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181.
Henrike Luhmann Ludwig Theuvsen 《Journal of Agricultural and Environmental Ethics》2017,30(2):241-253
Corporate social responsibility (CSR) has long been an issue for research and practice. More recently, in response to growing public scrutiny, it has also gained importance in the agribusiness sector. Research has highlighted a growing gap between public perceptions of farming and food production processes and the realities of modern agriculture and the food industry. This can threaten the reputation and legitimacy of companies operating in this sector. One proactive means for companies to meet societal expectations is to make an active commitment to society and its needs by implementing a CSR policy. However, there is still no clear definition of CSR, and what important stakeholders actually expect from companies remains largely unknown. This paper focuses on consumers’ perception of CSR. Its objective is to explore a CSR policy design for German agribusiness based on Archie B. Carroll’s famous pyramid model. A consumer survey was conducted to evaluate the CSR demands society places on agribusiness companies. An explorative factor analysis was employed to discover the outline of the construct in the German agribusiness context. The results reveal that Carroll’s model, which was developed from a U.S. point of view, cannot be confirmed for German agribusiness. Instead of Carroll’s four responsibility groups, three areas of responsibility were identified: economic, internal and external. These results have manifold implications for CSR strategies in agribusiness firms and represent an important origin for future investigations on CSR in other countries as well as in specific agribusiness subsectors. 相似文献
182.
Erwin Wauters Karoline D'Haene Ludwig Lauwers 《Journal of Environmental Planning and Management》2017,60(8):1464-1484
We investigate farmers’ intentions to apply biodiversity conservation practices from a psychological perspective, using an adapted version of the theory of planned behaviour (TPB), including group norms and putting emphasis on moral norms and self-identity. The study is based on a quantitative survey (n = 99) in Belgium, analysed using confirmatory factor analyses and path analysis. Results suggest that the impact of attitudes, social norms and perceived behavioural control on intentions is almost fully mediated through moral norms and self-identity. To have a sustained impact, change actions should strive to embed biodiversity conservation into the social norms and into the good farmer identity of the farming community. While acknowledging the explanatory nature of this study, the findings could suggest another view on how to induce behavioural change. 相似文献
183.
Hanwant B. Singh William Viezee Warren B. Johnson Francis L. Ludwig 《Journal of the Air & Waste Management Association (1995)》2013,63(9):1009-1017
A background of ozone (O3), principally of stratospheric origin, is present in the lower free troposphere. Typical mean O3 levels of 50 ppb, 40 ppb, and 30 ppb are encountered here in spring, summer, and fall, respectively. Maximum hourly O3 concentrations which are twice these mean values can be expected. Ozone from the free troposphere is routinely brought down to ground level under turbulent atmospheric conditions. Deep and rapid Intrusions of stratospheric air into the lower troposphere are associated with low-pressure troughs and occur regularly. In the mid troposphere, O3 levels as high as 300 ppb are found within these intrusions. Observational data showing these intrusions, containing high O3 concentrations, to directly reach ground level are currently lacking. Over the United States, an intrusion was present aloft on 8 9% of the days in 1978. The frequency, however, is somewhat reduced in summer and a northward movement is evident. During 1978, no intrusion occurred south of 30°N between June and August and none south of 40 °N in August. The hypothesis that low levels of stratospheric O3 produce disproportionately large amounts of O3 in the polluted atmosphere cannot be supported from currently known chemistry but should be studied further. The experimental technique involving a 7Be/O3 ratio to estimate the daily stratospheric component of ground level O3 is unverified and considered to be inadequate for air quality applications. Estimates resulting from such a technique are considered uncertain by a factor of more than three. Specially designed aircraft studies provide the best means to determine quantitatively the impact of stratospheric O3 on ground level air quality. 相似文献
184.
Winfried Schröder Marcel Holy Roland Pesch Harry Harmens Hilde Fagerli Renate Alber Mahmut Coşkun Ludwig De Temmerman Marina Frolova Laura González-Miqueo Zvonka Jeran Eero Kubin Sébastien Leblond Siiri Liiv Blanka Maňkovská Juha Piispanen Jesús M. Santamaría Primož Simonèiè Ivan Suchara Lilyana Yurukova Harald G. Zechmeister 《Atmospheric environment (Oxford, England : 1994)》2010,44(29):3485-3491
In this study, the indicative value of mosses as biomonitors of atmospheric nitrogen (N) depositions and air concentrations on the one hand and site-specific and regional factors which explain best the total N concentration in mosses on the other hand were investigated for the first time at a European scale using correlation analyses. The analyses included data from mosses collected from 2781 sites across Europe within the framework of the European moss survey 2005/6, which was coordinated by the International Cooperative Programme on Effects of Air Pollution on Natural Vegetation and Crops (ICP Vegetation). Modelled atmospheric N deposition and air concentration data were calculated using the Unified EMEP Model of the European Monitoring and Evaluation Programme (EMEP) of the Convention on Long-range Transboundary Air Pollution (CLRTAP). The modelled deposition and concentration data encompass various N compounds. In order to assess the correlations between moss tissue total N concentrations and the chosen predictors, Spearman rank correlation analysis and Classification and Regression Trees (CART) were applied. The Spearman rank correlation analysis showed that the total N concentration in mosses and modelled N depositions and air concentrations are significantly correlated (0.53 ≤ rs ≤ 0.68, p < 0.001). Correlations with other predictors were lower than 0.55. The CART analysis indicated that the variation in the total N concentration in mosses was best explained by the variation in NH4+ concentrations in air, followed by NO2 concentrations in air, sampled moss species and total dry N deposition. The total N concentrations in mosses mirror land use-related atmospheric concentrations and depositions of N across Europe. In addition to already proven associations to measured N deposition on a local scale the study at hand gives a scientific prove on the association of N concentration in mosses and modelled deposition at the European scale. 相似文献
185.
Characterisation of polymer fractions from waste electrical and electronic equipment (WEEE) and implications for waste management 总被引:2,自引:0,他引:2
There is an increasing interest in the end-of-life management of polymers present in waste electrical and electronic equipment (WEEE). This is mainly due to high recycling and recovery quotas set by the European WEEE directive, which can only be fulfilled by including the plastic fraction in recycling and recovery approaches. Previous studies identified a high material diversity and various contaminants in WEEE plastics, including heavy metals, polybrominated biphenyls (PBB), diphenyl ethers (PBDE), as well as polybrominated dibenzodioxins and dibenzofurans (PBDD/F). These substances are regulated by European directives that limit their levels in marketable products. Consequently, both material diversity and contaminants are strong arguments against material recycling and point to hazardous waste treatment. However, recent developments in the production of flame retardants and electrical and electronic goods aimed to reduce contaminants and material diversity. Thus, the present study summarises updated contaminant levels of plastic fractions of European WEEE, as well as data on materials in waste housing polymers. Material characterisation revealed housing fractions to be interesting sources for polymer recycling, which however has to implement potent material separation and/or bromine elimination techniques. With respect to contaminants, our data indicate an effective phase-out of PBB, but still high levels of PBDE and PBDD/F are found. Sources and implications for the material recycling and thermal recovery approaches are discussed in detail. 相似文献
186.
A mobile sampling and measurement system for the analysis of gaseous and liquid samples in the field was developed. An inductively coupled plasma optical emission spectrometer (ICP-OES), which is built into a van, was used as detector. The analytical system was calibrated with liquid and/or gaseous standards. It was shown that identical mass flows of either gaseous or liquid standards resulted in identical ICP-OES signal intensities. In a field measurement campaign trace and minor elements in the raw flue gas of a waste wood combustor were monitored. Sampling was performed with a highly transport efficient liquid quench system, which allowed to observe temporal variations in the elemental process gas composition. After a change in feedstock an immediate change of the element concentrations in the flue gas was detected. A comparison of the average element concentrations during the combustion of the two feedstocks showed a high reproducibility for matrix elements that are expected to be present in similar concentrations. On the other hand elements that showed strong differences in their concentration in the feedstock were also represented by a higher concentration in the flue gas. Following the temporal variations of different elements revealed strong correlations between a number of elements, such as chlorine with sodium, potassium and zinc, as well as arsenic with lead, and calcium with strontium. 相似文献
187.
Long Phi Hoang Robbert Biesbroek Van Pham Dang Tri Matti Kummu Michelle T. H. van Vliet Rik Leemans Pavel Kabat Fulco Ludwig 《Ambio》2018,47(6):635-649
Climate change and accelerating socioeconomic developments increasingly challenge flood-risk management in the Vietnamese Mekong River Delta—a typical large, economically dynamic and highly vulnerable delta. This study identifies and addresses the emerging challenges for flood-risk management. Furthermore, we identify and analyse response solutions, focusing on meaningful configurations of the individual solutions and how they can be tailored to specific challenges using expert surveys, content analysis techniques and statistical inferences. Our findings show that the challenges for flood-risk management are diverse, but critical challenges predominantly arise from the current governance and institutional settings. The top-three challenges include weak collaboration, conflicting management objectives and low responsiveness to new issues. We identified 114 reported solutions and developed six flood management strategies that are tailored to specific challenges. We conclude that the current technology-centric flood management approach is insufficient given the rapid socioecological changes. This approach therefore should be adapted towards a more balanced management configuration where technical and infrastructural measures are combined with institutional and governance resolutions. Insights from this study contribute to the emerging repertoire of contemporary flood management solutions, especially through their configurations and tailoring to specific challenges. 相似文献
188.
Ludwig De Temmerman Nadia Waegeneers Edward Roekens 《Environmental pollution (Barking, Essex : 1987)》2009,157(4):1337-1341
A biomonitoring network with leafy vegetables was established near a chlor-alkali plant in order to compare the accumulation of mercury to the atmospheric total gaseous mercury (TGM) concentration. Based on data obtained in the reference area the ‘normal’ mercury concentration in vegetables is between 0.6 and 5.4 μg kg−1 FW. The effect detection limits (EDLs) are between 1.2 and 11.0 μg kg−1 FW and the biological detection limits (BDLs), the lowest [TGM] that can be detected significantly, are between 3 and 4 ng m−3. The accumulation rate is lowest for lettuce and high for curly kale that proved to be an excellent accumulator and as such it is very useful for biomonitoring purposes. A comparison made in the 1980s between biomonitoring results with grass and the mercury concentration in leafy vegetables from private gardens nearby proved to be valid when applied to the current biomonitoring results with vegetables. 相似文献
189.
Design criteria for planning urban sewerage/excreta management systems appropriate for developing countries as distinguished from affluent industrialized country practices. 相似文献
190.
Elmer Robinson F. L. Ludwig 《Journal of the Air & Waste Management Association (1995)》2013,63(10):664-669
Size distributions of lead aerosols were obtained for 61 test periods in five urban and two remote areas of the United States. The tests were carried out under a variety of weather conditions in downtown, industrial, and residential locations of Los Angeles, the San Francisco Bay area, Chicago, Cincinnati, Philadelphia, and remote sites in Oklahoma and Arizona. Samples were obtained with a modified Goetz Aerosol spectrometer. Various fractions of the collected samples were analyzed by the dithizone method for lead and the size distributions were calculated on the basis of the chemical determinations. Size distributions were generally similar at the several sampling sites covered in the study. 相似文献