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排序方式： 共有101条查询结果，搜索用时 19 毫秒
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Serena Love 《Geoarchaeology》2012,27(2):140-156
This article provides a methodology for extracting social information through an analysis of mudbrick compositions, using a case study from Çatalhöyük, Turkey. Particle size analysis, loss on ignition, and magnetic susceptibility were used to examine variability in mudbrick recipe. The analysis revealed that neither magnetic susceptibility nor calcium carbonate were significantly altered through tempering. The results suggest that the greatest degree of compositional variability was a result of the manufacture process and not raw materials used in production. Mudbricks are products of deliberate human actions, similar to any other artifact assemblage, but have been long overlooked. Examining the technology involved with mudbrick manufacture highlights aspects of Neolithic social life through shared resources, production choices, and organization of labor. The analysis of mudbrick compositions considers how raw materials were used within and between groups of houses, represented in 1000 years of uninterrupted occupation at Çatalhöyük. 相似文献
23.
Geochemistry and quality of the groundwater from the karstic and coastal aquifer of Geropotamos River Basin at north-central Crete, Greece 总被引：2，自引：2，他引：0
Francesco Sdao Serena Parisi Despina Kalisperi Stefania Pascale Pantelis Soupios Nikos Lydakis-Simantiris Maria Kouli 《Environmental Earth Sciences》2012,67(4):1145-1153
In Geropotamos River Basin, located on the north-central part of Crete, Greece, two main factors were believed to be affecting the geochemistry of the groundwater with high salt contents: seawater intrusion and/or Miocene evaporates. To identify the origin of the high salinity in groundwater, a hydrogeochemical and isotopic study was performed. Water samples from 22 wells and 2 springs were analyzed for physico-chemical parameters, major ions analysis, as well as stable isotopes (??18O, ??D). From the present survey, in which detailed hydrogeochemical investigation was conducted, the uncertainty of the contamination sources was decreased in the northern part of Geropotamos Basin. The results complement the scenario in which seawater and the widespread human activities are the principal sources of groundwater contamination. Moreover, the results of the stable isotopes analyses (??18O and ??D) support the same hypothesis and make seawater intrusion the most probable cause for the highest salinity waters. It is indicated that saline intrusion is likely to occur along fractures in a fault zone through otherwise low-permeability phyllite?Cquartzite bedrock, which demonstrates the critical role of fracture pathways in salination problems of coastal aquifers. 相似文献
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Patricija Mozetič Cosimo Solidoro Gianpiero Cossarini Giorgio Socal Robert Precali Janja Francé Franco Bianchi Cinzia De Vittor Nenad Smodlaka Serena Fonda Umani 《Estuaries and Coasts》2010,33(2):362-375
The results of the updated and quality-checked data base of field observations on chlorophyll a (Chl a) collected in the period 1970–2007 in the Northern Adriatic Sea are presented. From the last decade, SeaWiFS satellite information
was also considered. Results demonstrate a global tendency towards Chl a reduction in the period of investigation, which is more marked in the eutrophic area under the influence of the Po River.
In the rest of the basin, which presents meso- or oligotrophic characteristics, long-term changes are more difficult to detect.
The long-term field dataset can be divided into two periods: the last decade characterized by the strong decrease observed
in the whole northern Adriatic and the earlier period with no or slight increase. The recent substantial reduction of Chl
a concentrations is confirmed all over the basin (−0.11 mg m−3 year−1) from satellite-derived information. Results are consistent with recently evidenced decrease in concentrations of phosphate
and ammonia and point to the existence of oligotrophication in the Northern Adriatic. Results indicate forcefully that the
still common perception of the Adriatic Sea as a very eutrophic basin is no longer appropriate, at least for its northern
part and in recent years. 相似文献
26.
Serena Ceola Alberto Montanari Tobias Krueger Fiona Dyer Heidi Kreibich Ida Westerberg 《水文科学杂志》2020,65(Z1):2803-2817
ABSTRACTWe explore how to address the challenges of adaptation of water resources systems under changing conditions by supporting flexible, resilient and low-regret solutions, coupled with on-going monitoring and evaluation. This will require improved understanding of the linkages between biophysical and social aspects in order to better anticipate the possible future co-evolution of water systems and society. We also present a call to enhance the dialogue and foster the actions of governments, the international scientific community, research funding agencies and additional stakeholders in order to develop effective solutions to support water resources systems adaptation. Finally, we call the scientific community to a renewed and unified effort to deliver an innovative message to stakeholders. Water science is essential to resolve the water crisis, but the effectiveness of solutions depends, inter alia, on the capability of scientists to deliver a new, coherent and technical vision for the future development of water systems.
EDITOR D. Koutsoyiannis; ASSOCIATE EDITOR not assigned 相似文献
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Metal speciation and environmental impact on sandy beaches due to El Salvador copper mine, Chile 总被引：1，自引：0，他引：1
Several coastal rocky shores in northern Chile have been affected by the discharges of copper mine tailings. The present study aims to analyze the chemical speciation of heavy metals in relation to the diversity of sessile species in the rocky intertidal benthic community on the northern Chilean coast, which is influenced by the presence of copper mine tailings. In particular, the chemical forms of Cd, Cu, Fe, Mn, Ni, Pb and Zn in beach sediment samples collected in the area influenced by El Salvador mine tailings were studied using a sequential chemical extraction method. In general, all the elements present a maximum concentration in the area near the actual discharge point (Caleta Palito). With regard to Cu and Mn, the concentrations range between 7.2-985 and 746-22,739 microg/g respectively, being lower than background levels only in the control site of Caleta Zenteno. Moreover, the correlation coefficients highlight that Fe, Mn and Ni correlate significantly and positively in the studied area, showing a possible common, natural origin, whilst Cu shows a negative correlation with Fe, Mn and Ni. It could be possible that Cu has an anthropogenic origin, coming from mining activity in the area. Cd, Fe, Mn, Ni, Pb and Zn are mostly associated with the residual phase, whilst Cu presents a different speciation pattern, as resulted from selective extractions. In fact, Cu is highly associated with organic and exchangeable phases in contaminated localities, whilst it is mainly bound to the residual phase in control sites. Moreover, our results, compared to local biological diversity, showed that those sites characterized by the highest metal concentrations in bioavailable phase had the lowest biodiversity. 相似文献
30.
Serena Viti Hugh R. A. Jones Pierre Maxted Jonathan Tennyson 《Monthly notices of the Royal Astronomical Society》2002,329(2):290-300
We compare observations of the eclipsing binary system CM Draconis (hereafter CM Dra) with synthetic spectra computed using the stellar atmosphere code phoenix . High-resolution infrared spectroscopic observations of six 0.05-μm-wide regions between 1.51 and 2.45 μm, combined with previous work, particularly CM Dra's accurately known surface gravity, enable us to estimate its metallicity using detailed spectral synthesis. We find significant discrepancies between the observed and synthetic spectra throughout most of the region emphasizing the need for higher quality atomic data in the infrared. Nevertheless, the CO bands beyond 2.3 μm seem to be well modelled and metal-sensitive, and thus high-resolution spectra should be a most powerful diagnostic tool for spectroscopic analyses for M dwarfs and brown dwarfs. The CO bands indicate a metallicity of around −1 dex for CM Dra. This result is supported by observations of two M dwarfs of similar spectral type, GJ 699 (Barnard's star) and GJ 725B. This result supports inferences from previous infrared work, although it does not agree with standard evolutionary models or optical analyses, which both suggest an abundance for CM Dra close to that of the Sun. 相似文献