Food waste in municipal mixed waste produced at household level: empirical evidence from the Czech Republic

Journal of Material Cycles and Waste Management - The problem of food waste is broadly discussed, but empirical data are still missing. The importance of this topic increases as the reporting of...     

An approach for domino effect reduction based on optimal layouts

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.     

Exploring the lay/expert divide: the attribution of responsibilities for coal ash pollution in Tuzla,Bosnia and Herzegovina

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.     

Uneven distribution of urban green spaces in a coastal city in northwest Mexico

ABSTRACT

Extent 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.     

Governing climate change for a just city: challenges and lessons from Maputo,Mozambique

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.     

Landlords,fear, and children's respiratory health: an untold story of environmental injustice in the central city

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.     

The Role of Local Government in Environmental Action in Slovakia

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.     

Glass buildings on river banks as “polarized light traps” for mass-swarming polarotactic caddis flies

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.     

Why do <Emphasis Type="Italic">Manduca sexta</Emphasis> feed from white flowers? Innate and learnt colour preferences in a hawkmoth

Flower colour is an important signal used by flowering plants to attract pollinators. Many anthophilous insects have an innate colour preference that is displayed during their first foraging bouts and which could help them locate their first nectar reward. Nevertheless, learning capabilities allow insects to switch their colour preferences with experience and thus, to track variation in floral nectar availability. Manduca sexta, a crepuscular hawkmoth widely studied as a model system for sensory physiology and behaviour, visits mostly white, night-blooming flowers lacking UV reflectance throughout its range in the Americas. Nevertheless, the spectral sensitivity of the feeding behaviour of naïve moths shows a narrow peak around 450 nm wavelengths, suggesting an innate preference for the colour blue. Under more natural conditions (i.e. broader wavelength reflectance) than in previous studies, we used dual choice experiments with blue- and white-coloured feeders to investigate the innate preference of naïve moths and trained different groups to each colour to evaluate their learning capabilities. We confirmed the innate preference of M. sexta for blue and found that these moths were able to switch colour preferences after training experience. These results unequivocally demonstrate that M. sexta moths innately prefer blue when presented against white flower models and offer novel experimental evidence supporting the hypothesis that learning capabilities could be involved in their foraging preferences, including their widely observed attraction to white flowers in nature.