Gaseous Emissions from Vehicles in a Traffic Tunnel in Vancouver,British Columbia

ABSTRACT

In August 1995, measurements of CO, NO_x, speciated nonmethane hydrocarbons (NMHC), and CO₂ were made in Vancouver's Cassiar Connector, a 730-m-long level-grade highway traffic tunnel. Two characteristics of the Vancouver setting are the presence of many propane vehicles and a mandatory inspection and maintenance (I/M) program. Although the driving conditions and vehicle fleets are otherwise outwardly similar to those of recent Tuscarora-tunnel studies, CO/NO ratios at the Cassiar Connector are significantly lower than those measured at Tuscarora. The Cassiar measurements are consistent with the MOBILE5A mobile emissions model predictions. The Canadian version of MOBILE5A—known as MOBILE5C—gives nearly identical results, indicating that differences in Canadian and U.S. emission standards cannot explain differences between Cassiar and U.S. tunnels. Considering the modeling results as well as measured ethene/acetylene ratios indicative of noncatalyst vehicles, it appears that vehicle deterioration remains the major issue in in-use vehicle emissions—even in Vancouver, where there is a mandatory loaded-mode I/M program.     

Untersuchung von Abfällen mit biologischen Testverfahren zur Bewertung der Wassergefährdung

Wastes from three different types of waste treatment facilities were examined with bioassays to determine their hazard potential to waters (→Part I). All examined wastes showed toxic effects and have to be classified as hazardous to waters according to section 19g of the German Federal Water Management Act. The toxicity is probably caused by heavy metals in the leachates, especially copper. An evaluation pattern to classify wastes in the German system of Water Hazard Classes is presented. According to this proposal, a classification of the examined wastes into Water Hazard Class 1 seems to be appropriate. This classification does not describe the hazards resulting from the regular disposal on a landfill or from the utilisation of the treated wastes.     

Transformation of diclofenac by the indigenous microflora of river sediments and identification of a major intermediate

Diclofenac is a non-steroidal anti-inflammatory drug, which tends to be relatively persistent in the environment. Now, a fixed-bed column bioreactor filled with sediment from the creek Münzbach (Freiberg/Saxony) under aerobic conditions showed rapid removal of diclofenac in a concentration range of 3-35 microM without previous adaptation. The conversion of higher concentrations up to 260 microM was accompanied by conspicuously decreased turnover rates indicating a toxic effect of this drug or its resulting metabolic burden on the indigenous microflora. A major metabolite occurred transiently and was identified by NMR and MS to be the p-benzoquinone imine of 5-hydroxydiclofenac. Abiotic adsorption to the biofilm was shown to determine the further fate of this reactive product of 5-hydroxydiclofenac (aut-)oxidation. The apparent lack of a degradative potential for this compound as well as the failure to detect an enrichment of diclofenac-depleting microbial activity both indicate a cometabolic nature of diclofenac transformation. 4'-Hydroxy-diclofenac, the favoured transformation product of eucaryotic diclofenac metabolism, could not be identified. The ability to convert diclofenac was shown to be widespread among biofilms from different river sediments, but measured rates obviously do not correlate with the total microbial activity. In addition, application of sediments from locations exposed to communal waste water effluents did not indicate any form of adaptation measured as an increased specific diclofenac depletion rate.     

Local authorities and climate protection in the European union: Putting subsidiarity into practice?

Abstract

Although intrinsically a global environmental concern, the climate change issue has a number of implications for local authorities. Within the European Union (EU), the remit of local authorities in—‐for abatement policies—the crucial areas of energy and transport policy varies considerably, as does their commitment to environmental action more generally. This paper examines the role of local authorities in climate protection within a framework of global, EU and national action, through examples of local strategies from Germany, Italy, Spain, Sweden and the UK. The paper finds positive instances of action in all countries, but points to unsympathetic policy frameworks both at national and EU level, such as budget constraints imposed on local authorities, the pursuit of low energy prices combined with a resistance to impose carbon taxes, a lack of energy efficiency standards and insufficient support for public transport.     

The influence of metabolically engineered glucosinolates profiles in Arabidopsis thaliana on Plutella xylostella preference and performance

The oviposition preference and larval performance of the diamondback moth (DBM), Plutella xylostella, was studied using Arabidopsis thaliana plants with modified glucosinolate (GS) profiles containing novel GSs as a result of the introduction of individual CYP79 genes. The insect parameters were determined in a series of bioassays. The GS content of the plants as well as the number of trichomes were measured. Multivariate analysis was used to determine the possible relationships among insect and plant variables. The novel GSs in the tested lines did not appear to have any unequivocal effect on the DBM. Instead, the plant characteristics that affected larval performance and larval preference did not influence oviposition preference. Trichomes did not affect oviposition, but influenced larval parameters negatively. Although the tested A. thaliana lines had earlier been shown to influence disease resistance, in this study no clear results were found for P. xylostella.     

Stakeholder perceptions of grassland ecosystem services in relation to knowledge on soil fertility and biodiversity

The concept of ecosystem services is increasingly being used by scientists and policy makers. However, most studies in this area have focussed on factors that regulate ecosystem functions (i.e. the potential to deliver ecosystem services) or the supply of ecosystem services. In contrast, demand for ecosystem services (i.e. the needs of beneficiaries) or understanding of the concept and the relative ranking of different ecosystem services by beneficiaries has received limited attention. The aim of this study was to identify in three European mountain regions the ecosystem services of grassland that different stakeholders identify (which ecosystem services for whom), the relative rankings of these ecosystem services, and how stakeholders perceive the provision of these ecosystem services to be related to agricultural activities. We found differences: (1) between farmers?? perceptions of ecosystem services across regions and (2) within regions, between knowledge of ecosystem services gained by regional experts through education and farmers?? local field-based knowledge. Nevertheless, we identified a common set of ecosystem services that were considered important by stakeholders across the three regions, including soil stability, water quantity and quality, forage quality, conservation of botanical diversity, aesthetics and recreation (for regional experts), and forage quantity and aesthetic (for local farmers). We observed two contrasting stakeholder representations of the effects of agricultural management on ecosystem services delivery, one negative and the other positive (considering low to medium management intensity). These representations were determined by stakeholders?? perceptions of the relationships between soil fertility and biodiversity. Overall, differences in perceptions highlighted in this study show that practitioners, policy makers and researchers should be more explicit in their uses of the ecosystem services concept in order to be correctly understood and to foster improved communication among stakeholders.     

Reference conditions for rivers of the German Baltic Sea catchment: reconstructing nutrient regimes using the model MONERIS

We introduce an approach for establishing reference conditions (RC) for rivers of the German Baltic Sea catchment, based on predictive modelling. An extensive data set of statistics from the year 1880 was coupled with literature data, providing a comprehensive basis for the calculation of regional historical nutrient emissions into rivers, river nutrient concentrations, and nutrient loading into the sea. Four different scenarios were calculated: scenario 1 assumed RC following previously established criteria for lakes (Poikane et al. in Environ Manag 45(6):1286–1298, 2010), scenario 4 applied the nutrient emission conditions of 1880 (considering non-intensive land usage, the presence of tile drainage systems, sewer systems, and the human population from 1880), and scenarios 2 and 3 considered intermediate conditions. Our results showed that nutrient emissions from scenario 1 accounted for approximately one-tenth of the currently observed total nitrogen (TN) and total phosphorus (TP) emissions. The nutrient emissions calculated for 1880 (scenario 4) were found to be 47 % (TN) and 55 % (TP) higher than those calculated considering reference lake conditions (scenario 1). Our results suggest that RC nutrient concentrations in rivers in the German Baltic Sea catchment were clearly below 0.05 mg/l for TP and 1 mg/l for TN. This range is in accordance with historical and calculated pristine nutrient concentrations from other rivers in similar catchments.     

Consumer-resource body-size relationships in natural food webs

It has been suggested that differences in body size between consumer and resource species may have important implications for interaction strengths, population dynamics, and eventually food web structure, function, and evolution. Still, the general distribution of consumer-'resource body-size ratios in real ecosystems, and whether they vary systematically among habitats or broad taxonomic groups, is poorly understood. Using a unique global database on consumer and resource body sizes, we show that the mean body-size ratios of aquatic herbivorous and detritivorous consumers are several orders of magnitude larger than those of carnivorous predators. Carnivorous predator-prey body-size ratios vary across different habitats and predator and prey types (invertebrates, ectotherm, and endotherm vertebrates). Predator-prey body-size ratios are on average significantly higher (1) in freshwater habitats than in marine or terrestrial habitats, (2) for vertebrate than for invertebrate predators, and (3) for invertebrate than for ectotherm vertebrate prey. If recent studies that relate body-size ratios to interaction strengths are general, our results suggest that mean consumer-resource interaction strengths may vary systematically across different habitat categories and consumer types.     

Ecosystem approach to harvesting in the Arctic: Walking the tightrope between exploitation and conservation in the Barents Sea

Projecting the consequences of warming and sea-ice loss for Arctic marine food web and fisheries is challenging due to the intricate relationships between biology and ice. We used StrathE2EPolar, an end-to-end (microbes-to-megafauna) food web model incorporating ice-dependencies to simulate climate-fisheries interactions in the Barents Sea. The model was driven by output from the NEMO-MEDUSA earth system model, assuming RCP 8.5 atmospheric forcing. The Barents Sea was projected to be > 95% ice-free all year-round by the 2040s compared to > 50% in the 2010s, and approximately 2 °C warmer. Fisheries management reference points (F_MSY and B_MSY) for demersal fish (cod, haddock) were projected to increase by around 6%, indicating higher productivity. However, planktivorous fish (capelin, herring) reference points were projected to decrease by 15%, and upper trophic levels (birds, mammals) were strongly sensitive to planktivorous fish harvesting. The results indicate difficult trade-offs ahead, between harvesting and conservation of ecosystem structure and function.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01616-9.