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991.
Peter Roebeling Miguel Saraiva Anna Palla Ilaria Gnecco Carla Teotónio Teresa Fidelis 《Journal of Environmental Planning and Management》2017,60(3):482-499
Urban green/blue spaces are put under pressure as urban areas grow, develop and evolve. It is increasingly recognized, however, that green/blue spaces provide important ecosystem services, stimulate higher real estate prices and prevent flooding problems. This paper aims to assess and compare the socio-economic impacts of potential green/blue space, urban residential and road infrastructure development scenarios in the Lyon Confluence project area (France), using the Sustainable Urbanizing Landscape Development (SULD) hedonic pricing simulation model. Results show four major tendencies regarding the value-added of green/blue spaces in urban landscapes: (1) cities become more compact; (2) population densities increase; (3) real estate values rise; and (4) demographic distribution patterns change. The magnitude of these impacts depends, however, on the quality and size of the intervention, the social classes attracted to the intervention area and on the location of the intervention relative to existing residential areas, urban centres, road infrastructure and environmental amenities. 相似文献
992.
Control of wild animals may give rise to controversy, as is seen in the case of badger control to manage TB in cattle in the UK. However, it is striking that concerns about the potential suffering of the affected animals themselves are often given little attention or completely ignored in policies aimed at dealing with wild animals. McCulloch and Reiss argue that this could be remedied by means of a “mandatory application of formal and systematic Animal Welfare Impact Assessment (AWIA)”. Optimistically, they consider that an AWIA could help to resolve controversies involving wild animals. The aim of this paper is to evaluate the potential of AWIA. We begin by showing how ideas akin to AWIA already play a significant role in other animal ethics controversies, particularly those concerning laboratory animal use and livestock production; and we bring in lessons learnt from these controversies. Then we comment on the suggested development and application of AWIA in the case of badger control. Finally, we discuss the prospects of applying AWIA to other sorts of wild animal controversy. We argue that the AIWA, as developed by McCulloch and Reiss, relies on several dubious premises, including that killing is a welfare issue. Furthermore, we argue that AWIA is unlikely to prevent serious moral disagreements over how to weigh concerns about wild animals against priorities in human health, the health of domestic and farm animals, and biodiversity, but that it may nonetheless serve to limit harms imposed on the wild animals. 相似文献
993.
Effects of Urbanization on Flow Duration and Stream Flashiness: A Case Study of Puget Sound Streams,Western Washington,USA 下载免费PDF全文
Tyler T. Rosburg Peter A. Nelson Brian P. Bledsoe 《Journal of the American Water Resources Association》2017,53(2):493-507
The overall influence of urbanization on how flows of different frequency might change over time, while important in hydrologic design, remains imprecisely known. In this study, we investigate the effects of urbanization on flow duration curves (FDCs) and flow variability through a case study of eight watersheds that underwent different amounts of growth, in the Puget Sound region in Western Washington State, United States. We computed annual FDCs from flow records spanning 1960‐2010 and, after accounting for the effects of precipitation, we conducted statistical trend analyses on flow metrics to quantify how key FDC percentiles changed with time in response to urbanization. In the urban watersheds, the entire FDC tended to increase in magnitude of flow, especially the 95th‐99th percentile of the daily mean flow series, which increased by an average of 43%. Stream flashiness in urban watersheds was found to increase by an average of 70%. The increases in FDC magnitude and flashiness in urbanizing watersheds are most likely a result of increasing watershed imperviousness and altered hydrologic routing. Rural watersheds were found to have decreasing FDC magnitude over the same time period, which is possibly due to anthropogenic extractions of groundwater, and increasing stream flashiness, which is likely a result of reductions in base flow and increasing precipitation intensity and variability. 相似文献
994.
Peter Jansen Jan van der Stoep Jozef Keulartz Henk Jochemsen 《Journal of Environmental Policy & Planning》2017,19(2):197-213
Based on in-depth interviews, this article presents findings of a study centred on public communication regarding Tiengemeten, a Dutch island previously occupied by farmers. An answer is sought to the question of how visitors to Tiengemeten evaluate, according to their own experiences, the discourse of people involved in Tiengemeten from a policy and communication perspective. This study showed that visitors’ experiences do not always match the emotions appealed to in public communication materials. It is also suggested that people involved from a policy and communication perspective should refrain from using ‘heavily value-laden’ phraseology. For reasons of trust, this article suggests aligning public communication with genuine experiences of visitors. This is also necessary for avoiding scepticism of visitors as policy makers and communication professionals run a risk that public communication regarding nature becomes counterproductive. 相似文献
995.
996.
Since their invasion into the Great Lakes, zebra mussels, Dreissena polymorpha, have increased the water clarity in Lake St. Clair and Lake Erie due to their extensive particle filtration. Because these particles contain sorbed contaminants, the potential for contaminant accumulation from both suspended sediment and algae were examined. Sediment or algae were dosed with selected radiolabeled polycyclic aromatic hydrocarbon congeners and/or hexachlorobiphenyl (HCBP). Assimilation efficiencies were measured and depended on food quality. Zebra mussels, 17 ± 2 mm long, assimilated 58.3 ± 13.5% of the pyrene and 44.7 ± 5.8% of the benzo(a)pyrene (BaP) from sediment particles with a particle clearance rate of 493 – 897 ml/g tissue/h. However, assimilation efficiencies were 91.7 ± 3.7% for pyrene, 91.9 ± 1.4% for BaP, 96.6 ± 1.4% for chrysene, and 97.7 ± 0.5% for HCBP from suspended algae. Algal particle clearance rates for the mussels ranged from 47 – 143 ml/g tissue/h. Thus, zebra mussels efficiently accumulated non-polar contaminants sorbed to algae, while a smaller fraction of the sediment-associated contaminant was bioavailable. Furthermore, the contaminants sorbed onto suspended sediment particles were quickly removed from the water and deposited as pseudofeces. The pseudofeces production was positively correlated with filtration rate and suspended particle concentrations. 相似文献
997.
Phosphine by bio-corrosion of phosphide-rich iron 总被引:1,自引:0,他引:1
Dietmar Glindemann Frank Eismann Armin Bergmann Peter Kuschk Ulrich Stottmeister 《Environmental science and pollution research international》1998,5(2):71-74
Phosphine is a toxic agent and part of the phosphorus cycle. A hitherto unknown formation mechanism for phosphine in the environment was investigated. When iron samples containing iron phosphide were incubated in corrosive aquatic media affected by microbial metabolites, phosphine was liberated and measured by gas chromatography. Iron liberates phosphine especially in anoxic aquatic media under the influence of sulfide and an acidic pH. A phosphine-forming mechanism is suggested: Phosphate, an impurity of iron containing minerals, is reduced abioticly to iron phosphide. When iron is exposed to the environment (e.g. as outdoor equipment, scrap, contamination in iron milled food or as iron meteorites) and corrodes, the iron phosphide present in the iron is suspended in the medium and can hydrolyze to phosphine. Phosphine can accumulate to measurable quantities in anoxic microbial media, accelerating corrosion and preserving the phosphine formed from oxidation. 相似文献
998.
Appelt Jonas L. Saphangthong Thatheva Malek Žiga Verburg Peter H. van Vliet Jasper 《Regional Environmental Change》2023,23(3):1-11
Regional Environmental Change - Understanding popular attitudes to climate change can be important in developing effective climate adaptation responses. However, in the Pacific region, which is at... 相似文献
999.
Analysis of macroinvertebrate assemblages in relation to environmental gradients among lotic habitats of California's Central Valley 总被引:3,自引:0,他引:3
Griffith MB Husby P Hall RK Kaufmann PR Hill BH 《Environmental monitoring and assessment》2003,82(3):281-309
We assessed relationships between environmental characteristicsand macroinvertebrate assemblages in lotic habitats of California's Central Valley with community metric and multivariate statistical approaches. Using canonical ordinationanalyses, we contrasted results when assemblage structure was assessed with macroinvertebrate metrics, as suggested for use inindices of biotic integrity, or with genera abundances. Our objectives were to identify metrics or taxa diagnostic of loticenvironmental stressors and compare the capacity of theseapproaches to detect stressors in order to suggest how they mightbe used to diagnose stressors. For macroinvertebrate metrics,redundancy analysis (RDA) extracted three axes correlated withchannel morphology and substrates. For genera abundances, canonical correspondence analysis (CCA) extracted two axescorrelated with soluble salts and with channel morphology andsubstrates but did not separate these gradients onto differentaxes. Cluster analyses identified five RDA and five CCA sitegroups, which exhibited differences for environmental variables,metrics, or genera abundances, and agreement between the analysesin partitioning of sites was greater than if sites were partitioned randomly. These approaches differ in their abilityto detect environmental stressors, because they measure differentaspects of assemblages and would be complementary in design ofnew metrics diagnostic of stressors. 相似文献
1000.
This study evaluates the spatial patterns of land occupation and their relationship to water quality in the Cuiabá River watershed, one of the main affluents of the Pantanal floodplain. The impact of farming and other land occupation forms were studied using a three year time series. Monitoring included 15 parameters at 21 stations with a total of 1266 different samples. Ten stations along the Cuiabá River were ordinated by Principal Component Analysis (PCA). For an exploratory analysis in the spatial domain, sub-basins of the Cuiabá watershed were classified according to mean concentrations of selected water quality parameters. Supervised classification of digital Landsat ETM imagery and standard GIS techniques were applied to parameterize land use and occupation according to a watershed scale. Redundancy Analysis (RDA) was then used to evaluate impacts of environmental and socio-economic factors on water quality.A Cuiabá headwater station only shows slightly elevated total coliform counts and concentrations of nutrients in the river after it passes regions of extensive cattle farming. After the confluence with the Manso River, nutrient and COD concentrations increase significantly, receiving loads from sub-basins under intensive agricultural land use, with mean annual concentrations up to 1.74 mg/L of total nitrogen (Kjedahl). Sub-watersheds with intensive fishing culture activities were shown to have significant impact on nitrogen concentrations, reaching mean concentrations of 2.66 mg/L of total nitrogen in the affluents. Most serious biological and chemical water pollution can be observed at stream outlets in the urban agglomeration of Cuiabá/Várzea Grande. Affluent pollution is reflected in the water quality of the Cuiabá River: subsequent monitoring stations in the urban area are ordinated on a gradient of increasing degradation of chemical and biological water quality. The auto-depuration capacity of the Cuiabá River is intact, but elevated concentrations of Phosphorous and Chemical Oxygen Demand can be observed as far away as the Pantanal floodplain, about 120 km downstream from the urban agglomeration. 相似文献