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131.
Jun Chen Bo Wang Yan Zheng Hui Jiang Tian Jiang Hakan Bozdoğan Junqiang Zhang Baizheng An Xiaoli Wang Haichun Zhang 《Journal of Zoological Systematics and Evolutionary Research》2020,58(1):174-193
The Mesozoic family Procercopidae is widely treated as the ancient group of Cercopoidea and a transitional unit to recent lineages, but its evolution and diversity are vague due to fragmentary fossil record and confusing taxonomic history. Herein, an extensive taxonomic review of Procercopidae is presented and some new fossils are reported from the Lower Cretaceous Yixian Formation of NE China. As a result, Chengdecercopis Hong, 1983 is transferred from Procercopidae to Sinoalidae; Procercopis longipennis Becker-Migdisova, 1962 and P shawanensis Zhang, Wang and Zhang, 2003 are transferred to Procercopina Martynov, 1937, resulting in Procercopina longipennis (Becker-Migdisova, 1962), comb. n. and P shawanensis (Zhang, Wang and Zhang, 2003), comb. n.; Luanpingia senjituensis Hong, 1984 is transferred to Stellularis Chen, Yao and Ren, 2015, leading to Stellulari senjituensis (Hong, 1984), comb. n.; Anthoscytina macula Hu, Yao and Ren, 2014 is transferred to Sinocercopis Hong, 1982, and Sunoscytinopteris (Scytinopteridae) and Cathaycixius (Cixiidae) are treated as junior homonym names of Sinocercopis, leading to Sinocercopis macula (Hu, Yao and Ren, 2014), comb. n., S lushangfenensis (Hong, 1984), comb. n., S pustulosis (Ren, 1995), comb. n., and S trinervis (Ren, 1995), comb. n. Additionally, two new species are erected: Stellularis bineuris Chen and Wang, sp. n. and S minutus Chen and Wang, sp. n. Our cladistic analysis based on wing (tegmen and hind wing) characteristics recovers the high-level relationships within Cercopoidea: Sinoalidae + (Procercopidae + (Cercopionidae + modern cercopoids)). Within the family Procercopidae, the cladistic analysis reveals that the Middle to Late Jurassic Titanocercopis and Jurocercopis and the Cretaceous Cretocercopis occupy the basal position, and a gradual change in wing venation can be recognized from the Early Jurassic Procercopis and Procercopina to the Jurassic Anthoscytina, and then to the Cretaceous Stellularis and Sinocercopis. The two Cretaceous genera, sharing wing traits with extant cercopoids, likely represent transitional forms between Procercopidae and recent Cercopoidea; however, they are very similar to their Jurassic relatives in body structures, suggesting it is applicable to attribute them to Procercopidae. Furthermore, our analysis suggests that the extinction of Procercopidae and the origin and early diversification of modern Cercopoidea approximately coincided with the rise and explosive radiation of angiosperms in the late Early Cretaceous and onwards. 相似文献
132.
133.
2004-2016年贵州省石漠化状况及动态演变特征 总被引:3,自引:0,他引:3
石漠化是制约我国西南地区社会、经济、生态发展的重要因素之一,及时监测评估其演变状况,对区域石漠化防治及生态环境建设具有重要科学意义。选取2004-2016年间4期TM影像,研究贵州省域尺度上、石漠化时空演变特征和未来发展趋势。结果显示:1)2004-2016年间,贵州省78.3%的区域植被覆盖度上升,平均增加了19.1%,达到63.4%,有55.4%的区域岩石裸露率下降;2)贵州省石漠化空间分布呈现从东北到西南渐次加重的特征,西部毕节市中、重度石漠化面积占该区域面积仍达62.0%-86.4%,而东部黔东南州约为18.4%-33.0%;3)2004-2016年间,贵州省石漠化状况呈现总体持续好转态势,以轻、中度石漠化转入为主体的无石漠化面积增加了1.1倍,轻度石漠化增加了20.0%左右,中度和重度石漠化面积分别减少了40.0%左右;4)截止到2016年,贵州省无石漠化、轻、中、重度石漠化区域分别占比约42.0%、24.1%、23.5%、10.4%;5)未来2020年及2024年,贵州省石漠化仍将持续改善,石漠化面积占比将分别减少8.9%和12.2%。过去十多年间,贵州省石漠化状况得到基本遏制,但局部区域仍存在高度的不稳定性,或趋于恶化的风险,未来在各类政策措施的支持下,贵州省石漠化状况仍将继续好转,但部分重度石漠化区域的治理将更为复杂而艰难。 相似文献
134.
Chronological age conveys only a rough approximation of the maturational status of a person whereas skeletal maturity indicators give a more accurate estimation. Therefore, it is of interest to document the correlation between chronological and skeletal age using CVMI and modified MP3 methods. A total of 39 subjects between the age ranges of 9-16 years were selected for this study. Pre-treatment lateral cephalograms and hand-wrist radiographs of the subjects were used. The skeletal age was analyzed by the Cervical Vertebrae Maturity Index (CVMI) and modified MP3 methods. The data was analyzed with SPSS software version 23.00. Kendall''s Tau correlation test was performed to estimate the correlation between chronological age and skeletal age among the subjects and a linear regression test was also performed. Positive correlation was found between chronological age and skeletal age assessed by CVMI method (r= 0.398) and modified MP3 method (r=0.382) with p value >0.003. Thus it can be concluded that there was a positive correlation between chronological age and skeletal age among all the subjects. 相似文献
135.
该研究以采自新疆的100余份饼干衣属(Rinodina)地衣标本为研究材料,通过形态解剖特征观察、地衣化学成分分析以及分子生物学鉴定方法鉴定出9个种,包括2个中国新记录种——阿富汗饼干衣(Rinodina afghanica)和古氏饼干衣(Rinodina guzzinii),7个常见种分别是:包氏饼干衣(R. bohlinii)、毕氏饼干衣(R. bischoffii)、代谢饼干衣(R. metaboliza)、密果饼干衣(R. pycnocarpa)、特雷氏饼干衣(R. trevisanii)、甘肃饼干衣(R. straussii)和地生饼干衣(R. terrestris)。并提供了新疆饼干衣属地衣的分种检索表、每个物种的详细描述、新记录种的特征图片以及系统发育分析。 相似文献
136.
目的探讨生长抑素联合精准营养疗法对胃癌根治术患者术后营养指标水平和肠道菌群的影响。方法选取我院2017年10月至2019年1月收治并拟行胃癌根治术治疗的92例胃癌患者为研究对象,随机分为对照组(46例)和观察组(46例)。两组患者术后均给予常规处理。对照组患者同时给予生长抑素+常规肠外营养支持,观察组患者同时给予生长抑素+精准营养支持。于营养干预前后统计两组患者营养相关指标[体质量、血清白蛋白(ALB)、前白蛋白(PA)、淋巴细胞计数(LC)、肌酐(Ct)以及尿素氮(UN)]水平;对肠道菌群进行alpha分析,并计算肠杆菌、肠球菌、乳杆菌和双歧杆菌数量。结果营养干预前,两组患者营养相关指标水平以及肠道菌群相关指标水平之间差异无统计学意义(均P>0.05)。营养干预后,(1)观察组患者平均体质量以及血清ALB、PA、LC水平分别为(56.98±5.34)kg、(29.98±6.03)mg/L、(137.14±35.17)g/L、(1.15±0.26)×109,对照组分别为(53.29±5.18)kg、(26.12±5.29)mg/L、(104.53±27.66)g/L、(0.82±0.18)×109,两组之间差异有统计学意义(均P<0.05);(2)观察组患者肠道菌群Chao指数和Ace指数水平分别为(397.84±75.23)、(408.26±78.34),对照组分别为(362.13±66.23)、(371.19±70.09),两组之间差异有统计学意义(均P<0.05);(3)观察组患者肠道肠杆菌、肠球菌数量明显低于对照组,而乳杆菌、双歧杆菌数量明显高于对照组(均P<0.05)。结论胃癌根治术患者术后联合生长抑素和精准营养疗法能够显著改善患者的营养状况,保持肠道菌群丰度,平衡肠道菌群分布,值得临床研究和应用。 相似文献
137.
Csilla Stenger‐Kovcs Edina Lengyel Krisztina Buczk Judit Padisk Jnos Korponai 《Ecology and evolution》2020,10(1):320-335
Saline lakes, among the most seriously endangered ecosystems, are threatened due to climate change and human activities. One valuable feature of these environments is that they constitute areas of high biodiversity. Ecologists are, therefore, under great pressure to improve their understanding of the effects of natural and anthropogenic disturbances on the biodiversity of saline lakes. In this study, a total of 257 samples from 32 soda pans in Central Europe between 2006 and 2015 were examined. The effects of environmental variables and of geographical and limnoecological factors on functional diversity were analyzed. Furthermore, the explanatory power of the trait‐based approach was assessed, and the applicability of the indices for biomonitoring purposes was determined. It was found that low habitat heterogeneity and harsh environments lead to the selection of a small number of suitable traits, and consequently, to a naturally low level of functional diversity. Anthropogenic activities enhance diversity at functional level due to the shift toward freshwater characteristics. On the regional scale, the effects of the region and status (natural, degraded, reconstructed) on diatom functional diversity were significant and more pronounced than that of the environmental and other limnoecological factors. The degree of variance found in functional diversity ascribed to environmental variables is five times greater in the case of the application of a trait‐based approach, than when a taxonomic one is employed in the literature. Each of the tested functional diversity indices was sensitive to the most important environmental variables. Furthermore, these were type‐specific and proved to be more complex indicators than taxonomic metrics. It is possible to suggest four functional diversity indices (FGR, FRic, FDis, and FDiv) which emphasize their independence from substrate and seasonal variations for ecological status assessment and conservation planning. 相似文献
138.
Hannah L. Owens Vivian Ribeiro Erin E. Saupe Marlon E. Cobos Peter A. Hosner Jacob C. Cooper Abdallah M. Samy Vijay Barve Narayani Barve Carlos J. Muoz‐R. A. Townsend Peterson 《Ecology and evolution》2020,10(14):6967-6977
Reconstructing ecological niche evolution can provide insight into the biogeography and diversification of evolving lineages. However, comparative phylogenetic methods may infer the history of ecological niche evolution inaccurately because (a) species' niches are often poorly characterized; and (b) phylogenetic comparative methods rely on niche summary statistics rather than full estimates of species' environmental tolerances. Here, we propose a new framework for coding ecological niches and reconstructing their evolution that explicitly acknowledges and incorporates the uncertainty introduced by incomplete niche characterization. Then, we modify existing ancestral state inference methods to leverage full estimates of environmental tolerances. We provide a worked empirical example of our method, investigating ecological niche evolution in the New World orioles (Aves: Passeriformes: Icterus spp.). Temperature and precipitation tolerances were generally broad and conserved among orioles, with niche reduction and specialization limited to a few terminal branches. Tools for performing these reconstructions are available in a new R package called nichevol. 相似文献
139.
Yuanming Xiao Lucun Yang Xiuqing Nie Changbin Li Feng Xiong Lingling Wang Guoying Zhou 《Ecology and evolution》2020,10(13):6723-6731
Periodic climatic oscillations and species dispersal during the postglacial period are two important causes of plant assemblage and distribution on the Qinghai‐Tibet Plateau (QTP). To improve our understanding of the bio‐geological histories of shrub communities on the QTP, we tested two hypotheses. First, the intensity of climatic oscillations played a filtering role during community structuring. Second, species dispersal during the postglacial period contributed to the recovery of species and phylogenetic diversity and the emergence of phylogenetic overdispersion. To test these hypotheses, we investigated and compared the shrub communities in the alpine and desert habitats of the northeastern QTP. Notably, we observed higher levels of species and phylogenetic diversity in the alpine habitat than in the desert habitat, leading to phylogenetic overdispersion in the alpine shrub communities versus phylogenetic clustering in the desert shrub communities. This phylogenetic overdispersion increased with greater climate anomalies. These results suggest that (a) although climate anomalies strongly affect shrub communities, these phenomena do not act as a filter for shrub community structuring, and (b) species dispersal increases phylogenetic diversity and overdispersion in a community. Moreover, our investigation of the phylogenetic community composition revealed a larger number of plant clades in the alpine shrub communities than in the desert shrub communities, which provided insights into plant clade‐level differences in the phylogenetic structures of alpine and desert shrub communities in the northeastern QTP. 相似文献
140.
Bakhtiyor Sheraliev Sirojiddin Allayarov Zuogang Peng 《Zeitschrift fur angewandte Ichthyologie》2021,37(4):601-606
Alburnoides holciki Coad & Bogutskaya, 2012 was originally described to be found in the Hari River basin. So far, this species is known to occur in tributaries of the Hari River in Afghanistan, Iran and Turkmenistan, and also in the upper reaches of the Amu Darya in Tajikistan. Populations from the inland waters of Uzbekistan were previously considered as A. eichwaldii. Our study recognized specimens of Alburnoides from the inland waters of Uzbekistan as A. holciki based on both morphological data and the molecular data. The novelty of the study is the confirmation of A. holciki for the inland waters of Uzbekistan, which constitutes the northernmost record of this species. 相似文献