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51.
Pharmaceuticals and Other Organic Waste Water Contaminants Within a Leachate Plume Downgradient of a Municipal Landfill 总被引:1,自引:0,他引:1
Kimberlee K. Barnes Scott C. Christenson Dana W. Kolpin Michael J. Focazio Edward T. Furlong Steven D. Zaugg Michael T. Meyer Larry B. Barber 《Ground Water Monitoring & Remediation》2004,24(2):119-126
Ground water samples collected from the Norman Landfill research site in central Oklahoma were analyzed as part of the U.S. Geological Survey (USGS) Toxic Substances Hydrology Program's national reconnaissance of pharmaceuticals and other organic waste water contaminants (OWCs) in ground water. Five sites, four of which are located downgradient of the landfill, were sampled in 2000 and analyzed for 76 OWCs using four research methods developed by the USGS. OWCs were detected in water samples from all of the sites sampled, with 22 of the 76 OWCs being detected at least once. Cholesterol (a plant and animal steroid), was detected at all five sites and was the only compound detected in a well upgradient of the landfill. N,N-diethyltoluamide (DEBT used in insect repellent) and tri(2-chloroethyl) phosphate (fire-retardant) were detected in water samples from all four sites located within the landfill-derived leachate plume. The sites closest to the landfill had more detections and greater concentrations of each of the detected compounds than sites located farther away. Detection of multiple OWCs occurred in the four sites located within the leachate plume, with a minimum of four and a maximum of 17 OWCs detected. Because the landfill was established in the 1920s and closed in 1985, many compounds detected in the leachate plume were likely disposed of decades ago. These results indicate the potential for long-term persistence and transport of some OWCs in ground water. 相似文献
52.
Quantitative plant macrofossil and colorimetric humification analyses have been used to reconstruct proxy-climate from two paired ombrotrophic bogs in northern England (Coom Rigg Moss and Felecia Moss). Detrended correspondence analysis was used to transform the raw floral data into indices of mire surface wetness. The chronology of each peat profile was determined by radiocarbon assay, supported by pollen correlations. Palaeoclimatic reconstructions have been made by linking documented historical changes in climate, and other proxy-climate records, to those inferred from the sites investigated in the study region. Both sites contain a sensitive palaeoclimatic record, as ten periods of increased effective precipitation have been detected between ca. cal. ad 1770–1800, ad 1400–1470, ad 1110–1260, ad 920–1060, ad 550–670, ad 210–360, 30 bc to ad 80, 180–130 bc, 590–520 bc and 760–710 bc. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
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T-C Livingstone JM Harris AT Lombard AJ Smit DS Schoeman 《African Journal of Marine Science》2018,40(1):51-65
Marine bioregional planning requires a meaningful classification and spatial delineation of the ocean environment using biological and physical characteristics. The relative inaccessibility of much of the ocean and the paucity of directly measured data spanning entire planning regions mean that surrogate data, such as satellite imagery, are frequently used to develop spatial classifications. However, due to a lack of appropriate biological data, these classifications often rely on abiotic variables, which act as surrogates for biodiversity. The aim of this study was to produce a fine-scale bioregional classification, using multivariate clustering, for the inshore and offshore marine environment off the east coast of South Africa, adjacent to the province of KwaZulu-Natal and out to the boundary of the exclusive economic zone (EEZ), 200 nautical miles offshore. We used remotely sensed data of sea surface temperature, chlorophyll a and turbidity, together with interpolated bathymetry and continental-slope data, as well as additional inshore data on sediments, seabed oxygen and bottom temperature. A multivariate k-means analysis was used to produce a fine-scale marine bioregionalisation, with three bioregions subdivided into 12 biozones. The offshore classification was primarily a pelagic bioregionalisation, whereas the inshore classification (on the continental shelf) was a coupled benthopelagic bioregionalisation, owing to the availability of benthic data for this area. The resulting classification was used as a base layer for a systematic conservation plan developed for the province, and provided the methods for subsequent planning conducted for the entire South African EEZ. Validation of the classification is currently being conducted in marine research programmes that are sampling benthic biota and habitats in a sampling design stratified according to the biozones delineated in this study. 相似文献
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Two new peat‐based climate records from Ireland covering the late Holocene are presented. The sequences are dated by a strong chronological framework formed by AMS radiocarbon dates and SCPs. Three proxy indicators (testate amoebae, macrofossils and humification) have been determined allowing the limitations and strengths of each to be identified and utilised to provide a bog surface wetness (BSW) record for both sites. Age–depth models take into account the potential for accumulation rates to vary with bog vegetation. The records from each site have been used to derive a combined BSW record that displays changes to a wetter/cooler climate from ca. AD 30 (1920 BP), ca. AD 310 (1640 BP), ca. AD 805 (1145 BP), ca. AD 1040 (910 BP) and ca. AD 1300 (650 BP). Changes follow closely those identified in a northern Britain composite BSW record and largely correspond with lake‐level data in central France suggesting the main changes in water balance were coherent over a large region. Correspondence with increases in IRD and slower Iceland‐Scotland Overflow Water (ISOW) suggests that these changes were related to oceanic forcing influencing the track of dominant westerly air flow over Ireland. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
56.
Sea ice dynamic and thermodynamic processes are important and highly variable elements of the marginal ice zone (MIZ). This study examines the detection and classification of statistically separable sea ice classes in the MIZ through a range of temporal and spatial scales. A helicopter‐based laser system was used to obtain large‐scale and a ship‐based laser profiler to identify small‐scale roughness types, respectively. The analysis of variance of surface height data from helicopter‐ and ship‐based laser systems, active microwave (AMW) C‐band backscattering data and passive microwave (PMW) (37 and 89 GHz) brightness temperature data reveal different classes that statistically differ from one another. We found significant statistical difference in variances in AMW data with six classes that differ in VV polarization, three classes in VH polarization, and five classes in HH polarization in the MIZ (e.g. snow‐covered first‐year ice, ice rubble, pancake ice, frost flowers, melt pond, flooded ice, and ice edge) of southeastern Beaufort Sea. The PMW emission was not as effective at discrimination, yielding only one statistically separable class. The results can potentially be extended to satellite‐based investigations of the MIZ at regional scales. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
57.
M. C. Ghiglione J. Likerman V. Barberón L. Beatriz Giambiagi B. Aguirre‐Urreta F. Suarez 《Basin Research》2014,26(6):726-745
We present field and seismic evidence for the existence of Coniacian–Campanian syntectonic angular unconformities within basal foreland basin sequences of the Austral or Magallanes Basin, with implications for the understanding of deformation and sedimentation in the southern Patagonian Andes. The studied sequences belong to the mainly turbiditic Upper Cretaceous Cerro Toro Formation that includes a world‐class example of conglomerate‐filled deep‐water channel bodies deposited in an axial foredeep depocentre. We present multiple evidence of syntectonic deposition showing that the present internal domain of the fold‐thrust belt was an active Coniacian–Campanian wedge‐top depozone where deposition of turbidites and conglomerate channels of Cerro Toro took place. Cretaceous synsedimentary deformation was dominated by positive inversion of Jurassic extensional structures that produced elongated axial submarine trenches separated by structural highs controlling the development and distribution of axial channels. The position of Coniacian‐Campanian unconformities indicates a ca. 50–80 km advance of the orogenic front throughout the internal domain, implying that Late Cretaceous deformation was more significant in terms of widening the orogenic wedge than all subsequent Andean deformation stages. This south Patagonian orogenic event can be related to compressional stresses generated by the combination of both the collision of the western margin of Rocas Verdes Basin during its closure, and Atlantic ridge push forces due to its accelerated opening, during a global‐scale plate reorganization event. 相似文献
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R. J. Barber J. Tennyson G. J. Harris R. N. Tolchenov 《Monthly notices of the Royal Astronomical Society》2006,368(3):1087-1094
A computed list of H2 16 O infrared transition frequencies and intensities is presented. The list, BT2, was produced using a discrete variable representation two-step approach for solving the rotation–vibration nuclear motions. It is the most complete water line list in existence, comprising over 500 million transitions (65 per cent more than any other list) and it is also the most accurate (over 90 per cent of all known experimental energy levels are within 0.3 cm−1 of the BT2 values). Its accuracy has been confirmed by extensive testing against astronomical and laboratory data.
The line list has been used to identify individual water lines in a variety of objects including comets, sunspots, a brown dwarf and the nova-like object V838 Mon. Comparison of the observed intensities with those generated by BT2 enables water abundances and temperatures to be derived for these objects. The line list can also be used to provide an opacity for models of the atmospheres of M dwarf stars and assign previously unknown water lines in laboratory spectra. 相似文献
The line list has been used to identify individual water lines in a variety of objects including comets, sunspots, a brown dwarf and the nova-like object V838 Mon. Comparison of the observed intensities with those generated by BT2 enables water abundances and temperatures to be derived for these objects. The line list can also be used to provide an opacity for models of the atmospheres of M dwarf stars and assign previously unknown water lines in laboratory spectra. 相似文献