不同海拔温度和降水对新疆阿尔泰山西伯利亚落叶松径向生长的影响

为定量并分离关键气候因子对新疆阿尔泰山不同海拔树木径向生长的影响,通过对高、中和低海拔的西伯利亚落叶松(Larixsibirica)树轮宽度标准年表与气候因子分别进行相关、多元线性回归等统计分析,并进一步计算了线性模型中不同气候因素的绝对和相对贡献率。结果表明,高海拔地区,当年6月温度和上年7月降水分别与径向生长呈显著正相关和负相关,两者共同解释西伯利亚落叶松径向生长变异的33.1%,相对贡献率分别为66.2%和33.8%;中海拔地区,当年6月温度和上年6月降水分别与径向生长呈显著正相关和负相关,两者共同解释径向生长变异的26.8%,相对贡献率分别为40.1%和59.9%;低海拔地区,上年6月温度和7月降水分别与径向生长呈显著负相关和正相关,两者共同解释径向生长变异的29.4%,相对贡献率分别为31.9%和68.1%。这表明限制树木径向生长的主要影响因子随海拔的不同而异,在高海拔地区,温度是主要限制因子;而在低海拔地区,降雨是主要限制因子。     

阿尔泰山主要针叶树种树木径向生长及其对气候变化的响应

本研究以阿尔泰山富蕴地区的西伯利亚云杉和西伯利亚落叶松为对象,获取2个树种基部断面生长增量和树轮宽度年表与气候因子的相关系数,对比分析了相似生境下2个树种的径向生长特征及其对气候变化的响应。结果表明: 西伯利亚云杉基部断面生长增量总体高于西伯利亚落叶松,但西伯利亚落叶松的径向生长增加趋势更为显著。近60年来,上年快速生长期的高温对研究区内西伯利亚云杉的径向生长有限制作用,而当年6月较高的气温则有利于西伯利亚落叶松生长。西伯利亚落叶松的径向生长与当年1月气温呈负相关。分段相关分析显示,这种情况在1980年代中期气候变暖以后表现得更为明显。滑动相关分析表明,在气候变化背景下研究区内西伯利亚云杉和西伯利亚落叶松径向生长对气温和降水量的响应在近年来均有所增强。     

基于红松树轮重建小兴安岭南麓过去140年6月份平均温度变化

基于建立的小兴安岭南麓红松树轮宽度标准年表,分析红松径向生长与该地区温度和降水间的关系以及1982年升温突变对此相关性的影响。结果表明：6月平均温度与树轮宽度年表在变暖前后始终呈极显著负相关,是该地区红松径向生长的主要限制因子。基于此构建的区域1843—1982年6月平均温度重建方程稳定可靠。重建温度序列的偏暖时期和偏冷时期分别持续7年和29年,偏暖时段为1915—1921年,偏冷时段为1880—1891年和1932—1948年。小波分析结果显示6月平均温度存在2—7a周期变化。空间相关分析结果表明重建温度序列能很好的代表小兴安岭南麓及附近区域的温度变化。本研究拓展了研究区现有的气候数据,可为掌握小兴安岭气候变化规律和科学预测未来气候提供数据支撑。     

油松树轮指示的秦岭中部过去194年5—7月NDVI变化

由于归一化差异植被指数(NDVI)观测记录较短,对长时间尺度的NDVI变化研究较少,限制了我们对于全球变暖背景下气候驱动的植被生产力变化及其影响的理解。本研究利用陕西秦岭中部油松树轮样本建立区域树轮宽度指数年表,基于秦岭中部区域年表与5—7月NDVI的较高相关(r=0.624,P<0.01,n=34),利用线性回归模型重建秦岭中部1825—2018年5—7月NDVI变化,方差解释量为38.9%。空间分析表明,重建序列能够较好代表研究区范围内NDVI变化。重建序列表明,秦岭中部过去近194年经历了6个高值期和5个低值期,其中2006—2018年植被生长最好,即在最近的升温停滞期,秦岭中部植被生长呈显著恢复性生长。NDVI低值期与研究区区域干旱事件有着良好的对应关系。小波分析表明,重建序列存在2～4、12～16年准周期。SEA分析表明,重建序列在厄尔尼诺年出现显著下降,而在拉尼娜年事件发生后第1年至第3年出现显著上升。预测油松生长在SSP2-4.5、SSP3-7.0和SSP5-8.5情景下会略微上升。     

基于树轮宽度数据重建的阴山东部过去399年降水变化

基于阴山东部油松树轮样芯,建立采样区域树轮宽度年表,并计算器测时期(AD 1952—2007)月均温和月降水量与树轮宽度年表的相关系数。结果表明: 树轮宽度年表与上一年9月至当年6月降水量变化的相关性最高(r=0.73,n=56,P<0.01),基于此重建了阴山东部过去399年(AD 1619—2017)上一年9月至当年6月的降水量变化历史。该重建解释了器测时期上一年9月至当年6月降水量54.9%的方差,经“留一法”交叉验证和分段独立检验证明,重建方程稳定可靠。在年代际尺度上,过去399年存在4个湿润时期(AD 1619—1663、AD 1705—1711、AD 1945—1963和AD 1979—2017)和4个干旱时期(AD 1734—1767、AD 1786—1814、AD 1839—1867和AD 1888—1942)。其中,AD 1979—2017是最湿润的时期,而AD 1888—1942是干旱持续最长的时段,包含最干旱时期1920s晚期。功率谱分析显示,过去399年该区降水具有2～7年和125年准周期变化。通过与邻近区域重建对比及空间相关分析表明,本降水重建序列可以较好地代表研究区域的降水变化。     

Lower Cambrian (Botomian) polycystine Radiolaria from the Altai Mountains (southern Siberia, Russia)

Relatively well-preserved polycystine Radiolaria are here described from Lower Cambrian (Botomian) strata of the Shashkunar Formation, Altai Mountains in southern Siberia (Russia). These radiolarians display a test formed of a disorderly and three-dimensionally interwoven meshwork of numerous straight and curved bars branching from a five-rayed point-centered spicule located within the inner shell surface. The shell structure allows their assignment to the family Archeoentactiniidae, thus extending the known age range of the family down to the Lower Cambrian. The Botomian age is based essentially on trilobites (Parapagetia-Serrodiscus zone), but also on archaeocyathids identified in earlier publications. The study of the radiolarian-bearing sedimentary sequence confirms the presence of polycystine radiolaria in the external platform environments of Lower Cambrian ecosystems.     

Climate signal strength in tree-ring width of spruce growing in the Solovetsky Islands (Russia)

In this study we used 14 spruce tree-ring width local chronologies from sites that are located in different landscape conditions. The climatic response function for the entire period (116 years) shows that all local chronologies without exception have a positive relationship with June temperature (from 0.196 to 0.408) despite quite different local environmental conditions. This finding allowed us to combine all tree-ring width local chronologies into a composite spruce chronology covering the period of 1676–2016 CE with EPS exceeding the 0.85 threshold. The composite chronology was scaled against June air temperatures (CRU TS 4.01) in order to reconstruct it. Monthly air temperature records from the Arkhangelsk weather station were used as an additional source to validate tree-ring based June temperature reconstruction. It is quite remarkable that our reconstruction matches the Archangelsk records not only in the 20th-early 21st centuries but also in the 19th century, confirming the reliability of the reconstruction over more than two centuries. We also used daily records from the nearest Kem’-Port station to identify a more precise target-window. Current research shows that the spruce response to daily temperature is not limited by June, but also extends up to almost half of July. The warmest reconstructed year occurred in 1856 as confirmed by the data published in the local chronicle. The cooling recorded in the historical evidences (describing extremely severe ice conditions in the Arctic seas during the Great Northern Expedition (1733–1743)) was not corroborated by our reconstruction. In the study, we discuss the reasons of the discrepancies found between Solovki June temperature reconstructions and other data such as different seasonality of the compared records, real local climate warming in Solovki, the applied standardization technique, and low of chronologies’ replication. The most reliable part of the reconstruction part lasting from the early 19th to the early 21st centuries is also discussed in terms of its properties like wavelength analyses, and the assessment of influence of volcanic eruptions.     

Intra-annual radial growth of Schrenk spruce (Picea schrenkiana Fisch. et Mey) and its response to climate on the northern slopes of the Tianshan Mountains

Schrenk spruce (Picea schrenkiana Fisch. et Mey.) is widely distributed in the Tianshan Mountains. In this study, four Schrenk spruce trees were continuously monitored with dendrometers from 27 April to 30 September 2014 on the northern slopes of the Tianshan Mountains in northwest China. The goal of this monitoring study was to determine the main growing season of Schrenk spruce and to analyze intra-annual radial growth variability and its relation to daily meteorological factors. Our studies have shown that the critical growing season of Schrenk spruce is from late May to late July and that the rapid growth stage is from mid-June to early July. Meanwhile, in the growing season, changes in the radial growth of Schrenk spruce were negatively correlated with daily temperature, evaporation, sunshine hours and vapor pressure deficit (VPD), and were positively correlated with precipitation and relative humidity (RH). The correlation coefficient between radial growth and RH can be as high as 0.750 (Pearson, p < 0.0001, n = 60). Dates in which precipitation occurred corresponded to periods of rapid growth. The results of the climate-growth analysis show that changes in radial growth reflect the effect of water stress on tree growth, whether or not the changes are positively or negatively correlated with the above climatic factors. This indicates that moisture plays a major role in the growth of Schrenk spruce. We suggest that precipitation between late May to late June is a limiting factor for radial growth of Schrenk spruce on the northern slopes of the Tianshan Mountains.     

A new large chonetid (Brachiopoda) from the Middle Permian of the southern Kitakami Mountains, northeast Japan

A new chonetid genus and species, Kitakamichonetes multicapillatus gen. et sp. nov. (subfamily Chalimochonetinae, family Rugosochonetidae), from the Middle Permian (Wordian-Capitanian, Kanokura Formation) of the southern Kitakami Mountains (northeast Japan) is described.     

Dry/wet variations in the eastern Tien Shan (China) since AD 1725 based on Schrenk spruce (Picea schrenkiana Fisch. et Mey) tree rings

Cores of Schrenk spruce from seven sites of eastern Tien Shan were used to develop a regional tree-ring chronology to extend the climate record. We developed an August–July Standardized Precipitation Evapotranspiration Index (SPEI) reconstruction that spans AD 1725–2013 based on the regional tree-ring chronology. The reconstruction model accounts for 45.3% of the SPEI variance from 1959 to 2013. The SPEI reconstruction agrees reasonably well with the dry and wet periods previously estimated from tree rings in northern Xinjiang. The correlation analysis revealed that temperature plays an important role in regional drought variability, and some extreme wet years also coincide with the volcanic eruptions.     

Two new species of Panorpa (Mecoptera,Panorpidae) from the Hengduan Mountains in Yunnan,China

Two new species of the genus Panorpa Linnaeus, 1758 are described from the Hengduan Mountains in Yunnan, China. Panorpa diqingensis sp. n. can be distinguished from its congeners by vertex dark brown, and occiput yellow; pleura dark brown; gonocoxites bearing a cluster of stout black setae on inner apex; parameres S-shaped in male genitalia. Panorpa dispergens sp. n. can be readily differentiated from other Panorpa species by apical band with a hyaline spot in wings; gonocoxites with a cluster of stout dark brown setae and 3–5 long setae on inner apex; female medigynium with a pair of basal plates. The number of Panorpa species in Yunnan is raised to six. A key to Yunnan species of Panorpa is presented.     

中国云南高黎贡山园蛛属4新种记述(蜘蛛目:园蛛科)

本文记述了采自中国云南高黎贡山的园蛛属Amneus 4新种:春林园蛛,新种Amneus chunlin sp.nov.,李氏园蛛,新种Araneusliae sp.nov.,丰盛园蛛,新种Amneua plenus sp.nov.和亚坪园蛛,新种Araneus yapingensis sp.nov..模式标本正模及部分副模保存于湖南师范大学(HNU),部分副模将保存于美国加州科学学院(CaAS).文中量度单位为mm.     

Cytological study of Tibetia (Fabaceae) in the Hengduan Mountains region, China

The Hengduan Mountains comprise one of the world's most important hot spots of biodiversity. Tibetia (Ali) H.P. Tsui (Fabaceae), which has four or five species in two sections, is one of the genera endemic to the region. This paper describes for the first time the karyotype of three of those species. The chromosome counts of all three are 2n = 16. The karyotypes of the species examined contain chromosomes of variable karyotypic symmetry with centromeres at median and submedian positions that correlate with the morphological characteristics of the species. Karyotypic variation at the diploid level appears to be the predominant feature of chromosome evolution in the genus and may provide a clue to the study of evolutionary patterns of plants in this region. Received: June 12, 2001 / Accepted: September 12, 2001     

New radiolarians from the Devonian of the southern Ural Mountains: 1. Early-Middle Devonian (Late Emsian-Early Eifelian)

Late Emsian-Early Eifelian radiolarians from the southern Ural Mountains are recorded and described for the first time. They come from the Kamennaya Gora section on the Tanalyk River near the town of Buribay, Bashkiria. The new Late Emsian-Early Eifelian radiolarian assemblage consists of 20 species of 11 genera of spherical, discoidal, spindle-shaped, pylomate, and spiny radiolarians. Four new species, i.e., Entactinia rostriformis sp. nov., Palaeodiscaleksus tumefactus sp. nov., Primaritripus buribayensis sp. nov., and P. chuvashovi sp. nov., are described. The diagnosis of the genus Primaritripus Afanasieva, 2000 is amended. The fact that the oryctocenosis is dominated by discoidal radiolarians suggests that, in the Late Emsian-Early Eifelian, the area under study was occupied by a relatively shallow marine basin. Based on radiolarians, a new Upper Emsian-Lower Eifelian biostraton, beds with Primaritripus buribayensis-Entactinia rostriformis, is established. The history of the study of Early Devonian radiolarians is considered.     

Growing-season precipitation since 1872 in the coastal area of subtropical southeast China reconstructed from tree rings and its relationship with the East Asian summer monsoon system

Tree rings from temperate zones of the world have provided abundant palaeo- ecological and paleo-hydroclimatic information. However, tree rings from subtropical to tropical regions remain relatively scarce, which greatly limit our fully understanding about the climate change issues. In the present work, tree-ring-width (TRW) measurements of Masson pine from Fujian province, the coastal area of subtropical southeast China were successfully crossdated and a TRW STD chronology was developed from 1854 to 2012. Significantly positive correlation was identified between the tree rings and April–November total precipitation (r = 0.71, p < 0.01). The reconstructed April–November precipitation exhibited two comparatively wet (1876–1886 and 1957–1962) and one comparatively dry (1986–2004) periods. An evident drying trend since 1959 was seen and it was mitigated after 1993. Most of the extreme low-precipitation years in the reconstruction were supported by the historical records. As revealed by the spatial correlation patterns, our precipitation reconstruction was also consistent with other hydroclimatic records along the coastal areas of southeast China, proving its ability to capture the large-scale hydrological signal in southeast China (mainly refers to the south of the middle-lower reaches of Yangtze River). The reconstructed precipitation showed significant correlation with the East Asian summer Monsoon (EASM) index. Moreover, it also indicated simultaneous variation with the monsoon precipitation in North China on a decadal scale, implying that growing season precipitation variations in both regions were influenced by the EASM strength. This work highlights the potential of using tree-ring width to reconstruct precipitation in subtropical southeast China, while the relevant issues about precipitation variation in this region is far from resolved.     

Rugosochonetidae (Brachiopoda, Chonetidina) from the Carboniferous of the Cantabrian Mountains (N Spain)

An overview is given of the species belonging to the family Rugosochonetidae known from the Carboniferous of the Cantabrian Mts. Their distribution is compared with other occurrences in Eurasia and elsewhere. Subfamily and generic assignments are discussed in some detail. Comments on palaeogeographic and palaeoecological aspects of the rugosochonetid faunas are presented.     

Phylogenetic relationships of Eurasian Nuthatches (Sitta europaea Linnaeus, 1758) from the Alborz and Zagros Mountains,Iran

The Eurasian Nuthatch (Sitta europaea Linnaeus, 1758) is a resident bird in the Alborz and Zagros deciduous forests. We investigated the phylogenetic relationships and the taxonomic position of the Eurasian Nuthatch among other separated lineages of Eurasia with the help of blood samples collected from 19 individuals belonging to four populations in the Eastern and Western Alborz, as well as in the Northern and Southern Zagros forests. Genetic variation was then analysed using complete ND2 gene sequence (1041?bp) and phylogenetic analysis was done using Bayesian and maximum likelihood inference. Additionally, a median-joining algorithm was used to reveal the relationships among haplotypes. The results of the phylogenetic and haplo-type network analyses indicated that Eurasian Nuthatch haplotypes from the Alborz and Zagros Mountains form lineages distinct from the Asian, Caucasian and European haplotypes. Furthermore, an analysis of molecular variance (AMOVA) detected significant (P<0.001) genetic structure among the lineages. The Asian, European, Caucasian and Alborz lineages diverged from one another by an uncorrected genetic distance ranging from 0.029 to 0.039, while the Zagros lineage showed a slightly lower genetic divergence from the Caucasian lineage (0.006), but it did not share any haplotype with the Caucasian lineage. Thus, we suggest considering five Conservation Significant Units (CSU) for the Eurasian Nuthatches as the result of used dataset.     

Chromosome counts and karyotypes in Chaetoseris and Stenoseris (Asteraceae-Cichorieae) from the Hengduan Mountains of SW China

Chaetoseris and Stenoseris are two morphologically close genera from the tribe Cichorieae of the sunflower family and they are endemic in alpine eastern Himalayas to the Hengduan Mountains of SW China.Mitotic chromosome numbers and karyotypes are reported for 12 populations representing eight species of Chaetoseris and two species of Stenoseris from the Hengduan Mountains region.Eight species are new and the other two provide confirmation of previous reference.All Chaetoseris and Stenoseris taxa are diploidy with 2n ＝ 16 and their basic number is tentatively suggested as x ＝ 8.Karyotypes of Chaetoseris and Stenoseris are similar to each other with 2A and 2B for the former and 2A for the latter.Cytological data of chromosomal numbers and karyotypes support a close relationship of the two genera.Currently no polyploids are found for these two genera and it seems that polyploidization has played a minor role in their evolutionary speciation in the Hengduan Mountains region.