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611.
612.
Emily Mann Michael A. Long Paul B. Stretesky Margaret Anne Defeyter 《Local Environment》2018,23(10):1008-1022
In response to the problem of holiday hunger, hundreds of local “holiday clubs” have recently been established across the UK. This research examines the spatial relationship between income, childhood deprivation, ethnicity and holiday clubs across 32,844 Lower Super Output Areas (LSOAs) in England to determine if these clubs are currently operating in an inclusive fashion. Data on the location of holiday clubs comes from a national survey. Binary logistic regression results suggest that holiday clubs are likely to operate in economically disadvantaged areas. At the same time, clubs are not distributed equally by ethnicity. That is, holiday clubs operated by voluntary organisations are more likely to be situated in LSOAs that are disproportionately white and English\British and less likely to be situated in LSOAs that are disproportionately ethnic minority. This finding has important implications for the pursuit of holiday clubs as a policy mechanism for addressing access to food in light of the state’s failure to adequately feed all of the country’s children. 相似文献
613.
Jan Anne Annema Carl Koopmans 《Journal of Environmental Planning and Management》2015,58(9):1635-1648
Scientific debates on environmental impacts in cost-benefit analysis (CBA) focus on methodological questions. The literature, however, contains very little information on the influence of these debates on CBAs made in spatial planning practice. In this paper, this gap is filled by a qualitative analysis of 67 CBAs made in the Netherlands between 2000 and 2011. From the literature on environmental valuation, we derive criteria to evaluate the quality of CBA practice, such as completeness and the inclusion of uncertainties. The analysis shows that in many cases relevant environmental effects are omitted or not monetised. Moreover, non-monetised effects are often not included in CBA conclusions. If impacts are monetised, the methods used are frequently not very sophisticated. The consequences of assumptions are often not communicated, for example, where high discount rates make long-term effects seem unimportant. In this research we identify four main points for good practice. 相似文献
614.
Quantifying climate change mitigation potential in the United States Great Plains wetlands for three greenhouse gas emission scenarios 总被引:1,自引:0,他引:1
615.
Potassium silicate drilling fluids(PSDF) are a waste product of the oil and gas industry with potential for use in land reclamation. Few studies have examined the influence of PSDF on abundance and composition of soil bacteria and fungi. Soils from three representative locations for PSDF application in Alberta, Canada, with clay loam, loam and sand textures were studied with applications of unused, used once and used twice PSDF. For all three soils, applying ≥ 40 m3/ha of used PSDF significantly affected the existing soil microbial flora. No microbiota was detected in unused PSDF without soil. Adding used PSDF to soil significantly increased total fungal and aerobic bacterial colony forming units in dilution plate counts, and anaerobic denitrifying bacteria numbers in serial growth experiments.Used PSDF altered bacterial and fungal colony forming unit ratios of all three soils. 相似文献
616.
Potassium silicate drilling fluids (PSDF) are a waste product of the oil and gas industry with potential for use in land reclamation. Few studies have examined the influence of PSDF on abundance and composition of soil bacteria and fungi. Soils from three representative locations for PSDF application in Alberta, Canada, with clay loam, loam and sand textures were studied with applications of unused, used once and used twice PSDF. For all three soils, applying ≥40 m3/ha of used PSDF significantly affected the existing soil microbial flora. No microbiota was detected in unused PSDF without soil. Adding used PSDF to soil significantly increased total fungal and aerobic bacterial colony forming units in dilution plate counts, and anaerobic denitrifying bacteria numbers in serial growth experiments. Used PSDF altered bacterial and fungal colony forming unit ratios of all three soils. 相似文献
617.
618.
The trophic importance of bacteria to harpacticoid copepods in intertidal areas remains poorly understood, and so do the mechanisms of bacterial feeding. It is, for instance, unclear whether harpacticoids directly target bacterial cells or merely co-ingest them with substrates to which bacterial cells may be attached. Here, we investigate bacterial uptake and substrate requirement for four mud intertidal species (Microarthridion littorale, Platychelipus littoralis, Delavalia palustris and Nannopus palustris) by means of 13C-labeled bacteria and biomarker fatty acids (FA). Bacterial uptake strongly depended on grazing on a primary food source but bacterial ingestion rates were low, and no clear indication of copepods directly targeting bacteria was found. Delavalia was the only species that accumulated bacteria-derived FA and gained in polyunsaturated FA (PUFA) probably through bioconversion of bacteria-derived FA. In general, however, our results suggest that bacteria represent a relatively minor and low-quality food for intertidal harpacticoid copepods. 相似文献
619.
620.
Estimating the population size with a behavioral response in capture-recapture experiment 总被引:1,自引:0,他引:1
Yip Paul S.F. Xi Liqun Chao Anne Hwang Wen-Han 《Environmental and Ecological Statistics》2000,7(4):405-414
A new estimating procedure is suggested to estimate the population size in a capture-recapture experiment. The capture intensities for first-capture and recapture are allowed to be different and time dependent but they are assumed to be proportional. It is shown that the information on the proportionality constant is crucial to the estimation of the population size. Sensitivity analysis with a misspecification of the proportionality constant is conducted. The method has also been extended to the case with an unknown proportionality. A real example is given. 相似文献