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431.
Mapping vulnerability to multiple stressors: climate change and globalization in India 总被引:7,自引:0,他引:7
Karen OBrien Robin Leichenko Ulka Kelkar Henry Venema Guro Aandahl Heather Tompkins Akram Javed Suruchi Bhadwal Stephan Barg Lynn Nygaard Jennifer West 《Global Environmental Change》2004,14(4):627
There is growing recognition in the human dimensions research community that climate change impact studies must take into account the effects of other ongoing global changes. Yet there has been no systematic methodology to study climate change vulnerability in the context of multiple stressors. Using the example of Indian agriculture, this paper presents a methodology for investigating regional vulnerability to climate change in combination with other global stressors. This method, which relies on both vulnerability mapping and local-level case studies, may be used to assess differential vulnerability for any particular sector within a nation or region, and it can serve as a basis for targeting policy interventions. 相似文献
432.
Laurence G Miller Karen L Warner Ronald S Oremland Stefan Radajewski 《Geochimica et cosmochimica acta》2004,68(15):3271-3283
Bacteria in soil microcosm experiments oxidized elevated levels of methyl chloride (MeCl) and methyl bromide (MeBr), the former compound more rapidly than the latter. MeBr was also removed by chemical reactions while MeCl was not. Chemical degradation dominated the early removal of MeBr and accounted for more than half of its total loss. Fractionation of stable carbon isotopes during chemical degradation of MeBr resulted in a kinetic isotope effect (KIE) of 59 ± 7‰. Soil bacterial oxidation dominated the later removal of MeBr and MeCl and was characterized by different KIEs for each compound. The KIE for MeBr oxidation was 69 ± 9‰ and the KIE for MeCl oxidation was 49 ± 3‰. Stable isotope probing revealed that different populations of soil bacteria assimilated added 13C-labeled MeBr and MeCl. The identity of the active MeBr and MeCl degrading bacteria in soil was determined by analysis of 16S rRNA gene sequences amplified from 13C-DNA fractions, which identified a number of sequences from organisms not previously thought to be involved in methyl halide degradation. These included Burkholderia, the major clone type in the 13C-MeBr fraction, and Rhodobacter, Lysobacter and Nocardioides the major clone types in the 13C-MeCl fraction. None of the 16S rRNA gene sequences for methyl halide oxidizing bacteria currently in culture (including Aminobacter strain IMB-1 isolated from fumigated soil) were identified. Functional gene clone types closely related to Aminobacter spp. were identified in libraries containing the sequences for the cmuA gene, which codes for the enzyme known to catalyze the initial step in the oxidation of MeBr and MeCl. The cmuA gene was limited to members of the alpha-Proteobacteria whereas the greater diversity demonstrated by the 16S rRNA gene may indicate that other enzymes catalyze methyl halide oxidation in different groups of bacteria. 相似文献
433.
Jochen Vogl Yong‐Hyeon Yim Kyoung‐Seok Lee Heidi Goenaga‐Infante Dmitriy Malinovskiy Sarah Hill Tongxiang Ren Jun Wang Robert D. Vocke Karen E. Murphy Naoko Nonose Olaf Rienitz Janine Noordmann 《Geostandards and Geoanalytical Research》2019,43(1):23-37
Lead isotope amount ratios are commonly used in diverse fields such as archaeometry, geochemistry and forensic science. Currently, five reference materials with certified lead isotope amount ratios are available, namely NIST SRM 981, 982 and 983, GBW‐04442 and NMIJ 3681‐a. Only NIST SRM 981 and NMIJ 3681‐a have approximately natural isotopic compositions, and NIST SRM 981 is predominantly used for correcting mass discrimination/mass fractionation in the applied mass spectrometric procedures. Consequently, there is no other certified reference material available to be used for validation and/or quality control of the analytical procedures applied to lead isotope amount ratio measurements. To fill this gap, two new reference materials have been produced and certified for their lead isotope amount ratios. For both certified reference materials, complete uncertainty budgets have been calculated and SI traceability has been established. This provides the users with independent means for validating and verifying their analytical procedures and for conducting quality control measures. ERM‐EB400 is a bronze material with a nominal lead mass fraction of 45 mg kg?1 and certified lead isotope amount ratios of n(206Pb)/n(204Pb) = 18.072(17) mol mol?1, n(207Pb)/n(204Pb) = 15.578(18) mol mol?1 and n(208Pb)/n(204Pb) = 38.075(46) mol mol?1 with the associated expanded uncertainties (k = 2) given in brackets. ERM‐AE142 is a high‐purity solution of lead in 2% nitric acid with a nominal mass fraction of 100 mg kg?1 and certified Pb isotope amount ratios of n(206Pb)/n(204Pb) = 21.114(17) mol mol?1, n(207Pb)/n(204Pb) = 15.944(17) mol mol?1 and n(208Pb)/n(204Pb) = 39.850(44) mol mol?1 with the associated expanded uncertainties (k = 2) given in brackets. Both materials are specifically designed to fall within the natural lead isotopic variation and to assist users with the validation and verification of their analytical procedures. Note that while one of these reference materials requires the chemical separation of Pb from its matrix (ERM‐EB400), the other does not (ERM‐AE142). As additional information, δ208/206PbNIST SRM981 values are provided for both materials. For ERM‐AE142, a delta value of δ208/206PbNIST SRM981 = ?28.21(30)‰ was obtained, and for ERM‐EB400, a delta value of δ208/206PbNIST SRM981= ?129.47(38)‰ was obtained, with the associated expanded uncertainties (k = 2) given in brackets. 相似文献
434.
Ruoppolo V Vanstreels RE Woehler EJ Heredia SA Adornes AC da Silva-Filho RP Matus R Poleschi C Griot K Kolesnikovas CK Serafini P 《Marine pollution bulletin》2012,64(7):1309-1317
Oil pollution is a significant conservation concern. We examined data from six institutions along the coast of South America: Emergency Relief Team of the International Fund for Animal Welfare, Fundación Mundo Marino, Centro de Recupera??o de Animais Marinhos, Natura Patagonia, Associa??o R3 Animal, and Mar del Plata Aquarium and data from resightings in Argentina, Brazil, Chile and Falkland/Malvinas Islands. From 2000 to 2010, 2183 oiled Magellanic penguins were rehabilitated as part of the routine activities of these institutions or during emergency responses to eight oil spills in which they were involved; all rehabilitated penguins were flipper banded and released. Since their release, 41 penguins were resighted until 31 December 2011. The results demonstrate that, when combined with other prevention strategies, the rehabilitation of Magellanic penguins is a strategy that contributes to the mitigation of adverse effects of oil spills and chronic pollution to the species. 相似文献
435.
436.
The Recreation Opportunity Spectrum (ROS) has been used internationally as a tool to guide recreation planning. The spectrum as a map has primarily been generated manually and through digitisation by analysts with an in-depth knowledge of the region of interest. This paper seeks to outline an alternative method that is objective and repeatable to create a ROS map for New Zealand, using data from a variety of sources and manipulated with spatial tools available in a geographic information system. The result is a map that is consistent on a national scale, and a method that is repeatable. The model can be used to develop scenario modelling, change detection, and help guide management decisions. 相似文献
437.
A Practical Approach to the Design, Monitoring, and Optimization of In Situ MTBE Aerobic Biobarriers
Paul C. Johnson Cristin L. Bruce Karen D. Miller 《Ground Water Monitoring & Remediation》2010,30(1):58-66
A paradigm for the design, monitoring, and optimization of in situ methyl tert -butyl ether (MTBE) aerobic biobarriers is presented. In this technology, an oxygen-rich biologically reactive treatment zone (the "biobarrier") is established in situ and downgradient of the source of dissolved MTBE contamination in groundwater, typically gasoline-impacted soils resulting from leaks and spills at service station sites or other fuel storage and distribution facilities. The system is designed so that groundwater containing dissolved MTBE flows to, and through, the biobarrier treatment zone, ideally under natural gradient conditions so that no pumping is necessary. As the groundwater passes through the biobarrier, the MTBE is converted by microorganisms to innocuous by-products. The system also reduces concentrations of other aerobically degradable chemicals dissolved in the groundwater, such as benzene, toluene, xylenes, and tert -butyl alcohol. This design paradigm is based on experience gained while designing, monitoring, and optimizing pilot-scale and full-scale MTBE biobarrier systems. It is largely empirically based, although the design approach does rely on simple engineering calculations. The paradigm emphasizes gas injection–based oxygen delivery schemes, although many of the steps would be common to other methods of delivering oxygen to aquifers. 相似文献
438.
A reinterpretation of the great pit at Hofstaðir,Iceland using sediment thin section micromorphology
The site at Hofstaðir in northeast Iceland has been central to the debate on pre-Christian Norse temples and temple-farm complexes throughout the Scandinavian world. Critical to an understanding of the site have been the various and conflicting interpretations of the great pit feature, which have included the hypotheses that it was intentionally made for the disposal of rubbish after temple feasts, that it was a cooking pit for large-scale food preparation within a temple–farm complex, and that it was the location of a rubbish tip for ordinary farmstead waste materials. In this article we test these competing hypotheses using the technique of thin section micromorphology. These analyses represent the first application of micromorphology to questions of archaeological site formation processes in Iceland, a volcanic island with commonly occurring Andisols. Although this soil type poses new challenges to archaeological soil micromorphology, it was found that pedofeatures, microstructures, and anthropogenic inclusions provide a basis for interpreting site formation processes on Andisols as on other soil types. We conclude that the pit feature had its origins as a sunken-featured building and that the hollow created by the building's abandonment and collapse was later filled with domestic farmstead waste. © 1999 John Wiley & Sons, Inc. 相似文献
439.
Yasushi Ikebe Karen Leighly Yasuo Tanaka Takao Nakagawa Yuichi Terashima Stefanie Komossa 《Monthly notices of the Royal Astronomical Society》2000,316(2):433-441
We present new data taken at 850 μm with SCUBA at the James Clerk Maxwell Telescope for a sample of 19 luminous infrared galaxies. Fourteen galaxies were detected. We have used these data, together with fluxes at 25, 60 and 100 μm from IRAS , to model the dust emission. We find that the emission from most galaxies can be described by an optically thin, single temperature dust model with an exponent of the dust extinction coefficient ( k λ ∝ λ − β ) of β ≃1.4–2. A lower β ≃1 is required to model the dust emission from two of the galaxies, Arp 220 and NGC 4418. We discuss various possibilities for this difference and conclude that the most likely is a high dust opacity. In addition, we compare the molecular gas mass derived from the dust emission, M 850 μm , with the molecular gas mass derived from the CO emission, M CO , and find that M CO is on average a factor 2–3 higher than M 850 μm . 相似文献
440.
Testing the utility of structure‐from‐motion photogrammetry reconstructions using small unmanned aerial vehicles and ground photography to estimate the extent of upland soil erosion 总被引:1,自引:0,他引:1
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Miriam Glendell Gareth McShane Luke Farrow Mike R. James John Quinton Karen Anderson Martin Evans Pia Benaud Barry Rawlins David Morgan Lee Jones Matthew Kirkham Leon DeBell Timothy A. Quine Murray Lark Jane Rickson Richard E. Brazier 《地球表面变化过程与地形》2017,42(12):1860-1871
Quantifying the extent of soil erosion at a fine spatial resolution can be time consuming and costly; however, proximal remote sensing approaches to collect topographic data present an emerging alternative for quantifying soil volumes lost via erosion. Herein we compare terrestrial laser scanning (TLS), and both unmanned aerial vehicle (UAV) and ground photography (GP) structure‐from‐motion (SfM) derived topography. We compare the cost‐effectiveness and accuracy of both SfM techniques to TLS for erosion gully surveying in upland landscapes, treating TLS as a benchmark. Further, we quantify volumetric soil loss estimates from upland gullies using digital surface models derived by each technique and subtracted from an interpolated pre‐erosion surface. Soil loss estimates from UAV and GP SfM reconstructions were comparable to those from TLS, whereby the slopes of the relationship between all three techniques were not significantly different from 1:1 line. Only for the TLS to GP comparison was the intercept significantly different from zero, showing that GP is more capable of measuring the volumes of very small erosion features. In terms of cost‐effectiveness in data collection and processing time, both UAV and GP were comparable with the TLS on a per‐site basis (13.4 and 8.2 person‐hours versus 13.4 for TLS); however, GP was less suitable for surveying larger areas (127 person‐hours per ha?1 versus 4.5 for UAV and 3.9 for TLS). Annual repeat surveys using GP were capable of detecting mean vertical erosion change on peaty soils. These first published estimates of whole gully erosion rates (0.077 m a?1) suggest that combined erosion rates on gully floors and walls are around three times the value of previous estimates, which largely characterize wind and rainsplash erosion of gully walls. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献