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951.
Corporate social performance (CSP) is assumed to have a positive impact on macroeconomic sustainability, but empirical evidence of this impact is absent in the literature. The objective of this paper is to investigate the macro impacts of CSP. We first establish a conceptual framework on the relationship between CSP at the individual business level and sustainability at the macro level. Next, we empirically test the relationship between (averaged) CSP scores and greenhouse gas emissions at the macro level for 22 countries during 2004–2011. We use Granger causality tests to check for Granger causality. The estimation results show that CSP reduces greenhouse gas emissions, but the long-term effect is rather modest.  相似文献   
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The series of papers in this issue of AMBIO represent technical presentations made at the 7th International Phosphorus Workshop (IPW7), held in September, 2013 in Uppsala, Sweden. At that meeting, the 150 delegates were involved in round table discussions on major, predetermined themes facing the management of agricultural phosphorus (P) for optimum production goals with minimal water quality impairment. The six themes were (1) P management in a changing world; (2) transport pathways of P from soil to water; (3) monitoring, modeling, and communication; (4) importance of manure and agricultural production systems for P management; (5) identification of appropriate mitigation measures for reduction of P loss; and (6) implementation of mitigation strategies to reduce P loss. This paper details the major challenges and research needs that were identified for each theme and identifies a future roadmap for catchment management that cost-effectively minimizes P loss from agricultural activities.  相似文献   
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956.
This study examines the role of dorsiventral leaf measurements in reflectance-based air quality estimation. The dorsiventral asymmetry is used to describe the difference between the upper (adaxial) and lower (abaxial) leaf side. Spectral characteristics of dorsiventral asymmetry and both adaxial and abaxial leaf reflectance are investigated for a typical dicotyledonous species Carpinus betulus used in an urban environment. The link with traffic-related air pollution is established and the potential for monitoring of air quality is evaluated. We conclude that dorsiventral reflectance asymmetry is a factor that should not be ignored in canopy measurements and modeling. On the other hand, the benefits of dorsiventral asymmetry indices as a tool for reflectance-based air quality seem limited.  相似文献   
957.
The success of the Clean Development Mechanism of the Kyoto Protocol to reduce global greenhouse gas emissions requires that there are scientifically sound and usable measurement methods for the emission baseline. Three different methods are investigated in the context of China’s electrical sector: simulation with dispatch analysis, decomposition analysis, and operating and build margin analysis. It is found that dispatch analysis is the best method available as it is able to consider important regional and temporal dimensions, while decomposition analysis can help quantify the potential effects of different energy and environment policy choices.  相似文献   
958.
River Benue, the second largest river in Nigeria, serves as the major source of municipal water supplies for towns and villages along its course. Water samples from the river were collected at ten stations in the Makurdi metropolitan area (7°44 N, 8°32 E) in Benue State, Central Nigeria, for 12 months and analyzed for their heavy metals concentration, along with other water-quality parameters such as turbidity, pH, total dissolved solids and total solids. The results revealed that the mean concentrations of heavy metals in the river was in the following ascending order, Cd < Cu < Zn < Mn < Pb < Cr < Fe. The levels of most of the parameters determined, with the exception of Cd, Cr and Pb were, generally, within acceptable limits for drinking water. From the present study, it is concluded that the River Benue is only moderately contaminated with regard to heavy metals, in the Makurdi metropolitan area.  相似文献   
959.
Inorganic arsenic is a chronic exposure carcinogen. Analysis of UK baby rice revealed a median inorganic arsenic content (n = 17) of 0.11 mg/kg. By plotting inorganic arsenic against total arsenic, it was found that inorganic concentrations increased linearly up to 0.25 mg/kg total arsenic, then plateaued at 0.16 mg/kg at higher total arsenic concentrations. Inorganic arsenic intake by babies (4-12 months) was considered with respect to current dietary ingestion regulations. It was found that 35% of the baby rice samples analysed would be illegal for sale in China which has regulatory limit of 0.15 mg/kg inorganic arsenic. EU and US food regulations on arsenic are non-existent. When baby inorganic arsenic intake from rice was considered, median consumption (expressed as μg/kg/d) was higher than drinking water maximum exposures predicted for adults in these regions when water intake was expressed on a bodyweight basis.  相似文献   
960.
This study determines spatial trends and congener patterns of 2378-substituted polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in surficial sediments of Lakes Erie and Ontario. Sediments are enriched in 2378-PCDFs in Lake Ontario, and the PCDD/F concentrations increased from shallow near-shore sediments towards deep-water depositional zone sediments. In Lake Erie, sediments were dominated by octachlorodibenzo-p-dioxin, and the highest PCDD/F concentrations were observed in the western basin and the southern shoreline of the central basin with a decrease towards the eastern basin and the northern shoreline of the central basin. Principal components analysis revealed that chemical manufacture and disposal of chemical waste along the Niagara River has been a major PCDD/F source to Lake Ontario; while PCDD/Fs in Lake Erie are from multiple sources including industrial sources along the Detroit River, major tributaries along the southern shoreline of the lake, and atmospherically-derived material from the upper lakes and connecting channels.  相似文献   
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