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971.
972.
J. N. Proust J. F. Deconinck J. R. Geyssant J. P. Herbin J. P. Vidier 《Geologische Rundschau》1995,84(2):255-271
An interdisciplinary approach based on high-resolution physical stratigraphy, biostratigraphy, organic matter analysis and clay mineralogy has been applied to the mixed siliciclastic/carbonate Kimmeridgian/Tithonian deposits of the Boulonnais (north-western France). These rocks are the age-equivalents of some of the offshore marine source rocks of the North Sea and were deposited in an overall storm-dominated homoclinal ramp setting which may represent one of the most shore-proximal sediments of this age cropping out in north-western Europe. Comparison with data from the Yorkshire, Dorset, Lorraine and Aquitaine areas allows the discrimination of three major transgressive-regressive sediment packages with disconformities of interregional extent: (1) from the Baylei Zone to top Eudoxus Zone; (2) from the Autissiodorensis Zone to base Scitulus Zone; (3) from the upper Scitulus Zone to the Pectinatus Zone. The lower two regionally correlative disconformities correspond to the sequence boundaries at the top of the Eudoxus Zone and the top of the Autissiodorensis Zone, formed by high-frequency relative sea-level variations during the periods of maximum transgression of the platform. The latter disconformity (the P1 nodule bed) reflects a major tectonically induced reorganization of the north-west European intrashelf sedimentary basin, characterized by a shift in both the location of the main depocentre and the sources of sediment production. 相似文献
973.
Alshehri Ali S. El-Kott Attalla F. El-Kenawy Ayman E. Zaki Mohamed Samir A. Morsy Kareem Ghanem Reham A. Salem Eman T. Ebealy Eman R. Khalifa Heba S. Altyar Ahmed E. AlGwaiz Hussah I. M. Ibrahim Essam H. Mahmoud Mohammed S. Dallak Mohammad A. Abd-Ella Eman M. 《Environmental science and pollution research international》2022,29(38):57591-57602
Environmental Science and Pollution Research - This study evaluated the nephroprotective effect of kaempferol against cadmium chloride (CdCl2) -induced nephropathy in rats. It also investigated if... 相似文献
974.
Sitharthan R. M Rajesh 《Environmental science and pollution research international》2022,29(14):19919-19919
Environmental Science and Pollution Research - 相似文献
975.
Carl Folke Stephen Polasky Johan Rockstrm Victor Galaz Frances Westley Michle Lamont Marten Scheffer Henrik
sterblom Stephen R. Carpenter F. Stuart Chapin III Karen C. Seto Elke U. Weber Beatrice I. Crona Gretchen C. Daily Partha Dasgupta Owen Gaffney Line J. Gordon Holger Hoff Simon A. Levin Jane Lubchenco Will Steffen Brian H. Walker 《Ambio》2021,50(4):834
The COVID-19 pandemic has exposed an interconnected and tightly coupled globalized world in rapid change. This article sets the scientific stage for understanding and responding to such change for global sustainability and resilient societies. We provide a systemic overview of the current situation where people and nature are dynamically intertwined and embedded in the biosphere, placing shocks and extreme events as part of this dynamic; humanity has become the major force in shaping the future of the Earth system as a whole; and the scale and pace of the human dimension have caused climate change, rapid loss of biodiversity, growing inequalities, and loss of resilience to deal with uncertainty and surprise. Taken together, human actions are challenging the biosphere foundation for a prosperous development of civilizations. The Anthropocene reality—of rising system-wide turbulence—calls for transformative change towards sustainable futures. Emerging technologies, social innovations, broader shifts in cultural repertoires, as well as a diverse portfolio of active stewardship of human actions in support of a resilient biosphere are highlighted as essential parts of such transformations. 相似文献
976.
The distribution of arsenic in the stems of fruit trees grown in soils exposed to arsenical pesticides has been studied using neutron activation analysis. The results show arsenic to be confined mainly to heartwood near the pith and active xylem tissue in the most recent annual growth rings. These results suggest that dendroanalysis for arsenic in fruit trees will not yield a reliable chronology of arsenic exposure. 相似文献
977.
Soil organic matter mobilization by root exudates 总被引:15,自引:0,他引:15
In order to study the different soil organic matter mobilisation by agrarian (Zea mais: cultivars Paolo and Sandek) and forest (Picea abies Karst. and Pinus sylvestris L.) root exudates, three different soils (Dystric Spodic Cambisol--S1, Haplic Luvisol--S2 and Calcaric Cambisol--S3) have been considered. Treating the soils with water (control) or plant root exudates, soil organic matter extracts were obtained. The extracts were characterised by hormone-like activities and gas chromatographic/mass spectrometric (GC/MS) measurements. Water extract and plant root exudates exhibited no hormone-like activity, while the other soil-extracts were endowed with a different hormone-like behaviour. GC/MS data indicated that in the acid soils (S1) Sandek and Picea abies exudates showed a greater ability in extracting organic acid isomers (Cl4COOH, Cl5COOH and Cl7COOH), while in neutral soils (S3) all the exudates were active in separating organic acids. In intermediate conditions (S2), Picea abies and Pinus sylvestris exudates liberated C15COOH isomers, Paolo C11COOH isomers, while Sandek was not effective. The different role of plant root exudates in mobilising bio-molecules from the bulk of the soil is proposed. 相似文献
978.
Holt MS Fox K Griessbach E Johnsen S Kinnunen J Lecloux A Murray-Smith R Peterson DR Schröder R Silvani M ten Berge WF Toy RJ Feijtel TC 《Chemosphere》2000,41(11):1799-1808
Monitoring and laboratory data play integral roles alongside fate and exposure models in comprehensive risk assessments. The principle in the European Union Technical Guidance Documents for risk assessment is that measured data may take precedence over model results but only after they are judged to be of adequate reliability and to be representative of the particular environmental compartments to which they are applied. In practice, laboratory and field data are used to provide parameters for the models, while monitoring data are used to validate the models' predictions. Thus, comprehensive risk assessments require the integration of laboratory and monitoring data with the model predictions. However, this interplay is often overlooked. Discrepancies between the results of models and monitoring should be investigated in terms of the representativeness of both. Certainly, in the context of the EU risk assessment of existing chemicals, the specific requirements for monitoring data have not been adequately addressed. The resources required for environmental monitoring, both in terms of manpower and equipment, can be very significant. The design of monitoring programmes to optimise the use of resources and the use of models as a cost-effective alternative are increasing in importance. Generic considerations and criteria for the design of new monitoring programmes to generate representative quality data for the aquatic compartment are outlined and the criteria for the use of existing data are discussed. In particular, there is a need to improve the accessibility to data sets, to standardise the data sets, to promote communication and harmonisation of programmes and to incorporate the flexibility to change monitoring protocols to amend the chemicals under investigation in line with changing needs and priorities. 相似文献
979.
Fu L Hao J Hertel O Berkowicz R 《Journal of the Air & Waste Management Association (1995)》2000,50(12):2060-2066
It is important to develop a general model to accurately simulate the air pollution in urban street areas. In this paper, the Operational Street Pollution Model (OSPM) initially developed in Denmark is tested with measured data from a relatively wide and open street in Beijing. Major factors influencing the dispersion, such as emission factors, stationary source emissions, and solar radiation, are analyzed. Results show that the model can reflect the basic dispersion pattern in the street but gives systematically higher concentrations. After modifications to estimate street-level wind speed in the model, performance is obviously improved. 相似文献
980.
MacLean HL Lave LB Lankey R Joshi S 《Journal of the Air & Waste Management Association (1995)》2000,50(10):1769-1779
We examine the life cycles of gasoline, diesel, compressed natural gas (CNG), and ethanol (C2H5OH)-fueled internal combustion engine (ICE) automobiles. Port and direct injection and spark and compression ignition engines are examined. We investigate diesel fuel from both petroleum and biosources as well as C2H5OH from corn, herbaceous bio-mass, and woody biomass. The baseline vehicle is a gasoline-fueled 1998 Ford Taurus. We optimize the other fuel/powertrain combinations for each specific fuel as a part of making the vehicles comparable to the baseline in terms of range, emissions level, and vehicle lifetime. Life-cycle calculations are done using the economic input-output life-cycle analysis (EIO-LCA) software; fuel cycles and vehicle end-of-life stages are based on published model results. We find that recent advances in gasoline vehicles, the low petroleum price, and the extensive gasoline infrastructure make it difficult for any alternative fuel to become commercially viable. The most attractive alternative fuel is compressed natural gas because it is less expensive than gasoline, has lower regulated pollutant and toxics emissions, produces less greenhouse gas (GHG) emissions, and is available in North America in large quantities. However, the bulk and weight of gas storage cylinders required for the vehicle to attain a range comparable to that of gasoline vehicles necessitates a redesign of the engine and chassis. Additional natural gas transportation and distribution infrastructure is required for large-scale use of natural gas for transportation. Diesel engines are extremely attractive in terms of energy efficiency, but expert judgment is divided on whether these engines will be able to meet strict emissions standards, even with reformulated fuel. The attractiveness of direct injection engines depends on their being able to meet strict emissions standards without losing their greater efficiency. Biofuels offer lower GHG emissions, are sustainable, and reduce the demand for imported fuels. Fuels from food sources, such as biodiesel from soybeans and C2H5OH from corn, can be attractive only if the co-products are in high demand and if the fuel production does not diminish the food supply. C2H5OH from herbaceous or woody biomass could replace the gasoline burned in the light-duty fleet while supplying electricity as a co-product. While it costs more than gasoline, bioethanol would be attractive if the price of gasoline doubled, if significant reductions in GHG emissions were required, or if fuel economy regulations for gasoline vehicles were tightened. 相似文献