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681.
Antioco López-Molina Richart Vázquez-Román M. Sam Mannan M. Guadalupe Félix-Flores 《Journal of Loss Prevention in the Process Industries》2013,26(5):887-894
An approach to reduce the probability of producing a domino effect in process industry is developed in this work. It is assumed that optimal layouts should include appropriate analysis to reduce risk during the process design stage. The model developed for this approach combines the estimation of probability of damage due to overpressure, proposed by Mingguang and Juncheng (2008), and escalation threshold values defined by Cozzani, Gubinelli, and Salzano (2006). These equations are combined with other typical layout constraints as well as bounding the probability constraint, which has resulted in a highly non-linear MINLP problem. Solving a case study used by other authors provides evidence for reliability of the developed approach. In this way, layouts are designed to reduce the escalation probability yielding safe distributions. 相似文献
682.
Vanesa Castán Broto 《Local Environment》2013,18(8):879-895
Invoking expert knowledge is a common strategy in attempts to settle environmental disputes. However, the validity of expertise is contingent upon the context in which an actor is recognised as an expert. In complex environmental conflicts the distinction between lay and expert knowledge is not always fixed a priori. However, as conflicts unfold, intervening parties tend to present their cases in ways that reinforce this distinction. This is apparent in the attribution of environmental responsibilities. This paper presents an empirical case of an environmental conflict related to land contamination due to coal ash disposal in Bosnia and Herzegovina. The analysis revealed two polar positions in the conflict: the first one, mainly held by scientists and industry representatives, invoked expert knowledge and presented a distributed approach to the attribution of responsibilities; the second one, mainly held by local residents and municipal officials, presented an experiential understanding of pollution, as lay knowledge, and attributed direct responsibilities to the local energy industry. The paper concludes that the persistence of the distinction between expert and lay knowledge is a manifestation of the social structures that underlie the conflict. 相似文献
683.
Arturo Ruiz-Luna Rafael Bautista Bautista Rafael Hernández-Guzmán Vera Camacho-Valdez 《Local Environment》2013,18(5):458-472
ABSTRACTExtent and distribution of urban green spaces (UGS) in Mazatlan (Mexico) are analysed using remote sensing and GIS techniques. Vegetated areas (2,270?ha), a third of the urban area in 2015, were reclassified into green spaces (GS), urban tree (UT) and open spaces (OS), based in the normalised difference vegetation index, relating them with demographic and socioeconomic data. UGS allocation per capita amount 55?m2, mainly represented by the UT class, with the largest patches associated with low developed and very high marginalised areas, and also with very low marginalised sectors, while the lowest allocation correspond to medium and low marginalisation, highly populated sector, without significant correlations. Despite the USG allocation, it is required a better urban planning to maintain public UGS and to protect the local flora, threatened by the introduction of exotic, ornamental species (64% of UT), to guarantee the provision of ecosystem services to the population. 相似文献
684.
As new forms of governance for climate change emerge in African cities, will they enable emancipatory and socially progressive transformations or will they exacerbate existing inequality, poverty and vulnerability patterns? This paper presents one of the case studies developed by UN-Habitat Cities and Climate Change Initiative in Maputo, Mozambique. The case analyses first, the production of urban vulnerabilities under climate change, and second, the existing governance arrangements for climate change in the city. Building on the lessons of the case study, the paper argues that to ensure that new forms of climate change governance lead to socially and environmentally just outcomes climate change interventions should, at least, meet two conditions: first, they should consider the close interactions between social and ecological elements and, specially, how patterns of urban inequality interact with environmental factors; second, they should recognise the opportunities in African cities through a broad notion of governance that looks beyond the government as the sole agent of urban change. 相似文献
685.
Recent research has explored the role of environmental inequalities in explaining health disparities, especially in urban environments. This paper investigates the role of the landlord in shaping indoor environmental injustices. Specifically, we rely on interview data from low-income parents in South Phoenix, AZ, with elementary-aged children with asthma. We found families living in poor quality rental housing that impacted children's breathing. Landlords were directly involved in keeping the homes in poor condition, even when asked by the tenant to fix the property, and immigrants were especially at risk. In general, relationships between landlords and tenants were unequal and coloured by the tenant's poverty and fears of eviction. Among the immigrant tenants, many had accompanying fears of authorities and deportation. The cycle of fear, poverty, and a lack of power compounded as tenants were hesitant to report problems, which reinforced the power of the landlord over the tenant and did nothing to improve living conditions. Recognising the role of landlords in creating substandard housing conditions is important as they represent a group that can be targeted for interventions. 相似文献
686.
In the period of transition from communism, the countries of central and eastern Europe have made considerable efforts to adopt new environmental legislation and to create new institutions. However, the implementation of these powers, particularly at the level of local government, remains problematic. This article reviews the arguments for developing capacity for taking environmental action at the municipal level, and then examines the actual experience of one such country, the Slovak Republic. While Slovakia displays many of the features of policy making familiar to other transitional countries, it has faced some particular political problems. Recent legislation has given formal competencies in the field of environmental protection to local government, but it remains fragmented and relatively poorly resourced. Nevertheless, there is evidence that, through a combination of mutual support through national associations and the establishment of international links, local authorities are adopting a number of innovative approaches and strategies which should be better able to address the changing character of environmental problems. 相似文献
687.
Glass buildings on river banks as “polarized light traps” for mass-swarming polarotactic caddis flies 总被引:1,自引:1,他引:0
The caddis flies Hydropsyche pellucidula emerge at dusk from the river Danube and swarm around trees and bushes on the river bank. We document here that these aquatic insects can also be attracted en masse to the vertical glass surfaces of buildings on the river bank. The individuals lured to dark, vertical glass panes land, copulate, and remain on the glass for hours. Many of them are trapped by the partly open, tiltable windows. In laboratory choice experiments, we showed that ovipositing H. pellucidula are attracted to highly and horizontally polarized light stimulating their ventral eye region and, thus, have positive polarotaxis. In the field, we documented that highly polarizing vertical black glass surfaces are significantly more attractive to both female and male H. pellucidula than weakly polarizing white ones. Using video polarimetry, we measured the reflection-polarization characteristics of vertical glass surfaces of buildings where caddis flies swarmed. We propose that after its emergence from the river, H. pellucidula is attracted to buildings by their dark silhouettes and the glass-reflected, horizontally polarized light. After sunset, this attraction may be strengthened by positive phototaxis elicited by the buildings' lights. The novelty of this visual-ecological phenomenon is that the attraction of caddis flies to vertical glass surfaces has not been expected because vertical glass panes do not resemble the horizontal surface of waters from which these insects emerge and to which they must return to oviposit. 相似文献
688.
Ventral polarization vision in tabanids: horseflies and deerflies (Diptera: Tabanidae) are attracted to horizontally polarized light 总被引:1,自引:0,他引:1
Adult tabanid flies (horseflies and deerflies) are terrestrial and lay their eggs onto marsh plants near bodies of fresh water
because the larvae develop in water or mud. To know how tabanids locate their host animals, terrestrial rendezvous sites and
egg-laying places would be very useful for control measures against them, because the hematophagous females are primary/secondary
vectors of some severe animal/human diseases/parasites. Thus, in choice experiments performed in the field we studied the
behavior of tabanids governed by linearly polarized light. We present here evidence for positive polarotaxis, i.e., attraction
to horizontally polarized light stimulating the ventral eye region, in both males and females of 27 tabanid species. The novelty
of our findings is that positive polarotaxis has been described earlier only in connection with the water detection of some
aquatic insects ovipositing directly into water. A further particularity of our discovery is that in the order Diptera and
among blood-sucking insects the studied tabanids are the first known species possessing ventral polarization vision and definite
polarization-sensitive behavior with known functions. The polarotaxis in tabanid flies makes it possible to develop new optically
luring traps being more efficient than the existing ones based on the attraction of tabanids by the intensity and/or color
of reflected light. 相似文献
689.
The plant surface is the substrate upon which herbivorous insects and natural enemies meet and thus represents the stage for
interactions between the three trophic levels. Plant surfaces are covered by an epicuticular wax layer which is highly variable
depending on species, cultivar or plant part. Differences in wax chemistry may modulate ecological interactions. We explored
whether caterpillars of Spodoptera frugiperda, when walking over a plant surface, leave a chemical trail (kairomones) that can be detected by the parasitoid Cotesia marginiventris. Chemistry and micromorphology of cuticular waxes of two barley eceriferum wax mutants (cer-za.126, cer-yp.949) and wild-type cv. Bonus (wt) were assessed. The plants were then used to investigate potential surface effects on
the detectability of caterpillar kairomones. Here we provide evidence that C. marginiventris responds to chemical footprints of its host. Parasitoids were able to detect the kairomone on wild-type plants and on both
cer mutants but the response to cer-yp.949 (reduced wax, high aldehyde fraction) was less pronounced. Experiments with caterpillar-treated wt and mutant leaves
offered simultaneously, confirmed this observation: no difference in wasp response was found when wt was tested against cer-za.126 (reduced wax, wt-like chemical composition) but wt was significantly more attractive than cer-yp.949. This demonstrates for the first time that the wax layer can modulate the detectability of host kairomones. 相似文献
690.
Xochitl Cruz-Núñez Luis Conde Luis G. Ruiz-Suárez 《Mitigation and Adaptation Strategies for Global Change》2008,13(2):179-191
Intergovernmental Panel on Climate Change (IPCC) Tier 1 key sources level 1 assessment was applied to the 1994–1994 National
Greenhouse Gases (GHG) emission inventory for Mexico in order to identify and analyze the key sources within it. Top key sources
were from land use change and energy combustion contributing to about 60% of total national emissions. In addition, a Tier
1 trend assessment revealed some changes with respect to Tier 1 level assessment: Top key sources according to this analysis
are waste disposal and delayed emissions from land clearing. Important insight for cost effective preventive mitigation actions
can be extracted from this analysis. A comparison with other countries was carried out to find similarities in the GHG national
emissions inventories related to common features on economic development. 相似文献