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91.
This paper applies the concept of Hybrid Governance to the analysis of the GASAP (Groupe d’Achats Solidaires de l’Agriculture Paysanne), a solidarity-based producers–consumers network established in Brussels in 2006. The Hybrid Governance concept allows to capture the role of key governance tensions in driving the self-organisation, scaling out and self-reflexive dynamics of Alternative Food Networks (AFNs). The approach provides a multifaceted and sound socio-political account of the ways AFNs arise, self-organise, associate and build networks in the pursuit of their food allocation objectives, often facing a contradictory socio-institutional environment. Three types of governance tensions, i.e. organisational, resource, and institutional, as well as the interactions among them, are analysed throughout the life-course of the GASAP network. The analysis identifies three phases in the GASAP’s life-course, showing how governance tensions and their interrelations arise and play a critical role in conditioning the overall development of the organisation through time. The paper concludes with highlighting prospective values of the hybrid governance approach for the analysis of AFNs in general. These values relate to: the role of the hybrid approach in illuminating on key drivers behind the scaling out of AFNs; the hybrid governance as a tool to conceptualise and sustain the self-reflexive capacity of local food initiatives and the ways by which this approach unravels challenges to build cooperative alliances and networks among a diversity of agents in the food arena. 相似文献
92.
Nurul Leksmono Paul Dorfman Frank Burnet David Gibbs Emma Weitkamp 《Journal of Environmental Planning and Management》2010,53(5):559-571
Schedule 11 of the Environment Act 1995 underpins the requirement for consultation on air quality issues. The ongoing air quality review and assessment process represents one of the largest locally based science policy and communication initiatives ever undertaken in the UK. This paper outlines the practice of consultation and communication for Air Quality Management (AQM) and reviews the interaction between Environmental Health professionals, as the leading actor in the AQM process and other stakeholders involved in air quality consultation, including the public. Results are presented from a widespread questionnaire survey of English local authorities. Data indicate that the majority of air quality consultation has been carried out with statutory consultees (by sending the review and assessment reports) and the public (via websites and leaflets) in the form of information dissemination. 相似文献
93.
Palaeobiological evidence indicates that gymnosperms were wind-pollinated and that insect pollination began in angiosperms in the Lower Cretaceous (ca. 135 mya) leading to close associations between higher plants and their pollinators. Cycads, which were widespread and pervasive throughout the Mesozoic (250-65 mya) are among the most primitive living seed-plants found today. Because pollination by beetles and by thrips has now been detected in several modern cycads, it is attractive to speculate that some insects and cycads had already developed similar mutualistic interactions in the Triassic (250-205 mya), long before the advent of angiosperms. We also draw attention to another key factor in this insect-plant relationship, namely secondary, defensive plant substances which must always have controlled interspecific interactions. Cycads mainly produce toxic azoglucosides and neurotoxic non-protein amino acids (e.g. BMAA), which apparently are crucial elements in the development and maintenance of mutualism (pollination) and parasitism (herbivory) by cycad-linked herbivores. We now add new results on the uptake and storage of the main toxin, cycasin, of the Mexican cycad Zamia furfuracea by its pollinator, the weevil Rhopalotria mollis, and by a specialist herbivore of Zamia integrifolia, the aposematic Atala butterfly Eumaeus atala. 相似文献
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96.
Bethwell C Müller HJ Eulenstein F Graef F 《Journal of environmental monitoring : JEM》2012,14(5):1453-1461
EU legislation stipulates that GM crops have to be monitored for potential adverse environmental effects. Monitoring preferably should take place in the most exposed areas-the cultivated fields and their neighbouring environment. Current monitoring designs do not give detailed consideration to the different exposure intensities in agricultural practice. At the same time, the selection of specific, more exposed sites is difficult considering the dynamic and diversity of crop cultivation and rotation systems and their environments. We developed an approach for prioritising the monitoring of on-farm and neighbouring sites based on differing exposure levels using a minimum dataset of cultivation and land use information. Applying a Bt-maize cultivation scenario to Brandenburg, Germany, where presently no GM crops are cultivated, we systemised and categorised areas with different spatio-temporal exposure intensities including 50 m, 200 m and 1000 m buffers. These categories correspond to different suitabilities to serve as monitoring sites. Sites are prioritised using a sequential scheme. This yields an improved and objective spatial monitoring design providing detailed exposure information. This methodology is flexible and transferable to any agricultural setting, therefore enabling superior statistical comparisons between locations and regions and thus enhancing monitoring data quality. 相似文献
97.
Gerald P. Huffman Frank E. Huggins Naresh Shah Robert Huggins William P. Linak C. Andrew Miller 《Journal of the Air & Waste Management Association (1995)》2013,63(7):1106-1114
ABSTRACT Combustion experiments were carried out on four different residual fuel oils in a 732-kW boiler. PM emission samples were separated aerodynamically by a cyclone into fractions that were nominally less than and greater than 2.5 |j.m in diameter. However, examination of several of the samples by computer-controlled scanning electron microscopy (CCSEM) revealed that part of the PM2.5 fraction consists of carbonaceous cenospheres and vesicular particles that range up to 10 |j.m in diameter. X-ray absorption fine structure (XAFS) spectroscopy data were obtained at the S, V, Ni, Fe, Cu, Zn, and As K-edges and at the Pb L-edge. Deconvolution of the X-ray absorption near edge structure (XANES) region of the S spectra established that the dominant molecular forms of S present were sulfate (26-84% of total S) and thiophene (13-39% of total S). Sulfate was greater in the PM2.5 samples than in the PM25+ samples. Inorganic sulfides and elemental sulfur were present in lower percentages. The Ni XANES spectra from all of the samples agreed fairly well with that of NiSO4, while most of the V spectra closely resembled that of vanadyl sulfate (VO?SO4?xH2O). The other metals investigated (i.e., Fe, Cu, Zn, and Pb) also were present predominantly as sulfates. Arsenic was present as an arsen-ate (As+5). X-ray diffraction patterns of the PM2.5 fraction exhibit sharp lines due to sulfate compounds (Zn, V, Ni, Ca, etc.) superimposed on broad peaks due to amorphous carbons. All of the samples contain a significant organic component, with the loss on ignition (LOI) ranging from 64 to 87% for the PM2.5 fraction and from 88 to 97% for the PM2.5+ fraction. Based on 13C nuclear magnetic resonance (NMR) analysis, the carbon is predominantly condensed in graphitic structures. Aliphatic structure was detected in only one of seven samples examined. 相似文献
98.
99.
Acute toxicity of aromatic and non-aromatic fractions of naphthenic acids extracted from oil sands process-affected water to larval zebrafish 总被引:1,自引:0,他引:1
A.G. Scarlett H.C. Reinardy T.B. Henry C.E. West R.A. Frank L.M. Hewitt S.J. Rowland 《Chemosphere》2013
The toxicity of oil sands process-affected water (OSPW) has regularly been attributed to naphthenic acids, which exist in complex mixtures. If on remediation treatment (e.g., ozonation) or on entering the environment, the mixtures of these acids all behave in the same way, then they can be studied as a whole. If, however, some acids are resistant to change, whilst others are not, or are less resistant, it is important to establish which sub-classes of acids are the most toxic. 相似文献
100.
Trends of perfluorochemicals in Greenland ringed seals and polar bears: Indications of shifts to decreasing trends 总被引:1,自引:0,他引:1
Time-series of perfluorinated alkylated substances (PFASs) in East Greenland polar bears and East and West Greenland ringed seals were updated in order to deduce whether a response to the major reduction in perfluoroalkyl production in the early 2000s had occurred. Previous studies had documented an exponential increase of perfluorooctane sulphonate (PFOS) in liver tissue from both species. In the present study, PFOS was still the far most dominant compound constituting 92% (West Greenland ringed seals), 88% (East Greenland ringed seals) and 85% (East Greenland polar bears). The PFOS concentrations increased up to 2006 with doubling times of approximately 6 years for the ringed seal populations and 14 years in case of polar bears. Since then a rapid decrease has occurred with clearing half-lives of approximately 1, 2 and 4 years, respectively. In polar bears perfluorohexane sulphonate (PFHxS) and perfluorooctane sulphonamide (PFOSA) also showed decreasing trends in recent years as do perfluorodecanoic acid (PFDA) and perfluoroundecanoic acid (PFUnA). For the West Greenland ringed seal population perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), PFDA and PFUnA peaked in the mid 2000s, whereas PFNA, PFDA and PFUnA in the East Greenland population have been stable or increasing in recent years. The peak of PFASs in Greenland ringed seals and polar bears occurred at a later time than in Canadian seals and polar bears and considerably later than observed in seal species from more southern latitudes. We suggest that this could be explained by the distance to emission hot-spots and differences in long-range transport to the Arctic. 相似文献