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991.
The paleoclimatic record of Juréia Paleolagoon, coastal southeastern Brazil, includes cyclic and gradual changes with different intensities and frequencies through geological time, and it is controlled by astronomical, geophysical, and geological phenomena. These variations are not due to one single cause, but they result from the interaction of several factors, which act at different temporal and spatial scales. Here, we describe paleoenvironmental evidence regarding climatic and sea level changes from the last 9400 cal yr BP at the Juréia Paleolagoon — one of the main groups of protected South Atlantic ecosystems. Geochemical evidences were used to identify anomalies from multi-proxy analyses of a paleolagoon sediment core. The anomalies of centennial scale were correlated to climate and transgression–regression cycles from the Holocene period. Decadal scale anomalous oscillations in the Quaternary paleolagoon sediments occur between 9400 and 7500 cal yr BP, correlated with long- and short-term natural events, which generated high sedimentation rates, mainly between 8385 and 8375 cal yr BP (10 cm/yr). Our results suggest that a modern-day short-duration North Atlantic climatic event, such as the 8.2 ka event, could affect the environmental equilibrium in South America and intensify the South American Summer Monsoon.  相似文献   
992.
This synthesis integrates recently acquired archaeological and geological data with earlier documented observations to shed light on the subsidence of ancient Greek coastal facilities in southern Italy. These are now positioned between former shorelines and inner shelf sectors at five Calabrian margin localities. Submergence of coastal to inner shelf facilities has resulted in part from sea‐level rise by about 2 m associated with glacio‐hydro‐isostatic factors since archaic to classic Greek time. This phenomenon alone, however, does not explain the wide variation of measured subsidence rates from site‐to‐site. The marked lowering of coastal site substrates by seismo‐tectonic activity (including extensional fault motion), stratal readjustments at depth, and compaction of underlying sediment sequences is significant. Four of the subsided facilities are positioned near emerged Calabrian areas where prevailing Holocene average annual land uplift rates range to ˜1.0 mm/yr; at the fifth, near Hipponion, terrains have risen by nearly 2 mm/yr. In marked contrast, submerged and/or buried structures record the following late Holocene long‐term average rates of coastal margin subsidence: Sybaris‐Thuri on the Taranto Gulf margin (˜0.5–1.0 mm/yr); Hipponion‐Vibo Valentia along the Tyrrhenian coast (˜0.8 to ˜3.2 mm/yr); and Locri‐Epizefiri, Kaulonia, and Capo Colonna on Calabria's Ionian margin (˜1.6, ˜1.6–2.4, and ˜4.0 mm/yr, respectively). © 2012 Wiley Periodicals, Inc.  相似文献   
993.
994.
There is a significant relationship between ambient temperature and mortality. In healthy individuals with no underlying co-morbid conditions, there is an efficient heat regulation system which enables the body to effectively handle thermal stress. However, in vulnerable groups, especially in elderly over the age of 65 years, infants and individuals with co-morbid cardiovascular and/or respiratory conditions, there is a deficiency in thermoregulation. When temperatures exceed a certain limit, being cold winter spells or heat waves, there is an increase in the number of deaths. In particular, it has been shown that at temperatures above 27 °C, the daily mortality rate increases more rapidly per degree rise compared to when it drops below 27 °C.This is especially of relevance with the current emergency of global warming. Besides the direct effect of temperature rises on human health, global warming will have a negative impact on primary producers and livestock, leading to malnutrition, which will in turn lead to a myriad of health related issues. This is further exacerbated by environmental pollution.Public health measures that countries should follow should include not only health-related information strategies aiming to reduce the exposure to heat for vulnerable individuals and the community, but improved urban planning and reduction in energy consumption, among many others. This will reduce the carbon footprint and help avert global warming, thus reducing mortality.  相似文献   
995.
Through their consumption behavior, households are responsible for 72% of global greenhouse gas emissions. Thus, they are key actors in reaching the 1.5 °C goal under the Paris Agreement. However, the possible contribution and position of households in climate policies is neither well understood, nor do households receive sufficiently high priority in current climate policy strategies. This paper investigates how behavioral change can achieve a substantial reduction in greenhouse gas emissions in European high-income countries. It uses theoretical thinking and some core results from the HOPE research project, which investigated household preferences for reducing emissions in four European cities in France, Germany, Norway and Sweden. The paper makes five major points: First, car and plane mobility, meat and dairy consumption, as well as heating are the most dominant components of household footprints. Second, household living situations (demographics, size of home) greatly influence the household potential to reduce their footprint, even more than country or city location. Third, household decisions can be sequential and temporally dynamic, shifting through different phases such as childhood, adulthood, and illness. Fourth, short term voluntary efforts will not be sufficient by themselves to reach the drastic reductions needed to achieve the 1.5 °C goal; instead, households need a regulatory framework supporting their behavioral changes. Fifth, there is a mismatch between the roles and responsibilities conveyed by current climate policies and household perceptions of responsibility. We then conclude with further recommendations for research and policy.  相似文献   
996.
During the Variscan orogeny in Central Europe, partial melting in the lower continental crust formed granitic magmas, which intruded into the upper crust and left compounds of Ca (plus Eu2+), Mg, etc. in the lower crust. From the late Paleozoic decomposition of the tonalitic upper crust, sedimentary graywackes were produced reflecting the composition of this crust. The repeated reworking of the sedimentary cover caused the formation of sands. Sandstones as their products of consolidation contain increasing fractions of quartz and decreasing feldspar from Carboniferous and Triassic to Cretaceous age. A distinct negative Eu anomaly characterizes the majority of these rocks. The latter is imprinted by the Variscan magmatism. Quartz as used for numerous Medieval wood ash glasses is marked for its Central European origin by a distinct negative Eu anomaly in contrast to many soda glasses produced outside Germany mostly with a small or none Eu anomaly.  相似文献   
997.
Index species useful for correlations with the International Stratigraphical Column are rare or absent in the Pennsylvanian–Permian strata of the Paraná Basin in Brazil, preventing accuracy in geochronologic assignments. Besides, absolute datings are very scarce in comparison with other Gondwana basins. This paper presents palynological data from an outcrop on the surroundings of the Candiota coal mine, southmost Brazil, from several levels of the Rio Bonito and Palermo formations. The presence of certain index species of spore–pollen allowed the recognition of two Permian palynozones: the Vittatina costabilis and the Lueckisporites virkkiae zones. Furthermore, U–Pb in zircons from a volcaniclastic level interbedded in the coal strata of the former unit was analyzed through LA-MC-ICP-MS method, providing a new absolute age dating of 281.4 ± 3.4 Ma (Cisuralian, Early Permian). This dating is assumed as the oldest occurrence of the L. virkkiae Zone in Paraná Basin, which contains index species that are widespread in other Gondwana basins. A well distributed surface boundary occurs in this section also, allowing local and regional correlations. These new biostratigraphical and geochronological data are integrated, in order to offer a deep analysis on the stratigraphical significance for correlations across the Occidental Gondwana.  相似文献   
998.
Pharmaceuticals as indictors of sewage-influenced groundwater   总被引:1,自引:0,他引:1  
A set of human pharmaceuticals enables identification of groundwater that is influenced by sewage and provides information on the time of recharge. As the consumption rates of the investigated pharmaceuticals have changed over time, so too has the composition of the sewage. At the study area, south of Berlin (Germany), irrigation was performed as a method of wastewater clean-up at sewage irrigation farms until the early 1990s. Today, treated wastewater is discharged into the surface-water-stream Nuthegraben. Groundwater and surface-water samples were analyzed for the pharmaceutical substances clofibric acid, bezafibrate, diclofenac, carbamazepine and primidone, the main ions and organic carbon. The pharmaceutical substances were detected at concentrations up to microgram-per-liter level in groundwater and surface-water samples from the Nuthegraben Lowland area and from the former irrigation farms. Concentrations detected in groundwater are generally much lower than in surface water and there is significant variation in the distribution of pharmaceutical concentrations in groundwater. Groundwater influenced by the irrigation of sewage water shows higher primidone and clofibric-acid concentrations. Groundwater influenced by recent discharge of treated sewage water into the surface water shows high carbamazepine concentrations while concentrations of primidone and clofibric acid are low.  相似文献   
999.
1000.
Dating the magmatic events in the Montagne Noire gneiss dome is a key point to arbitrate between the different interpretations of the Late Carboniferous–Early Permian tectonics in this southern part of the Variscan belt. The Saint-Eutrope orthogneiss crops out along the northern flank of the dome. We show that the protolith of this orthogneiss is an Ordovician granite dated at 455 ± 2 Ma (LA-ICP-MS U-Pb dating on zircon). This age is identical to that previously obtained on the augen orthogneiss of the southern flank, strongly suggesting that both orthogneiss occurrences have the same Ordovician protolith. The Saint-Eutrope orthogneiss experienced intense shearing along the Espinouse extensional detachment at ca. 295 Ma (LA-ICP-MS U-Pb-Th on monazite), an age close to that determined previously on mica by the 39Ar-40Ar method and contemporaneous with the emplacement age of the syntectonic Montalet granite farther to the west. This normal sense shearing reworked previous fabrics related to Variscan thrusting that can be still observed in the augen orthogneiss of the southern flank, and is responsible for the spectacular “C/S-like” pattern of the Saint-Eutrope orthogneiss. This work also shows that care is needed when dealing with C/S-type structures, since they can develop not only in syntectonic intrusions, but also in orthogneisses affected by an intense secondary deformation, at decreasing temperature.  相似文献   
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