功能型.生物群区划分方案。首先,根据中国植被和气候特征,筛选并确定了影响植被生物物理和生理属性以及植被分布的6个关键的植物功能特征:然后,根据这6个特征,对植物进行功能型划分,得到了29类植物功能型:再根据我国植被的实际情况和研究需要,选定了其中的18类作为我国的植物功能型。这套功能型包括了7类‘树’功能型,6类‘灌木’功能型和5类‘草’功能型,其中含有4类高寒植物功能型,专门用于描述青藏高原的植被分布,并根据需要设置了2类‘裸地,功能型。   根据我国气候一植被分布定量关系的相关研究以及BIOME1和Box体系的研究结果,选定7个环境变量作为限制我国植物功能型分布的关键气候因子:最冷月平均气温、最暖月平均气温、大于50C的有效生长积温、大于OºC的有效生长积温、Priestley-Taylor系数(实际蒸散与潜在蒸散的比值)、降水量、最暖月和最冷月平均气温之差。采用半峰宽法初步确定每个植物功能型的环境限定因子取值范围。并根据这套植物功能型及其环境参数建立了适宜于我国的生物群区体系,从而得到了我国的植物功能型-生物群区体系(the Chinese Plant functional Types and Biomes,CNPB)。 为了验证这套植物功能型-生物群区体系,将BIOME1和中国的植物功能型生物群区体系(CNPB)对中国植被在当前气候条件和未来气候情景下分布的模拟结果进行了比较。结果表明,这套体系可以更有效地模拟中国植被在当前和未来气候条件下的分布,特别是对青藏高原植被描述的详细程度有实质性的提高。

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Chromosomal homologies have been established between the Chinese muntjac (Muntiacus reevesi, MRE, 2n = 46) and five ovine species: wild goat (Capra aegagrus, CAE, 2n = 60), argall (Ovis ammon, OAM, 2n = 56), snow sheep (Ovis nivicola, ONI, 2n = 52), red goral (Naemorhedus cranbrooki, NCR, 2n = 56) and Sumatra serow (Capricornis sumatraensis, CSU, 2n = 48) by chromosome painting with a set of chromosome-specific probes of the Chinese muntjac. In total, twenty-two Chinese muntjac autosomal painting probes detected thirty-five homologous segments in the genome of each species. The chromosome X probe hybridized to the whole X chromosomes of all ovine species while the chromosome Y probe gave no signal. Our results demonstrate that almost all homologous segments defined by comparative painting show a high degree of conservation in G-banding patterns and that each speciation event is accompanied by specific chromosomal rearrangements. The combined analysis of our results and previous cytogenetic and molecular systematic results enables us to map the chromosomal rearrangements onto a phylogenetic tree, thus providing new insights into the karyotypic evolution of these species.

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A set of Chinese muntjac (Muntiacus reevesi) chromosome-specific paints has been hybridized onto the metaphases of sika deer (Cervus nippon, CNI, 2n = 66), red deer (Cervus elaphus, CEL, 2n = 62) and tufted deer (Elaphodus cephalophus, ECE, 2n = 47). Thir

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We examined protein polymorphism of Chinese pangolins (Manis pentadactyla) from Yunnan Province of China, including two forms of three brown and nine dusky Chinese pangolins. Sixty-two genetic loci were screened; 12 loci were found to be polymorphic. The percentage of polymorphic loci (P) is 0.194, the mean individual heterozygosity (H) is 0.078, and the mean number of alleles (A) is 1.258. Furthermore, we calculated the genetic distance (D) between the two forms and found a low level of genetic divergence (D = 0.0206) between them, which indicates an almost-indistinguishable divergence at the level of proteins.