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451.
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
452.
Louise C. Ross Gunnar Austrheim Leif-Jarle Asheim Gunnar Bjarnason Jon Feilberg Anna Maria Fosaa Alison J. Hester Øystein Holand Ingibjörg S. Jónsdóttir Lis E. Mortensen Atle Mysterud Erla Olsen Anders Skonhoft James D. M. Speed Geir Steinheim Des B. A. Thompson Anna Gudrún Thórhallsdóttir 《Ambio》2016,45(5):551-566
453.
Shawn Burnell Jon Spitzinger Peng Jin Jay Erickson Erin Hauber Denice Nelson 《补救:环境净化治理成本、技术与工艺杂志》2013,23(1):85-101
Over the past decade, we have learned a number of critical lessons surrounding carbon substrate handling while operating and maintaining hundreds of enhanced in situ biological remedies. The same qualities that make these substrates effective can also cause biofouling of the mixing system, piping infrastructure, and remediation wells. Managing biofouling is a key piece of a successful remedy and requires a unique set of design principles. Small decreases in injection rates can have considerable impacts to life‐cycle costs and performance caused by decreased substrate distribution and longer injection time frames, resulting in the need for system cleaning, well rehabilitation, and even well replacement. Biofouling can impair performance in any size system, but effects are often magnified by large injection volumes and extended time frames. Design should be considered in all stages of the anaerobic enhanced in situ bioremediation life cycle, particularly related to reagent mixing, storage, and residence time within the system. By understanding the fundamental mechanisms of biofouling, practitioners can make operational adjustments to enhance remedy performance by considering potential biofouling controls in the design; balancing site‐specific strategy and diagnostics; and proactively adjusting and fine tuning control/prevention technology and methodology. Ultimately, a combination of chemical and physical methods may be required to operate a carbon handling system over the long term; however, the operational costs can be greatly reduced and delivery efficiency increased if these methods are understood during the design phase. © 2013 Wiley Periodicals, Inc. 相似文献
454.
Forest Fragmentation and Landscape Transformation in a Reindeer Husbandry Area in Sweden 总被引:1,自引:0,他引:1
Reindeer husbandry and forestry are two main land users in boreal forests in northern Sweden. Modern forestry has numerous
negative effects on the ground-growing and arboreal lichens that are crucial winter resources for reindeer husbandry. Using
digitized historical maps, we examined changes in the forest landscape structure during the past 100 years, and estimated
corresponding changes in suitability of forest landscape mosaics for the reindeer winter grazing. Cover of old coniferous
forests, a key habitat type of reindeer herding system, showed a strong decrease during the study period, whereas clear-cutting
and young forests increased rapidly in the latter half of the 20th century. The dominance of young forests and fragmentation
of old-growth forests (decreased patch sizes and increased isolation) reflect decreased amount of arboreal lichens as well
as a lowered ability of the landscape to sustain long-term persistence of lichens. The results further showed that variation
in ground lichen cover among sites was mainly related to soil moisture conditions, recent disturbances, such as soil scarification
and prescribed burning, and possibly also to forest history. In general, the results suggest that the composition and configuration
of the forest landscape mosaic has become less suitable for sustainable reindeer husbandry. 相似文献
455.
Native Perennial Forb Variation Between Mountain Big Sagebrush and Wyoming Big Sagebrush Plant Communities 总被引:1,自引:0,他引:1
Big sagebrush (Artemisia tridentata Nutt.) occupies large portions of the western United States and provides valuable wildlife habitat. However, information
is lacking quantifying differences in native perennial forb characteristics between mountain big sagebrush [A. tridentata spp. vaseyana (Rydb.) Beetle] and Wyoming big sagebrush [A. tridentata spp. wyomingensis (Beetle & A. Young) S.L. Welsh] plant communities. This information is critical to accurately evaluate the quality of habitat
and forage that these communities can produce because many wildlife species consume large quantities of native perennial forbs
and depend on them for hiding cover. To compare native perennial forb characteristics on sites dominated by these two subspecies
of big sagebrush, we sampled 106 intact big sagebrush plant communities. Mountain big sagebrush plant communities produced
almost 4.5-fold more native perennial forb biomass and had greater native perennial forb species richness and diversity compared
to Wyoming big sagebrush plant communities (P < 0.001). Nonmetric multidimensional scaling (NMS) and the multiple-response permutation procedure (MRPP) demonstrated that
native perennial forb composition varied between these plant communities (P < 0.001). Native perennial forb composition was more similar within plant communities grouped by big sagebrush subspecies
than expected by chance (A = 0.112) and composition varied between community groups (P < 0.001). Indicator analysis did not identify any perennial forbs that were completely exclusive and faithful, but did identify
several perennial forbs that were relatively good indicators of either mountain big sagebrush or Wyoming big sagebrush plant
communities. Our results suggest that management plans and habitat guidelines should recognize differences in native perennial
forb characteristics between mountain and Wyoming big sagebrush plant communities. 相似文献
456.
In this paper, a simple model for analysing variability in radon concentrations in homes is tested. The approach used here involves two error components, representing additive and multiplicative errors, together with variation between-houses. We use a Bayesian approach for our analysis and apply this model to two datasets of repeat radon measurements in homes; one based on 3-month long measurements for which the original measurements were close to the current UK Radon Action Level (200 Bq m−3), and the other based on 6-month measurement data (from regional and national surveys), for which the original measurements cover a wide range of radon concentrations, down to very low levels. The model with two error components provides a better fit to these datasets than does a model based on solely multiplicative errors. 相似文献
457.
Extensive research has been done on the 'high politics' of negotiations of international environmental agreements. However, little attention has been paid to the effectiveness of their implementation after coming into force. Effectiveness cannot be easily measured, since different stakeholders use different criteria as the basis of their opinion. The purpose of this study is to investigate discourses on the effectiveness of an international environmental regime. The regime chosen is the Mediterranean Action Plan (MAP) - and its legal framework, the Barcelona Convention - which was established in 1975 under the aegis of the United Nations Environment Programme (UNEP). Q methodology was used to reveal discourses on the effectiveness of UNEP/MAP. After collecting relevant literature and identifying the stakeholders, 25 in-depth interviews were conducted. The stakeholders were from the Secretariat of the Convention, academia, NGO workers, and others that studied or knew the subject well. From these interviews 294 statements were extracted, from which 44 were finally selected to be used in the Q study. The interviewees were approached for the second time to complete the Q sorts. This study revealed four distinct discourses concerning the effectiveness of international environmental regimes. It concludes that there is no one 'right' way of defining effectiveness and that no approach can provide more than a partial evaluation of the overall effectiveness of a regime. 相似文献
458.
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
459.
Brian S. Helms Jon E. Schoonover Jack W. Feminella 《Journal of the American Water Resources Association》2009,45(1):157-169
Abstract: We evaluated the impact of land cover on fish assemblages by examining relationships between stream hydrology, physicochemistry, and instream habitat and their association with fish responses in streams draining 18 watersheds of the Lower Piedmont of western Georgia. Several important relationships between land use and physicochemical, hydrological, and habitat parameters were observed, particularly higher frequency of spate flows, water temperatures, and lower dissolved oxygen (DO) with percentage impervious surface (IS) cover, higher habitat quality with percentage forest cover, and elevated suspended solid concentrations with percentage pasture cover. Fish assemblages were largely explained by physicochemical and hydrological rather than habitat variables. Specifically, fish species diversity, richness, and biotic integrity were lower in streams that received high frequency of spate flows. Also, overall fish assemblage structure as determined by nonmetric multidimensional scaling was best described by total dissolved solids (TDS) and DO, with high TDS and low DO streams containing sunfish‐based assemblages and low TDS and high DO streams containing minnow‐based assemblages. Our results suggest that altered hydrological and physicochemical conditions, induced largely by IS, may be a strong determinant of fish assemblage structure in these lowland streams and allow for a more mechanistic understanding of how land use ultimately affects these systems. 相似文献
460.
Rural industries and water pollution in China 总被引:10,自引:0,他引:10
Water pollution from small rural industries is a serious problem throughout China. Over half of all river sections monitored for water quality are rated as being unsafe for human contact, and this pollution is estimated to cost several per cent of GDP. While China has some of the toughest environmental protection laws in the world, the implementation of these laws in rural areas is not effective. This paper explains the reasons for this implementation gap. It argues that the factors that have underpinned the economic success of rural industry are precisely the same factors that cause water pollution from rural industry to remain such a serious problem in China. This means that the control of rural water pollution is not simply a technical problem of designing a more appropriate governance system, or finding better policy instruments or more funding. Instead, solutions lie in changes in the model that underpins rural development in China. 相似文献