Carbon-13 in black sea waters and implications for the origin of hydrogen sulfide

A combination of measurements of carbon-13 and the hydrogen sulfide content in Black Sea waters with available data on the total carbon dioxide in these waters indicates that the contribution of organic sulfur to the hydrogen sulfide lies between 3 and 5 percent and increases with depth. Likely causes for the increase are increasing productivity or upward movement of the anoxic zone during the facts last 2000 year.     

Black sea: recent sedimentary history

Three distinct sedimentary units, which can be correlated throughout the basin, occur in cores collected from the Black Sea. Carbon-14 ages help to define the recent sedimentary history of the Black Sea.     

ARCHAELOGY: A Victim of the Black Sea Flood Found

Archaeologists are mulling over tantalizing images of what appears to have been a house of wood and mud littered with human artifacts now 91 meters beneath the Black Sea. The find lends further credence to the claims of two oceanographers that a torrent equaling 200 Niagara Falls cascaded from the Mediterranean Sea 7500 years ago, driving Neolithic peoples living along the Black Sea coastline inland. But whether the catastrophe gave rise to the biblical account of Noah's Flood and spread farming into central Europe, as the researchers speculate, we can't yet say.     

The Beginnings of Metallurgy: A New Look: Arguments over diffusion and independent invention ignore the complex metallurgic crafts leading to iron

In the 9 years since my first survey of early metallurgy appeared in this journal (65) metallurgy has become a major battleground between those who argue independent invention and those who argue diffusion in the evolution of urban civilization. In this new article I contend that: 1) The upland belt and debouching river valleys of southwestern Asia have a clear priority in the beginnings of copper metallurgy and extractive metallurgy generally, suggesting that the forces of urbanization contributing to the rise of metallurgy there were more massive, widespread, and better integrated than elsewhere. 2) The trend to polymetallism, against the background of pyrotechnology generally and the other important technologies of urbanism, established a necessary sequence to early metallurgy. This sequence was a prerequisite to the coming of the Iron Age, which was uniquely contained at first within the environment of Anatolia and the eastern Mediterranean and spread outward from there. 3) The course of metallurgy and possibly of the other urbanizing technologies can best be understood through a process of diffusion and multiple innovation interrelating metallurgical evolution over much of Eurasia, but with the area defined by the Black Sea, the Caspian Sea, the Red Sea, and the eastern Mediterranean as its center. Only in this fashion can we place metallurgy in its proper role as an important subsystem in the rise of civilization.     

GIS在管道工业中的应用

介绍了GIS数据库及从地图、航空照相、卫星遥感获得GIS数据的三种方法及管道工业成功应用GIS的两个事例。美国的西北天然气公司利用GIS使其许多工作自动化,如计算机辅助泄漏检查、管网模型分析、紧急事故响应和系统规划等,GIS已使该公司的工作环境远远超过CAD时代。Bechtel公司在铺设从里海到黑海的原油输送管道时,利用GIS和卫星遥感建立一个最小费用线路的计算机模型。结果表明,利用GIS软件的地面覆盖自动辨别能力和遥感卫星生成的地面覆盖地图建立的线路模型选线,将比在里海与黑海之间采用直线线路的费用少14%。     

7000 years of Emiliania huxleyi viruses in the Black Sea

A 7000-year record of Coccolithovirus and its host, the calcifying haptophyte Emiliania huxleyi, was reconstructed on the basis of genetic signatures preserved in sediments underlying the Black Sea. The data show that the same virus and host populations can persist for centuries. Major changes in virus and host populations occurred during early sapropel deposition, ~5600 years ago, and throughout the formation of the coccolith-bearing sediments of Unit I during the past 2500 years, when the Black Sea experienced dramatic changes in hydrologic and nutrient regimes. Unit I saw a reoccurrence of the same host genotype thousands of years later in the presence of a different subset of viruses. Historical plankton virus populations can thus be included in paleoecological and paleoenvironmental studies.     

乐清湾海域鱼类中多溴联苯醚的分布特征

使用气相色谱-质谱-化学离子源（GC—MS-NCI）检测法对持久性有机污染物多溴联苯醚（PBDEs）的10种同系物（∑10PBDEs）在海洋鱼类（红鲈、黑鲷、鲈鱼）中的含量进行了检测。结果表明,红鲈、黑鲷、鲈鱼肌肉中∑10PBDEs的含量分别为252．6～662．2、454．6～1413．4、147．4-760．5ng／kg湿重（ww）。鱼肌肉样品中BDE47的相对含量最高。鱼肝对多溴联苯醚的富集能力强于鱼肉。     

Copper porphyrins in deep-sea sediments: a possible indicator of oxidized terrestrial organic matter

Copper porphyrins have been isolated from deep-sea sediments collected during six legs of the Deep Sea Drilling Project-International Program of Ocean Drilling. These pigments are present in depositional areas receiving high inputs of terrestrially derived oxidized organic matter. Such areas include the Black Sea, the Bay of Biscay, the Blake-Bahama Basin, and slumped Miocene deposits off Cape Bojador on the west coast of Africa.     

29 种绿化树木叶片含硫量分析

为了揭示濮阳常见道路绿化树种叶片含硫量的差异性,于2011年春、夏、秋季对市区不同路段29种绿化树木的叶片含硫量进行比较,结果表明:不同季节部分树种叶片含硫量差异显著,除了大叶女贞和侧柏外,大多数树种叶片含硫量随春、夏、秋季节的变化基本呈现递增趋势.根据全年29种树木叶片平均含硫量大小进行分类,毛白杨和圆柏含硫量较高,归为第1类;黑松、桂花、悬铃木和银杏叶片含硫量居中,归为第2类;泡桐、楝树、火棘、红叶李、榆树、合欢、垂柳、大叶女贞、银白杨、紫薇、杨树、侧柏、小叶黄杨、刺槐、雪松、白蜡、广玉兰、栾树、红叶石楠、海桐、构树、大叶黄杨和国槐叶片含硫量相对较低,归为第3类.     

路易斯安娜鸢尾品种引进及种苗生产研究

[目的]对引进的8个路易斯安娜鸢尾品种的物候期、生长特性、结实性、分生能力等进行观察测定。[方法]8个品种分别为‘B1ackGamecock’、‘RegalRicochet’、‘Teven’、‘SeaWisp’、‘WaihiWedding’、‘HotAndSpicy’、‘SeriouslyBlue’和‘Gunner’。[结果]8个引进品种在苏州均能正常开花,叶片冬季绿色,品种间在花期、花色、花茎高度等方面的差异为园林应用提供了丰富的植物材料;5个品种人工授粉后,大田开放授粉植株的结实率高于设施内隔离授粉的植株,‘SeaWisp’结实率最高达70．4％,可用于实生苗生产;‘BlackGamecock’品种在大田自然生长环境中分生系数最高达9,可用于分生苗生产;‘HotAndSpicy’不结实,分生系数低,需要依靠组培方式生产种苗。[结论]根据品种的不同特性选择不同种苗生产途径,可为苏州地区种苗生产提供参考。     

葡萄芽自然休眠期间的呼吸代谢变化

【目的】探讨葡萄芽呼吸代谢与自然休眠解除的关系,为葡萄人工休眠调控技术措施的制定提供理论依据。【方法】以高需冷量品种夏黑和低需冷量品种京蜜为试材,采取呼吸抑制剂法借助氧电极研究休眠解除过程中芽的呼吸代谢变化。【结果】不同需冷量品种休眠期间芽的呼吸速率和各呼吸途径所占比例大致相同,而且变化趋势也基本一致,但低需冷量品种京蜜呼吸速率及呼吸途径发生显著变化的时间比高需冷量品种夏黑提前20 d左右,且变化更为迅速,只是变化幅度略小于夏黑。休眠期间总呼吸速率呈单曲线变化,当休眠解除时达到顶峰。底物水平上,糖酵解-三羧酸途径所占比例在休眠解除时大幅度增加。电子传递链水平上,剩余呼吸和交替途径在休眠解除时显著增加。【结论】不同品种对低温的敏感度不同,低需冷量品种对低温刺激更为敏感。糖酵解-三羧酸途径是葡萄芽休眠解除的关键因素,剩余呼吸和交替途径的激活在葡萄芽休眠解除过程中起重要作用。     

Late Archean biospheric oxygenation and atmospheric evolution

High-resolution geochemical analyses of organic-rich shale and carbonate through the 2500 million-year-old Mount McRae Shale in the Hamersley Basin of northwestern Australia record changes in both the oxidation state of the surface ocean and the atmospheric composition. The Mount McRae record of sulfur isotopes captures the widespread and possibly permanent activation of the oxidative sulfur cycle for perhaps the first time in Earth's history. The correlation of the time-series sulfur isotope signals in northwestern Australia with equivalent strata from South Africa suggests that changes in the exogenic sulfur cycle recorded in marine sediments were global in scope and were linked to atmospheric evolution. The data suggest that oxygenation of the surface ocean preceded pervasive and persistent atmospheric oxygenation by 50 million years or more.     

沙棘林退化对林木根系和土壤抗冲性的影响

近年来,辽宁建平县亚洲最大的人工沙棘Hippophae rhamnoides林呈现大面积死亡的现象。通过标准样地法调查沙棘的死亡程度,测定与对比不同沙棘死亡率下林地的根系密度和土壤抗冲性,研究沙棘林退化对水土流失的影响。结果表明:0~30 cm范围内,直径d<1 mm的根系密度随深度增大急剧减小,72%~80%根量分布在0~20cm土层;0~30 cm范围内,随着沙棘死亡率的提高,d<1 mm根密度显著降低(P<0.05);随着深度增大,抗冲性也逐步降低,沙棘的死亡率对土壤抗冲性的影响亦达到显著水平(P<0.05),这主要是由根系密度的相应变化引起的;经曲线拟合,土壤抗冲性与d<1 mm根密度的关系可用幂函数表示。目前该区主要应通过采取有效措施降低沙棘林退化的生态影响。     

多鳞四指马鲅4个地理群体的形态差异

针对多鳞四指马鲅（Eleutheronema rhadinum）群体分布广泛,种群结构不明等突出问题,本实验分别采集了来自江苏东部海域（QD）、广东湛江附近海域（ZJ）、上海崇明附近海域（CM）、海南琼海附近海域（QH）4个地理群体共计144个样本,借助多变量形态度量学方法对4个地理群体的形态变异进行了研究,为多鳞四指马鲅不同地理群体结构研究提供资料。本文对144个样本数据校正后进行聚类分析、主成分分析和判别分析比较了4个群体间的形态差异。聚类结果表明,4个群体分为两支,CM和QD群体欧式距离最为接近,聚为一类;ZJ和QH群体聚为一类。CM、QD群体和ZJ、QH群体亲缘关系较远。主成分分析结果显示,可量数据和框架数据共计32项形态参数中,后背部和头部特征对各群体间的差异贡献率最大。运用判别分析建立4个群体的判别函数,其综合判别准确率为87.4%。分析结果显示多鳞四指马鲅4个地理群体在形态上已产生了一定程度的差异。     

Microbial reefs in the Black Sea fueled by anaerobic oxidation of methane

Massive microbial mats covering up to 4-meter-high carbonate buildups prosper at methane seeps in anoxic waters of the northwestern Black Sea shelf. Strong 13C depletions indicate an incorporation of methane carbon into carbonates, bulk biomass, and specific lipids. The mats mainly consist of densely aggregated archaea (phylogenetic ANME-1 cluster) and sulfate-reducing bacteria (Desulfosarcina/Desulfococcus group). If incubated in vitro, these mats perform anaerobic oxidation of methane coupled to sulfate reduction. Obviously, anaerobic microbial consortia can generate both carbonate precipitation and substantial biomass accumulation, which has implications for our understanding of carbon cycling during earlier periods of Earth's history.     

Isotope fractionation and atmospheric oxygen: implications for phanerozoic O(2) evolution

Models describing the evolution of the partial pressure of atmospheric oxygen over Phanerozoic time are constrained by the mass balances required between the inputs and outputs of carbon and sulfur to the oceans. This constraint has limited the applicability of proposed negative feedback mechanisms for maintaining levels of atmospheric O(2) at biologically permissable levels. Here we describe a modeling approach that incorporates O(2)-dependent carbon and sulfur isotope fractionation using data obtained from laboratory experiments on carbon-13 discrimination by vascular land plants and marine plankton. The model allows us to calculate a Phanerozoic O(2) history that agrees with independent models and with biological and physical constraints and supports the hypothesis of a high atmospheric O(2) content during the Carboniferous (300 million years ago), a time when insect gigantism was widespread.     

20th-century industrial black carbon emissions altered Arctic climate forcing

Black carbon (BC) from biomass and fossil fuel combustion alters chemical and physical properties of the atmosphere and snow albedo, yet little is known about its emission or deposition histories. Measurements of BC, vanillic acid, and non-sea-salt sulfur in ice cores indicate that sources and concentrations of BC in Greenland precipitation varied greatly since 1788 as a result of boreal forest fires and industrial activities. Beginning about 1850, industrial emissions resulted in a sevenfold increase in ice-core BC concentrations, with most change occurring in winter. BC concentrations after about 1951 were lower but increasing. At its maximum from 1906 to 1910, estimated surface climate forcing in early summer from BC in Arctic snow was about 3 watts per square meter, which is eight times the typical preindustrial forcing value.     

Plastics on the Sargasso sea surface

Plastic particles, in concentrations averaging 3500 pieces and 290 grams per square kilometer, are widespread in the western Sargasso Sea. Pieces are brittle, apparently due to the weathering of the plasticizers, and many are in a pellet shape about 0.25 to 0.5 centimeters in diameter. The particles are surfaces for the attachment of diatoms and hydroids. Increasing production of plastics, combined with present waste-disposal practices, will undoubtedly lead to increases in the concentration of these particles. Plastics could be a source of some of the polychlorinated biphenyls recently observed in oceanic organisms.     

Evolutionary trends in the geochemistry of steppe soils under long-term agricultural use

The aim of this research was to identify long-term changes in the material composition of arable and fallow lands in the agricultural district of an ancient center in the Northern Black Sea region. Geochemical features of changes in the upper mineral soil horizon of different-aged arable and fallow lands near the ancient city of Kerkinitis were studied. The multitemporal boundary between arable lands of different ages was identified, and indicators to diagnose residual signs of former agricultural loads were revealed in the material composition of agrozems using geostatistical methods. The use of such unique objects of study as soils of ancient agricultural areas is related to the potential evaluation of risks of fertility loss because of slow but practically irreversible processes of pedogenesis and the opportunity to prevent or reduce their negative manifestations in arable land.     

Global increase in quaternary explosive volcanism

The worldwide distribution of volcanic ash has been determinmined from 320 deep-sea sections drilled during the Deep Sea Drilling Project. The ash distribution in the deep-sea sections, which span the last 20 million years, indicates that there has been a much higher rate of explosive volcanism from both island arc and hot spot volcanoes during the last 2 million years. This episode, and perhaps another in the Middle Miocene cprrelates with previously reported widespread synchronism in increased volcanicity in certain oceanic islands. Increased Quaternary volcanism coincides approximately with that episode of the Cenozoic marked by major and rapidly fluctuating climatic change.