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61.
该文描述了自云南东南部发现的荨麻科楼梯草属一新种,南溪楼梯草(Elatostema nanxiense)。此新种与田林楼梯草(E. tianlinense)相似,但其叶具三出脉,边缘具浅圆齿或小钝齿,雄总苞苞片较少,8枚,排成一层,背面有1~3条纵肋,只1枚在顶端具角状突起而与后者相区别。此外,此新种与盘托楼梯草系的广布种盘托楼梯草(E. dissectum)的区别在于其茎被糙伏毛,叶呈椭圆形,具三出脉,雄头状花序的花序梗较短,雄总苞苞片较少,呈宽卵形或横长方形,背面有1~3条纵肋,雄小苞片有缘毛。 相似文献
62.
63.
Cindy Q. Tang Yongchuan Yang Arata Momohara Huan-Chong Wang Hong Truong Luu Shuaifeng Li Kun Song Shenhua Qian Ben LePage Yi-Fei Dong Peng-Bin Han Masahiko Ohsawa Buu Thach Le Huu Dang Tran Minh Tri Dang Ming-Chun Peng Chong-Yun Wang 《Plant Diversity》2019,(4):237-249
The Chinese water pine Glyptostrobus pensilis is the sole surviving species of the genus Glyptostrobus. It is endemic to southern China, central Vietnam, and eastern Laos, and today it is nearly extinct in the wild. Forest community characteristics and population structure of G. pensilis in China have remained un-known up to now. We investigated six swamp forest stands and analyzed their forest community characteristics (i.e. vertical stratification, species composition, and diversity) and population structure, including the frequency distribution of DBH (diameter at breast height) and age-classes as found in Fujian Province, southeastern China. The vertical stratifications of all the forest stands were rather simple. The remaining wild specimens ranged from roughly 15 to some 357 years for an average of ca. 85 years, with only a few individuals less than 20 years old. Compared with the stands and populations of G. pensilis in Vietnam, the taxonomic compositions of the stands in the two regions were different, except for the dominant species-G. pensilis. The Shannon-Wiener index showed the overstory of each stand had much lower diversity (0.26 on average) in Fujian Province than that (1.97 on average) in Vietnam, whereas the diversity indices were about the same (around 2.41) for the understories in the two regions. Furthermore, we discovered 18 G. pensilis seedlings at the study sites in Fujian Province. This discovery demonstrates that G. pensilis regeneration is extremely poor and its populations are declining, although these populations are rela-tively healthier than those in Vietnam. 相似文献
64.
报道了贵州省凤仙花属(Impatiens)6个新记录种(含1变种),分别是锐齿凤仙花(Impatiens arguta Hook.f.& Thomson.)、线萼凤仙花(Impatiens linearisepala S.Akiyama, H.Ohba & S.K.Wu)、川鄂凤仙花(Impatiens fargesii Hook.f.)、林生凤仙花(Impatiens lucorum Hook.f.)、雅致黄金凤(Impatiens siculifer var. mitis Lingelsheim & Borza)和田林凤仙花(Impatiens tianlinensis S.X.Yu & L.J.Zhang)。该文提供了新记录种形态特征照片和地理分布,凭证标本保存于贵州大学林学院树木标本室(GZAC)。 相似文献
65.
Toward a better understanding of the "Transverse Range break": lineage diversification in southern California 总被引:1,自引:0,他引:1
Chatzimanolis S Caterino MS 《Evolution; international journal of organic evolution》2007,61(9):2127-2141
The Transverse Ranges in southern California have been identified as having a prominent phylogeographic role. Numerous studies have identified distinct north-south and/or east-west lineage breaks involving the Transverse Ranges. However, in evaluating their findings, most authors have regarded this complex system somewhat simplistically. In this study we more deeply investigate these breaks using two approaches: first we examine the phylogeographic history of Sepedophilus castaneus (Coleoptera: Staphylinidae) and then implement a comparative phylogeography approach applying Brooks parsimony analysis to the topologies of nine additional taxa. Phylogenetic analysis, nested clade analysis, and AMOVAs for S. castaneus agree that there is a major lineage break between the eastern and western Transverse Ranges, localized between the Sierra Pelona and the San Gabriel Mountains. The comparative phylogeographic analysis supports a generally strong concordance of area relationships with geographic proximity. It is notable, however, that the Transverse Ranges as a group do not show phylogenetic cohesion, but rather they are split into three main regions: an eastern region (San Gabriel, San Bernardino, and San Jacinto Mountains), a central region (central Transverse Ranges and Sierra Pelona) that is often grouped with the Tehachapi and Sierra Nevada populations, and a western region (northwestern Transverse Ranges and Santa Ynez Mountains) that is consistently grouped with coast range areas to the north. The lineage break between east and west Transverse Ranges is attributable to the presence of a marine embayment in what is now the Santa Clara River valley 5-2.5 million years ago. 相似文献
66.
Correlation between the animal community structure and environmental factors in Jialiang and Boduo caves of Guizhou Province, China
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Li Daohong 《农业工程》2007,27(6):2167-2176
1045 samples collected in Boduo cave belong to 3 phyla, 6 classes, 13 orders, 27 families and 45 species or groups. 469 samples collected in Jialiang cave were subordinated to 3 phyla, 6 classes, 9 orders, 24 families and 52 species or groups. According to the analysis of the community diversity, the communities that have the highest values of richness, diversity, maximum diversity, evenness, dominance and community similarity are D (8.3223), D (3.4677), D (3.8286), D (0.9057), C (0.0404) and D-E (0.6611), respectively. According to the analysis of Pearson correlation, the content of organic matter in soil is strongly positively related to species number, species richness, community diversity and maximum community diversity, and is significantly positively related to the evenness. The content of CO2 in air is opposite to the above result and is negatively related to species number, species richness, community diversity, maximum community diversity and evenness. The results indicate that the contents of organic matter and CO2 are the important factors influencing the community structure of cave animals. 相似文献
67.
Studies in the past decade have proven the Shanita fauna to be an excellent marker of the northern peri-Gondwana tectonic blocks.Thus,a study of the Shanita fauna from the Baoshan area in western Yunnan Province,China,could provide pivotal paleontological evidence for the paleogeographic reconstruction of the Baoshan block.We systematically analyzed the composition and the age of the Shanita fauna from the Permian Da'aozi Formation in Woniusi Section of the Baoshan area.Results suggested that the characteristic genera Shanita and Hemigordiopsis in this fauna comprised eight species (including two new species),and ten genera of other nonfusulinid foraminifera were also recognized from this fauna.Further comparative study showed that the Shanita fauna from the Baoshan area were probably late Maokouan (Lengwuan)to Wuchiapingian in age.In general composition,this fauna is comparable to those Shanita faunas from Shan State of Burma,Peninsular Thailand,and Nagri of Tibet,China.However,the relatively low generic diversity and occurrence of some endemic species,as well as the absence of fusulinids,indicate certain regional features of the Shanita fauna from the Baoshan area. 相似文献
68.
该研究在建立贵州省野生苦苣苔科植物名录和地理分布数据库的基础上,对其物种多样性及地理分布格局进行研究。通过文献资料结合实地调查,从物种组成、特有性、水平分布、垂直分布和相似性等方面进行分析,并采用筛除算法确定贵州苦苣苔科植物分布的热点地区。结果表明:(1)贵州省苦苣苔科植物共计2族8亚族28属153种(含种下等级),分布在75个县级行政区,有128/45个中国/贵州特有种,垂直分布以900~1300 m海拔段最为丰富。(2)通过计算省级相似性系数,发现贵州与广西的相似程度最高,最后筛选得到10个热点县,共代表了75%的苦苣苔科植物。(3)贵州省为典型的喀斯特高原山地,苦苣苔科植物种类丰富,尤其是广义马铃苣苔属、广义报春苣苔属、广义石山苣苔属和蛛毛苣苔属等,有着较高的物种多样性和区域特有性。该研究可以为贵州省苦苣苔科植物资源保护和持续利用提供理论参考。 相似文献
69.
江苏省中国科学院植物研究所标本馆(NAS)是中国最早的植物标本馆之一,也是国内最早开展植物标本数字化的标本馆,其标本数字化发展经历了4个阶段: 20世纪80年代后期尝试的标本文字信息数字化的起步阶段; 20世纪90年代末的标本图像数字化和文字信息数字化规范阶段; 2004年以后的标本批量数字化与信息网络共享快速发展阶段; 2018年后的标本数字化信息维护与优化阶段。这一过程集中代表和反映了中国植物标本数字化的发展历程。此外,近年来开始了发掘和利用江苏植物标本的数字化信息工作,包括建设江苏省级数字植物标本馆、开发江苏省维管植物标本时空分布可视化系统、开展标本采集-入库过程数字化等。今后,将不断深化标本数字化的工作,以期形成有NAS特色的数字化植物标本馆。 相似文献
70.
Ting Zhang Jing Li Yong-Zhong Jiang Jun-Qiang Xu Xu-Hua Guan Li-Qiang Wang Jie Chen Yi Liang 《中国病毒学》2022,37(4):503-512
Group A human rotaviruses (RVAs) annually cause the deaths of 215,000 infants and young children. To understand the epidemiological characteristics and genetic evolution of RVAs, we performed sentinel surveillance on RVA prevalence in a rotavirus-surveillance network in Hubei, China. From 2013 to 2016, a total of 2007 fecal samples from hospital outpatients with acute gastroenteritis were collected from four cities of Hubei Province. Of the 2007 samples, 153 (7.62%) were identified positive for RVA by real-time RT-PCR. RVA infection in Hubei mainly occurred in autumn and winter. The highest detection rate of RVA infection was in 1–2 years old of outpatients (16.97%). No significant difference of RVA positive rate was observed between females and males. We performed a phylogenetic analysis of the G/P genotypes based on the partial VP7/VP4 gene sequences of RVAs. G9P[8] was the most predominant strain in all four years but the prevalence of G2P[4] genotype increased rapidly since 2014. We reconstructed the evolutionary time scale of RVAs in Hubei, and found that the evolutionary rates of the G9, G2, P[8], and P[4] genotypes of RVA were 1.069×10-3, 1.029×10-3, 1.283×10-3 and 1.172×10-3 nucleotide substitutions/site/year, respectively. Importantly, using a molecular clock model, we showed that most G9, G2, P[8], and P[4] genotype strains dated from the recent ancestor in 2005, 2005, 1993, and 2013, respectively. The finding of the distribution of RVAs in infants and young children in Hubei Province will contribute to the understanding of the epidemiological characteristics and genetic evolution of RVAs in China. 相似文献