Lake Redó ecosystem response to an increasing warming the Pyrenees during the twentieth century

The ecosystem response of Lake Redó (Central Pyrenees) to fluctuations in seasonal air temperature during the last two centuries was investigated by comparison of reconstructed air temperatures with the sediment record. Fine slicing allowed a resolution of 3–6 years according to the ²¹⁰Pb dating, although it was still difficult to easily investigate the response to air temperature forcing, since extreme fluctuations in temperature occur on interannual time-scales. However, the resolution was sufficient to show responses on decadal and century scales. An overall tendency to warming in mean annual temperature in the Central Pyrenees has been caused by summer and in particular by autumn increases. Many of the measured sediment variables apparently responded to these long term trends, but the significance of the relationships was highly conditioned by the structure of the data. The variables responding most on the finer time scales were the microfossils. For diatoms, chironomids and chrysophytes the main variability correlated to summer and to autumn temperatures. For two planktonic species, Fragilaria nanana and Cyclotella pseudostelligera, we found a link of their variability with temperature fluctuations in their growing months (September and October, respectively). This relationship appeared at a certain point during a general warming trend, indicating a threshold in the response. On the other hand, no significant changes in the dominant species could be linked to temperature, nor in any significant subgroup of the 180 diatom species present in the core. In contrast, for most chironomids (particularly Paratanytarsus austriacus, Heterotrissocladius marcidus and Micropsectra radialis) a negative relationship with summer temperature extended throughout the studied period. This response of the whole group gives chironomids a more robust role as indicators for recording temperature changes on long time-scales (e.g., through the Holocene) and for lake signal inter-comparison. Finally, our results indicated that, in all cases, there was a significant resilience to high frequency changes and hysteresis despite extreme fluctuations. Although we were dealing with organisms with one or many generations per year, their populations seemed to follow the decadal trends in air temperature.     

关于“豹皮灰岩”的成因

襄汾县浪泉乡中奥陶统马家沟组灰岩中豹皮灰岩的豹斑是虫孔内的碳酸盐物质在成岩期经白云岩化作用而成,在碳酸盐沉积物的形成和改造过程中,生物起了巨大作用。豹斑的整体形状保留了遗迹化石的形态。     

Two-Year Observation of Fossil Fuel Carbon Dioxide Spatial Distribution in Xi'an City

The need for atmospheric carbon dioxide(CO_2) reduction in the context of global warming is widely acknowledged by the global scientific community.Fossil fuel CO_2(CO_(2ff)) emissions occur mainly in cities,and can be monitored directly with radiocarbon(~(14) C).In this research,annual plants [Setaria viridis(L.) Beauv.] were collected from 26 sites in 2013 and2014 in the central urban district of Xi'an City.The △~(14)C content of the samples were analyzed using a 3 MV Accelerator Mass Spectrometer,and CO_(2ff) concentrations were calculated based on mass balance equations.The results showed that the CO_(2ff) mixing ratio ranged from 15.9 to 25.0 ppm(part per million,equivalent to μmol mol~(-1)),with an average of 20.5 ppm in 2013.The range of measured values became larger in 2014,from 13.9 ppm to 33.1 ppm,with an average of 23.5 ppm.The differences among the average CO_(2ff) concentrations between the central area and outer urban areas were not statistically significant.Although the year-to-year variation of the CO_(2ff) concentration was significant(P 0.01),there was a distinctly low CO_(2 ff) value observed in the northeast corner of the city.CO_(2 ff) emiissions from vehicle exhaust and residential sources appeared to be more significant than two thermal power plants,according to our observed CO_(2 ff) spatial distribution.The variation of pollution source transport recorded in our observations was likely controlled by southwesterly winds.These results could assist in the optimal placement of regional CO_2 monitoring stations,and benefit the local government in the implementation of efficient carbon emission reduction measures.     

中国人类化石研究对古人类学的贡献

中国人类化石研究为古人类学增添大量具体资料,并且促进了人类进化理论的发展。北京直立人化石的研究将人类的化石记录肯定地推前到0．50MaB．P。对大量化石的研究将中国人类进化归纳为“连续进化附带杂交”的模式。这是对近年古人类学两大热点之一的现代人起源争论中关于东亚现代人来源的一项重要的贡献。此外,中国人类化石的研究还揭示在各个时期中中国的古人类存在明显的地区间差异。     

Dating of detrital zircon grains and fossils from Late Palaeozoic sediments of the Baruo area,Tibet: constraints on the Late Palaeozoic evolution of the Lhasa terrane

ABSTRACT

To determine the Late Palaeozoic evolution of the Lhasa terrane, we report the results of field mapping, petrological and fossil investigations, and U–Pb dating of detrital zircon grains (n = 474) from lower-greenschist-facies clastic rocks of the Lagar Formation in the Baruo area, Tibet. Our results indicate that the Lagar Formation was deposited during the Late Carboniferous to Early Permian in a shallow-marine environment on the northern margin of Gondwana. Glacial marine diamictites are common within the Lagar Formation and record glaciation of Gondwana during the Late Palaeozoic. Moreover, the detrital materials of the Lagar formation originated mostly from the collision orogenic belt. The ages of detrital zircon grains from the Lagar Formation make up five main groups with ages of 410–540 Ma, 550–650 Ma, 800–1100 Ma, 1600–1800 Ma, and 2300–2500 Ma, which display three characteristic age peaks at ~1150, 2390 and 2648 Ma. We tentatively suggest that the Lhasa terrane was a shallow-marine basin under the influence of the Gondwanan glaciation during the Late Carboniferous–Early Permian.     

Neogene Billa Kalina Basin and Stuart Creek silicified floras,northern South Australia: a reassessment of their stratigraphy,age and environments

Abstract

Silicified fossil macrofloras of the Willalinchina Sandstone, at Stuart Creek in the Billa Kalina Basin of northern South Australia, are most likely early Miocene–early Pliocene with preference for the younger age, based on reinterpretation of published evidence including basin stratigraphy, paleogeography, isotopic and other dating. The macrofloras include Eucalyptus and occur in fluvial channel sandstones. The Willalinchina Sandstone is equated with the Danae Conglomerate Member of the Mirikata Formation, interpreted as older than the Watchie Sandstone, Millers Creek Dolomite Member and Billa Kalina Clay Member, and here regarded as of upper Neogene age. The Billa Kalina Basin lies between Lake Eyre, Torrens and Eucla basins, and has affinities with all three. The Kingoonya Paleochannel, peripheral to the Eucla Basin, joins the southern margin of the Billa Kalina Basin across the Stuart Range Divide, and contains the Garford Formation of mid-Miocene to Pliocene age (palynological dating), here partly equated with the Mirikata Formation. Interpretations of paleolake Billa Kalina and associated paleochannel environments are made, based on a new assessment of stratigraphic and paleogeographic relationships.

1. KEY POINTS

2. The Billa Kalina Basin sediments in northern South Australia are equated with the later Neogene ‘upper’ Garford Formation of the Kingoonya Paleochannel, which flowed into the Eucla Basin, and depositional processes are clarified.

3. A variety of consistent age data from adjacent basins and the Kingoonya Paleochannel indicate the Stuart Creek ‘silcrete floras’, associated with the Willalinchina Sandstone channel deposits, are Neogene, probably early Pliocene, but the possibility remains that they may be incised into the Watchie Sandstone and therefore late Pliocene.

4. The Billa Kalina Basin was linked to the Kingoonya Paleochannel through much of its history, with flow disrupted by the Stuart Range Divide, local tectonics, and regional tilting.

     

柯克亚凝析气田中新统西河甫组季节性河流沉积特征研究

柯克亚凝析气田中新统西河甫组在沉积特征上与正常的曲流河相比较为相似，如具有较典型的二元结构、中等砂岩成熟度、两段式的概率累积曲线、以单向水流为主的牵引流占主导地位的沉积构造等，同时也具有一些特殊性：①未发现有植物根迹，也没有含煤地层出现，在河漫滩亚相中缺少沼泽微相。②存在异常水流活动以及指示洪水重力流作用存在的沉积构造；③存在能反映氧化、河流季节性活动以及干旱气候环境的丰富而独特的遗迹化石组合，如Scoyenia组合和Skolithos组合等，上述特征反映其为干旱气候下的季节性河流沉积。     

滇中妥甸组中首次发现昆虫化石

首次在云南滇中地区晚侏罗世妥甸组滥泥阱剖面和级山坡一带发现昆虫化石2新种：Mesobluttula tuodianensis sp.nov.和Neorthophlebia yunnanensis sp．nov．，未定种3种。其中长翅目新直脉蝎蛉新直脉蝎蛉属(Neorthophlebia)在国内为首次发现。     

A new middle to late Eocene continental chronostratigraphy from NE Spain

The calibration of the European Paleogene mammal biochronology with the international reference geochronological scale is unconstrained due to the lack of direct marine-continental correlations and insufficient robust magnetostratigraphic data for mammal fossil-bearing sequences. The currently accepted European continental biochronology argues for a correlation of the Paleogene MP14 to MP16 mammal reference levels with the Bartonian stage, and of the MP17 to MP20 levels with the Priabonian. However, new magnetostratigraphic data of the continental sediments of the south-central Pyrenees substantially challenge this chronology. Our new results from the La Pobla de Segur Basin and Sierra de Sis have been integrated into the framework of previous marine-continental stratigraphic correlations and magnetostratigraphic data of the south-central Pyrenees. In this new chronology, MP14 and MP15 reference levels correspond to the Lutetian, whereas MP16 and early MP17 correlate with the early Bartonian. This calibration represents a significant revision of currently accepted marine-continental correlations in Europe, but is not in conflict with the available biostratigraphic data of the south Pyrenean Ebro foreland basin and other western European reference basins.     

Institutional interaction to address greenhouse gas emissions from international transport: ICAO, IMO and the Kyoto Protocol

In response to Article 2.2 of the Kyoto Protocol, the International Maritime Organisation (IMO) and the International Civil Aviation Organisation (ICAO) have begun to consider greenhouse gas (GHG) emissions from international aviation and shipping. However, neither ICAO nor IMO have taken any effective action on the issue yet and progress can be characterised as slow. The lack of action has so far not been made up for by measures within the climate change regime or by individual countries. An important motivation for the efforts of ICAO and IMO so far has been the potential regulatory competition with the climate change regime. However, given the lack of political will to act on the issue within the latter, this motivation has not been very forceful. Against this backdrop, I argue that there are in particular three options for furthering progress within ICAO and IMO, namely (1) enhancing the threat of regulation of GHG emissions from international transport under the climate change regime; (2) undertaking unilateral domestic action by various countries (in particular the EU); and (3) furthering a learning process within ICAO and IMO. Furthermore, a closer coordination of efforts under ICAO, IMO and the climate change regime could facilitate and accelerate progress.