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31.
Soil degradation is widely considered to be a key factor undermining agricultural livelihoods in the developing world and contributing to rural out-migration. To date, however, few quantitative studies have examined the effects of soil characteristics on human migration or other social outcomes for potentially vulnerable households. This study takes advantage of a unique longitudinal survey dataset from Kenya and Uganda containing information on household-level soil properties to investigate the effects of soil quality on population mobility. Random effects multinomial logit models are used to test for effects of soil quality on both temporary and permanent migration while accounting for a variety of potential confounders. The analysis reveals that soil quality significantly reduces migration in Kenya, particularly for temporary labor migration, but marginally increases migration in Uganda. These findings are consistent with several previous studies in showing that adverse environmental conditions tend to increase migration but not universally, contrary to common assumptions about environmentally-induced migration.  相似文献   
32.
Virtue and vulnerability: Discourses on women, gender and climate change   总被引:1,自引:0,他引:1  
In the limited literature on gender and climate change, two themes predominate - women as vulnerable or virtuous in relation to the environment. Two viewpoints become obvious: women in the South will be affected more by climate change than men in those countries and that men in the North pollute more than women. The debates are structured in specific ways in the North and the South and the discussion in the article focuses largely on examples from Sweden and India. The article traces the lineage of the arguments to the women, environment and development discussions, examining how they recur in new forms in climate debates. Questioning assumptions about women's vulnerability and virtuousness, it highlights how a focus on women's vulnerability or virtuousness can deflect attention from inequalities in decision-making. By reiterating statements about poor women in the South and the pro-environmental women of the North, these assumptions reinforce North-South biases. Generalizations about women's vulnerability and virtuousness can lead to an increase in women's responsibility without corresponding rewards. There is need to contextualise debates on climate change to enable action and to respond effectively to its adverse effects in particular places.  相似文献   
33.
This study investigates urbanization and its potential environmental consequences in Shanghai and Stockholm metropolitan areas over two decades. Changes in land use/land cover are estimated from support vector machine classifications of Landsat mosaics with grey-level co-occurrence matrix features. Landscape metrics are used to investigate changes in landscape composition and configuration and to draw preliminary conclusions about environmental impacts. Speed and magnitude of urbanization is calculated by urbanization indices and the resulting impacts on the environment are quantified by ecosystem services. Growth of urban areas and urban green spaces occurred at the expense of cropland in both regions. Alongside a decrease in natural land cover, urban areas increased by approximately 120% in Shanghai, nearly ten times as much as in Stockholm, where the most significant land cover change was a 12% urban expansion that mostly replaced agricultural areas. From the landscape metrics results, it appears that fragmentation in both study regions occurred mainly due to the growth of high density built-up areas in previously more natural/agricultural environments, while the expansion of low density built-up areas was for the most part in conjunction with pre-existing patches. Urban growth resulted in ecosystem service value losses of approximately 445 million US dollars in Shanghai, mostly due to the decrease in natural coastal wetlands while in Stockholm the value of ecosystem services changed very little. Total urban growth in Shanghai was 1768 km2 and 100 km2 in Stockholm. The developed methodology is considered a straight-forward low-cost globally applicable approach to quantitatively and qualitatively evaluate urban growth patterns that could help to address spatial, economic and ecological questions in urban and regional planning.  相似文献   
34.
Justice is an important and contested issue in the governance of fish stocks threatened by overexploitation. This study identifies the notions of justice held by stakeholders of the fishery in Newfoundland, Canada, using qualitative interviews, and interprets these notions in light of established justice theories. The interviews are analysed using inductive and deductive coding. A central result is that inshore fishers are seen as the main claim holders, with a claim to participate and be listened to, and the opportunity to make a living from the fishery. Moreover, rules play an important role in the justice notions of the interview partners, and their justice notions are clearly plural. The stakeholder notions of justice in the Newfoundland fishery resonate with the emphasis on recognition, participation and distribution as important aspects of justice within the environmental justice approach [59-61] (Schlosberg 2004, 2007, 2013).  相似文献   
35.
In this intervention article I contribute to discussions of moral economy by arguing that scholars should reconsider the nature of value. Neoliberalism considers only exchange value. As a consequence neoliberal policies try to manage problems such as climate change with economic systems and instruments that are mis-calibrated to the material realities they are meant to represent. Value has spatial and temporal characteristics. Recognizing the spatial and temporal dynamics of value leads to new means of resource valuation, such as extending the time-frame of instruments and changing the nature of privatization. In conclusion, I argue for the need for new theories of use value.  相似文献   
36.
Currently, nanotechnology has gained much interest due to the unique properties of nanomaterials in science and technology. Different types of metallic nanoparticles are routinely synthesized. However, their release into the aquatic environments is a major ecotoxicological concern. In this scenario, it is important to study the potential impact of engineered nanoparticle in aquatic organisms especially freshwater microcrustaceans, such as Ceriodaphnia cornuta. In this study, ZnO NPs were synthesized using the aqueous leaf extracts of Musa paradisiaca and physico-chemically characterized by UV–Vis spectroscopy, X-ray diffraction (XRD), Fourier transform infra red (FTIR), scanning electron microscopy (SEM) and atomic force microscopy (AFM). UV–Vis spectroscopy recorded the absorbance peak of ZnO NPs at 338 nm. XRD analysis showed the various Bragg’s reflection peaks at 100, 002, 101, 102, 110, 103, 200, 112, 201, 004 and 202 lattice planes. FTIR spectroscopy outlined sharp intense peaks at 3416 cm−1, 1388 and 1416 cm−1. SEM showed the spherical shape of ZnO NPs with mean particle size of 23.3 nm. AFM confirmed the spherical shape, nanosize and 3D topography of NPs. The ecotoxicity of ZnO NPs was tested on the freshwater crustacean C. cornuta. ZnO NPs were comparatively less toxic than zinc acetate. ZnO NPs caused 42% mortality of C. cornuta at 50 μg mL−1. However, 80% mortality was observed at 50 μg mL−1 of zinc acetate after 24 h. Light and confocal laser scanning microscopic images evidenced the uptake and accumulation of ZnO NPs in the gut of C. cornuta at 50 μg mL−1 after 24 h. Structural deformities were observed on C. cornuta after treatment with 50 μg mL−1 of ZnO NPs. Overall, this study describes the potential impact of the biologically synthesized ZnO NPs in comparison with zinc acetate in the freshwater crustacean C. cornuta.  相似文献   
37.
Where dam construction eliminates natural barriers to fish movement between previously disconnected catchments then this presents an opportunity for the movement of species between previously discrete assemblages. Here, the movement of a non-native armoured catfish, Loricariichthys platymetopon, is detailed from its natural range in the lower Paraná River basin, Brazil, into its invasive range in the upper basin following construction of the Itaipu Dam. Its upstream dispersal into a major tributary, the Paranapanema River, is outlined, with focus on its establishment within hydroelectric dams. This case study thus provides further evidence of how river regulation can increase opportunities for biological invasions.  相似文献   
38.
Understanding how science, technology and innovation can best help to accelerate progress in achieving sustainable development remains a grand challenge for researchers and practitioners. In the context of the global consultation process for preparing a post-2015 Sustainable Development Agenda, various science-based actor networks have emerged, aiming to translate research into political decision-making and to inform transformations towards sustainability. Over the last years, these networks seem to have taken an ever-growing role in structuring the science-policy interface in global sustainability governance. The question arises, however, how they understand and organize ‘scientific knowledge integration’ in sustainability politics.This study offers a structured comparison of twelve global science-based actor networks engaged in the implementation of the Sustainable Development Goals. It shows that these networks use two types of strategies to foster scientific knowledge integration in sustainability governance. A new framework emerges, in which each strategy corresponds to two main approaches of scientific knowledge integration: The entrepreneurial strategy generally seeks to advance advice-oriented and solution-oriented knowledge processes, while assessment-oriented and learning-oriented processes in scientific knowledge integration are mainly promoted through a mediating strategy.  相似文献   
39.
40.
The rhetorical zeal for green enterprise as a global fix for the tripartite challenges of economic recession, environmental degradation and social inequality is increasingly visible in state and non-state pronouncements around the globe under the banner of ‘The Green Economy’. In particular, many policy-facing statements call for transitions leading to a transformation in development practices. Yet there is little detail either in policy or research regarding the types of transitions needed and how they are to be initiated, nor agreement about what a transformed economy might look like. Despite this, there are emergent activities within the cleantech arena which are being heralded as actually existing examples of green economy activities. One means through which these activities are seeking to exert influence over development trajectories is by clustering both at the subnational and transnational level. While diverse in formation, many of these clusters are hybridised, involving actors from public, private and civil society sectors. Critiquing the efficacy of mainstream industrial cluster theory to analyse hybridised cleantech clustering, this paper presents a unique synthesis of current thought on multiscalar environmental governance and socio-spatial formations to explore the practices and potentialities of these hybridised cleantech clusters. Surveying the landscape of cleantech clustering and meta-clustering, before focusing in depth on one case study, the contribution of clustering to transitioning towards a transformed green economy is considered. Despite strong forces, both within and beyond cleantech clusters, for maintaining neoliberalised approaches to cleantech activity, it is concluded that for as long as cleantech clusters remain open and inclusive of actors proposing alternative pathways they do represent potential, albeit provisional, assemblages for transformation.  相似文献   
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