Tectonic and sedimentary evolution of basins in the northeast of Qinghai-Tibet Plateau and their implication for the northward growth of the Plateau

The northeast of the Qinghai-Tibet Plateau, from the Hoh Xil Basin to the Hexi Corridor Basin, demonstrates a basin-ridge geomorphy that is the result of the long-term uplift of the Qinghai-Tibet Plateau. The geological evolution of the Qinghai-Tibet Plateau is recorded in its associated basins. From the Cenozoic sedimentary filling pattern in the Hoh Xil, Qaidam and Jiuquan Basins, we find that the evolution of these basins is similar: they began as strike-slip basins, evolved into foreland basins, and then to intermontane basins. Foreland basins are the direct result of orogenic activity in the northeast of Qinghai-Tibet Plateau, and can be documented to have formed over the following time periods: 49-23 Ma for the Hoh Xil foreland basin, 46-2.45 Ma for the Qaidam foreland basin, and 29.5-0 Ma for the Jiuquan foreland basin. This northward migration in the timing of foreland basin development suggests that the northeastern part of Tibet grew at least in part by accretion of Cenozoic sedimentary basins to its northern margin.     

Genetic structuring in the freshwater mussel Anodonta corresponds with major hydrologic basins in the western United States

Freshwater mussels (unionids) are increasingly recognized as important providers of ecosystem services, yet are among the most endangered fauna in the world. Because unionids are generally sessile and require specific fish hosts for development and dispersal, they are particularly vulnerable to habitat degradation. Surprisingly, little is known about the distribution of genetic diversity in freshwater mussels and this gap has a negative impact on taxonomy, monitoring, conservation and ecological research in these species. Here, we focus on western North American Anodonta, one of only three genera known to exist in this broad landscape and which contains three highly divergent lineages. We describe phylogeographical subdivision in the most widespread and diverse of these lineages, which includes Anodonta californiensis and Anodonta nuttalliana and occurs from Canada to Mexico. Using mitochondrial and nuclear data, we found that genetic structuring within this clade is inconsistent with morphologically based species designations, but instead follows patterns of vicariance among major hydrogeologic basins. Furthermore, there was a strong tendency for population diversity within drainage systems to increase downstream, implying greater habitat or host fish availability in this direction. Microsatellite results indicated that sampling locations were all genetically distinct, even at short distances. Many of our sample populations showed evidence of a recent demographic bottleneck, although this effect seemed to be very local and not drainage or basin‐specific. This study provides a foundation for the establishment of appropriate management units and future research on adaptive differentiation and host fish relationships.     

从微体化石群看我国沿海早第三纪含油盆地的差异

对我国沿海3个含油盆地－珠江口、北部湾和渤海湾盆地下第三系湖相生油岩中的微体化石群进行比较分析。3个盆地中以渤海湾盆地下第三系湖相化石群最为丰富,数量多,分异度高,而且化石群以地方性属种比例高、咸水类型多,存在“海源陆生生物化石”为特征;北部湾盆地,在涠洲组和流沙港组发现较多的介形类化石及个别腹足类和轮藻化石;而珠江口下经三系湖相地层中,微体化石罕见,只在个别层位发现贝壳碎片。据化石群特征,推测渤海湾盆地早第三纪是封闭型的咸水湖泊,而且部分沉积时期,可能是以Cl^-和Na^ 为主的咸水湖泊;珠江口盆地早第三纪是湖水矿化度低、硬度、pH值也低的淡水湖泊;而北部湾盆地早第三纪可能仍属淡水湖泊,但有一定的矿化度。     

Eocene and Oligocene chitons (Polyplacophora) from the Paris and Hampshire Basins

Eocene and Oligocene chitons (Polyplacophora) from the Paris Basin of N France are described along with comparative material from the Hampshire Basin of the UK. The assemblages include eight species, five of which are new: Ischnochiton fehsei sp. nov., Stenoplax monila sp. nov., Chaetopleura gaasi sp. nov., C. abbessi sp. nov. and Tonicella lira sp. nov. Other taxa in the assemblages are Leptochiton cf. algesirensis, I. vectensis and S. anglica.     

Clarifying an ambiguous evolutionary history: range‐wide phylogeography of an Australian freshwater fish,the golden perch (Macquaria ambigua)

Aim We conducted a range‐wide phylogeographic study of a common Australian freshwater fish, the golden perch (Macquaria ambigua), to investigate the relationship between environmental processes and evolutionary history in drainage basins. Location Inland [Lake Eyre (LEB), Murray–Darling (MDB) and Bulloo (BULL)] and coastal basins [Fitzroy (FITZ)] of eastern Australia. Methods A total of 590 samples were collected from across the entire species’ distribution and a section of the mitochondrial DNA control region was sequenced. In order to reconstruct the evolutionary history of M. ambigua a comprehensive suite of phylogeographic analyses was conducted, including nested clade phylogeographic analysis, mismatch analysis and isolation‐with‐migration model simulations. Results Three major lineages corresponding to the major drainage basins, FITZ, MDB and LEB/BULL, were identified (Φ_ST = 0.92). Lineages from the coastal basin (FITZ) were highly divergent from those of the inland basins (up to 6%). Levels of genetic diversity in the inland basins were relatively low and our analyses indicate that these populations experienced both demographic and range expansions during the Pleistocene. Main conclusions Investigation of the range‐wide phylogeography of M. ambigua has revealed new insights into the biogeography of the Australian arid zone, particularly with regard to evolutionary events chronologically associated with cyclical moist and dry conditions. We propose that M. ambigua originated on the east coast (FITZ) and crossed a major geographic barrier, the Great Dividing Range (GDR), to colonize the inland basins (MDB, LEB and BULL). We infer a series of demographic and range expansion events for M. ambigua consistent with a scenario of moister Pleistocene conditions and increased connectivity of freshwater environments, both within and among drainage basins. Major lineages then diversified following isolation of freshwater environments under increasingly arid climate conditions. We suggest that management priorities for M. ambigua should include the resolution of taxonomic uncertainties and the maintenance of genetic diversity of both stocked populations in the MDB and native populations of the LEB that may be at risk of further isolation and reduced gene flow due to increased aridification under future climate change scenarios.     

Lacustrine basin to delta evolution in the Zagorje Basin,a Pannonian sub-basin (Late Miocene: Pontian,NW Croatia)

Pontian deposits of the Zagorje Basin constitute a coarsening-upward succession, which reflects the infilling style of this Pannonian sub-basin, i.e. the progradation of clastic systems into the brackish lake. Six facies differentiated correspond to lake floor, channelled slope, distal and proximal pro-delta, distal and proximal mouth bars, and lagoon/bay to swamp and alluvial environments. The deposition in the mouth-bar area was dominated by frictional forces. The upper-stage plane-bed sands are the main mouth-bar facies, which is uncommon in the geological record. The main factors for the origin of such bars include an abundant sand supply by the high-energy fluvial system(s), low-energy of the receiving basin and shallow depositional depth. Prolonged, catastrophic floods generated sustained hyperpycnal flows, which bypassed the mouth-bar area and fed the slope/pro-delta. The high ratio between sediment supply and subsidence rate resulted in a fast moving progradational wave, which involved the entire SW Pannonian Basin, including the Zagorje Basin.     

泥河湾盆地旧石器文化研究新进展

泥河湾盆地旧石器文化异常丰富,在约1800平方公里范围内新发现各时期的旧石器文化遗址或地点三十余处,这些发现为该盆地旧石器文化研究提供了大批的科学资料。盆地内小石器文化传统贯穿始终,从早到晚旧石器有明显的继承性和发展性。到旧石器时代晚期,同时存在细石器技术传统的产品。     

Large theropod trackway from the Lower Jurassic Zhenzhuchong Formation of Weiyuan County,Sichuan Province,China: Review,new observations and special preservation

The well-preserved theropod track Weiyuanpus zigongensis, recently assigned to Eubrontes zigongensis, was not described in exhaustive detail at the time of its original discovery in 2007. Among the morphological details not described was an antero-medially directed hallux seen in five of the six tracks that make up the type trackway. Hallux traces are only rarely reported in large Lower Jurassic theropod tracks such as Eubrontes and Gigandipus, and their presence or absence may be the result of one or both of two factors: track depth and/or differences in hallux configuration in the trackmakers. Here we argue that E. zigongensis is one of the best preserved examples of a eubrontid track, which can be morphologically distinguished from other Eubrontes ichnospecies by the presence of well-defined hallux traces.     

Elemental variation in the termite fishing of wild chimpanzees (Pan troglodytes)

Chimpanzee tool behaviours vary dramatically in their complexity and extent of geographical distribution. The use of tool sets with specific design features to gather termites extends across a large portion of central Africa. Detailed examination of the composition and uniformity of such complex tool tasks has the potential to advance our understanding of the cognitive capabilities of tool users and processes underlying the maintenance of technological skills. In this study, we examined variation in chimpanzee tool use in termite gathering from video-recorded sequences that were scored to the level of functionally distinct behavioural elements. Overall, we found a high degree of similarity in tool-using techniques exhibited by individuals in this population. The number of elements in each individual's repertoire often exceeded that necessary to accomplish the task, with consistent differences in repertoire sizes between age classes. Adults and subadults had the largest repertoires and more consistently exhibited element strings than younger individuals. Larger repertoires were typically associated with incorporation of rare variants, some of which indicate flexibility and intelligence. These tool using apes aid us in understanding the evolution of technology, including that of our human ancestors, which showed a high degree of uniformity over large spatial scales.     

黄河三花间年径流量变化规律

利用1956--2007年黄河中游三门峡-花园口区间(简称"三花间"区)4个水文站的实测年径流量资料,采用趋势分析、小波分析等统计方法,探讨了三花间区年径流量的变化特征.结果表明:三花间年径流量的总体变化呈减少趋势;年径流量大体上经历了2个丰水阶段和2个枯水阶段的交替变化,转折点出现在1969、1982和1987年;年径流量的时频变化则以25 a或2～8 a的周期变化为主.     

洱海流域水生态分区

分区边界的确定是生态分区的重要步骤,但目前多数水生态分区的边界确定以定性分析、专家判断为主。本研究以洱海流域为例,建立了一套两级分区体系。该体系基于GIS技术,用子流域作为分区基本单元,并用相关分析法,定量筛选一、二级分区指标。其中,一级分区指标为高程、坡度和植被归一化指数(NDVI),二级分区指标为农田百分比和城镇百分比。通过指标图层的叠加和重分类,合并同质性子流域,从而将洱海流域划分为5个一级区和9个二级区。藻类群落分布的验证结果表明分区合理。本研究将定量分析和子流域边界应用于水生态分区,使分区边界的确定更科学,在实际管理中更具有可操作性。本研究结果为水生态分区研究提供了新的方法,为洱海流域水生态管理提供了基本管理单元。     

Marinitoga lauensis sp. nov., a novel deep-sea hydrothermal vent thermophilic anaerobic heterotroph with a prophage

A novel moderately thermophilic, heterotrophic anaerobe, designated strain LG1^T, was isolated from the Mariner deep-sea hydrothermal vent field along the Eastern Lau Spreading Center and Valu Fa Ridge. Cells of strain LG1^T were motile rods, occurring singly or in pairs, 0.6 μm in width and 1.2 μm in length. The strain LG1^T grew between 40 and 70 °C (optimum 50–55 °C), at a pH between 5 and 8 (optimum pH 6.5) and with 7.5–50 g L⁻¹ NaCl (optimum 30 g L⁻¹). Sulfur, cystine and thiosulfate were reduced to sulfide, and cell yield was improved in the presence of cystine. Strain LG1^T was an organotroph able to use a variety of organic compounds. Phylogenetic analysis based on 16S rRNA gene sequence comparisons indicated that strain LG1^T was affiliated to the genus Marinitoga within the order Petrotogales. It shared 95.34–96.31% 16S rRNA gene sequence similarity with strains of other Marinitoga species, and is most closely related to Marinitoga okinawensis. Genome analysis revealed the presence of a prophage sharing high sequence homology with the viruses MPV1, MCV1 and MCV2 hosted by Marinitoga strains. Based on the data from the phylogenetic analyses and the physiological properties of the novel isolate, we propose that strain LG1^T is a representative of a novel species, for which the name Marinitoga lauensis sp. nov. is proposed; the type strain is LG1^T (=DSM 106824 = JCM 32613).     

柴达木盆地渐新世的鲤科鱼类化石

记述了首次发现于柴达木盆地早渐新世晚期至晚渐新世早期(距今27～29 Ma)的鲤科鱼类化石。材料包括咽骨、咽齿、匙骨、腹鳍骨及一些零散的鳍条。咽骨及咽齿化石与原始鲃亚科鱼类及裂腹鱼亚科裂腹鱼属鱼类的相似;腹鳍骨化石与原始鲃亚科鱼类的更相似。鲃亚科鱼类现今分布于北纬35°以南的亚洲、欧洲南部及非洲北部;裂腹鱼属鱼类分布局限于青藏高原东、南、西面的边缘区域,在柴达木盆地没有分布。柴达木盆地水系现生鱼类仅见适于高寒环境的高度特化等级的裂腹鱼亚科鱼类及鳅科高原鳅属鱼类,鱼类组成与早渐新世晚期至晚渐新世早期的不尽相同。     

First afrosoricid out of Africa: an example of Pliocene ‘tourism’ in Europe

The afrosoricids are an endemic order exclusively from Africa with a very scarce fossil record. In this work, we present the first record outside this continent. The “otter shrew” Europotamogale melkarti n. gen. n. sp. was found in the Moreda 3 karstic fill site in Granada (Spain), of MN15 age (mid-Pliocene). This new taxon confirms the semiaquatic faunal interchange between Europe and Africa. We hypothesize that this tenrecid, representative of a family frequently present in the Central African faunas, migrated to the north of the continent via the Sahabi river system that connected North and Central Africa. Europotamogale n. gen. is the first known afrosoricid that migrated between the two continents. It was present in Europe for a very short time (as a ‘tourist genus’). To date, this phenomenon has only been described in genera of European origin, such as the pika Prolagus or the mouse Apodemus.     

A New Ichnospecies of Arthrophycus from the Late Carboniferous (Pennsylvanian) of Michigan,USA

A unique ichnofossil assemblage from Pennsylvanian-age sandstones near Eaton Rapids, Michigan, USA, comprises straight-to-curved traces preserved in convex hyporelief, with the transverse ridges and median grove associated with the ichnogenus Arthrophycus. The Michigan traces show some branching or pseudo-branching (also known from other Arthrophycus specimens) and are among the smallest structures (millimeters in diameter) attributed to this ichnogenus. The orientation of the Michigan Arthrophycus burrows is distinct from other ichnospecies of this taxon in the pronounced co-planar alignment of the burrows, as opposed to the multiplanar, interweaving, “bundled” nature typical of the ichnogenus. On this basis we assign the Michigan specimens to a new ichnospecies of Arthrophycus. The “paralleling behavior” of the new taxon may reflect a strategy of the tracemaker to avoid previous burrows and reflect differences in resource availability or current energy. This new taxon supports previous records of the occurrence of this ichnogenus in Upper Carboniferous strata.     

陕甘宁盆地二马营组的假鳄类

在陕甘宁盆地东北缘二马营组发现的两种假鳄类,经鉴定均属Euparkeridae。其中之一与Euparkeria较相近;根据肩胛骨、肱骨和骨质背板等的显著不同,定名为侨家梁哈拉寨鳄(Halazhaisuchus qiaoensis),新属、新种。依据骨髂形态,另一标本归入世鲁番鳄属(Turfanosuchus),取名沙圪堵吐鲁番鳄(Turfanosuchus shageduensis)、新种。     

记兰州盆地第三纪中期的爪兽(奇蹄目)化石

记述了兰州盆地新发现的三种爪兽化石：Schizotheriumordosium,Phyllotillonhuangheensissp．nov．和Chalicotheriinae亚科未定属种的一类。在咸水河组下段南坡坪地方动物群（早渐新世晚期）中发现S.ordosium。这个种的材料较多,其中有保存完好的下颌吻部。这使我们第一次了解了这个属的吻部的构造：吻部很长、具大的铲形下门齿和双叶形的下犬齿．在咸水河组中段（早中新世）张家坪地方动物群中发现了Phyllotillonhuangheensis和Chalicotheriinaegen．etsp．indet。前者比巴基斯坦Bugti层中的P.naricus个体稍小,形态上也更原始些。这可能表明,张家坪地方动物群在时代上比Bngti稍早。后一类爪兽的性质还不很清楚,但Chalicotheriinae亚科在我国早中新世的出现则无疑义。     

新疆玉龙喀什河与策勒河流域胡杨年轮对气象因子的响应研究

在树木年轮学与气候学理论基础上,以新疆和田地区玉龙喀什河与策勒河下游河岸胡杨为研究对象,基于流域对应的气象、沙尘天气日数、策勒河径流量等因子,分析了玉龙喀什河与策勒河流域胡杨年轮对气象因子的响应特征,以明确干旱荒漠区胡杨生长过程中的气候限制因子,为促进胡杨生态修复及沙尘防治提供理论依据.结果显示:(1)1976-201...