The urban political ecology of plastic bag waste problem in Nairobi, Kenya

Over 24 million plastic bags are consumed in Kenya monthly. More than half of the bags end up in the solid waste stream. Plastic bags now constitute the biggest challenge to solid waste management in Nairobi, the capital of Kenya and home to three million people. As a result, plastic bag waste has attracted great political and public attention, especially because the waste has myriad unique environmental problems. This paper seeks to unravel the problem of plastic bag waste in Nairobi through an urban political ecological perspective. Urban political ecology has done much to excavate economic, political, and cultural processes, as well as ecological dynamics that create and re-create urban environments. Little has been done in this context with respect to urban solid waste problems, with the exception of urban political ecology of environmental justice. However, research done within the context of urban political ecology of environmental justice has mainly focused on solid waste problems in the Western World, particularly USA. Drawing on research conducted in Nairobi, as well literature on business and politics, and solid waste management in Kenya, this paper examines the nature of plastic bag waste problem, its political–economic roots and implications for environmental justice.     

The “battle of gold” under the light of green economics: a case study from Greece

Mining firms stimulate local and national economies but this comes at a certain cost. In the light of increasing public concern, external costs of environmental degradation and social disruption are no longer of pure academic interest. The assessment of mining projects on the grounds of sustainable development is critical in order to decide whether the exploitation of mineral resources is socially desirable. In practice, few steps have been taken towards this end. In this paper, a case study is illustrated that provides the means for evaluating the social worthiness of mining projects. The analysis, which is the first of its kind in Greece, deals with a major problem of the mining industry: the gold debate on the grounds of green economics. The assessment is based on the social cost–benefit approach. Well-established techniques (e.g. benefit transfer) and innovative approaches have been adopted to overcome various practical problems     

Contesting sustainable development in Tierra del Fuego

Despite wide ranging interpretations of the concept of sustainable development there is growing consensus about the ecological, social, and economic conditions necessary to foster a sustainability transition. In addition to quantitative assessments of sustainability indicators, qualitative process indicators are being identified. For example, active, democratic, and inclusive decision-making are shown to lead to more informed decisions and, presumably, more sustainable use systems. The creation of these conditions, however, often requires bridging lack of mutual trust and scientific uncertainty. And while the ideals of sustainable development suggest that all stakeholders get what they want, without compromise nothing approaching sustainable development is attainable. Obstructing compromise, environmental ideology represents a key remaining hurdle to achieving a middle ground in environment and development debates. In the 1990s, the US-based Trillium Corporation sought to implement a large-scale logging project in Tierra del Fuego, Chile, but was rebuffed by environmentalists who embraced ecotourism as the preferred development option. The case is analyzed in the context of calls to reconsider conceptually nature-society relationships and ideas in sustainability science about which land management systems best match sustainability goals. Findings show that the decision-making process for determining whether or not to implement the logging project was flawed. We explore two implications. First, achieving sustainable development requires a consensus view of nature-society relationships that embraces humanized landscapes. Second, inclusive and effective decision-making about sustainable development necessitates free and open exchange of information, collective learning about regional environment and development, and the identification of compromise positions.     

Partitioning of elements and macerals during preparation of Antaibao coal

Analyses of the macerals, ash, sulfur and 43 major and trace elements were performed on samples of feed coal, cleaned coal, middlings and slime collected from the Antaibao coal preparation plant, China, and also on samples from coal preparation experiments. This study is focused on the partitioning of elements and macerals during coal preparation and potential environment aspects of the elements.The conclusions are as follows: (1) in comparison with the feed coal, the cleaned coal has a higher vitrinite content and relatively lower inertinite and exinite contents, whereas the middlings and slime have lower vitrinite and exinite contents, and relatively higher inertinite contents. The vitrinite contents in the size-segregated cleaned coals were observed to show a slightly increasing tendency with increasing particle size, while the inertinite contents decreased. (2) Physical coal cleaning is not only effective for removal of ash and sulfur, but also in reducing the concentration of most elements. As, Cd, Co, Cs, Hg, Fe, K, Mg, Nb and Ni are observed to show a high degree of removal, while Br, Be, Cu, U, Mn, Zn and organic sulfur are enriched in the cleaned coal and show a lower degree of removal. The large-sized cleaned coal is cleaner than the smaller sized fractions. (3) The middlings, especially the slime, are enriched in S, Hg, Cr, V, Zn, etc., so that these fractions should not be directly used as fuel. In addition, the concentration of Pb and V in the process water exceeds the limit of relevant environmental water quality standard. Consequently, it is necessary to develop new processes to remove ash, sulfur and hazardous trace elements to the maximum extent. Further studies on deep processing of the middlings and slime and cleaning of the process water should also be performed.     

Postcolonial environmental justice: Government and governance in India

In this paper, we investigate the context within which struggles for environmental justice are taking place in India. We explore the ways in which postcolonial patterns of government and governance in India affect the ends, the means and the representation of these struggles, focusing on three particular areas: state reform, the judiciary and public interest litigation, and environmental social movements. We argue that India differs from west in the ambitious yet incomplete and contradictory nature of government-sponsored intervention in the environment, and in the particular nature of its public sphere, both of which have been important in shaping struggles for environmental justice. Our wider intention is not merely to catalogue these differences, but to use the Indian material to raise questions about the emphases and implicit assumptions of western environmental justice literature, and reflect on how these may be need reconsideration when working in postcolonial contexts.     

Enacting environmental justice in Singapore: Performative justice and the Green Volunteer Network

Environmental justice research has of late expanded beyond its’ original focus on the distribution of environmental ‘bads’ to debate injustices at a wide array of sites and scales. Despite this expansion, the applicability of an environmental justice framework to seemingly apolitical and banal expressions of environmental concerns remains open to question. This paper argues that environmental justice struggles can be located in the mundane environmental politics of Singapore, by employing a performative rather than rights-based approach to both justice and politics. It draws on qualitative research into volunteers’ practices in one Singaporean environmental organisation, and asserts that through their focus on experiential learning and re-inscribing ‘developmental’ spaces as spaces of care and justice, volunteers seek to redress the social, political and environmental injustices replete within the spatial politics of Singapore.     

环境同位素技术在水源地勘探中的应用——以河北姜泡水源地为例

本文以采样和测试取得的第一性资料为依据，配合水源地勘察和群孔抽水试验开展河北滦南姜泡水源地第四系含水层同位素水文地质研究，查明天然和开采状态下地下水环境同位素丰度及其变化规律性，结果表明Ⅰ、Ⅱ含水层地下水与河水存在水力联系，是近代渗入成因水。主勘探层Ⅲ含水层与河水无联系，是不同年代形成的古渗入成因水，以侧向迳流补给为主，补给区位于研究区的东部。该层地下水由NE朝SW，后折向正南方向流动，速率为1—1．5m/a。含水层组地下水的贮留时间距今2300．15700a，Ⅲ2的贮留时间距今5800—23200a，地下水pH为7．2—8．3、溶解固体量小于300mg／L、水质较好的淡水，具有开发应用前景。     

烧失量分析在湖泊沉积与环境变化研究中的应用

烧失量分析是一种便捷的测定湖泊沉积物有机碳与碳酸盐含量的方法。由于沉积物烧失量主要受区域气温、有效降水等气候环境条件的控制,因此烧失量反映湖泊气候环境特征,成为指示区域气候环境变化的重要指标,该项指标在环境变化研究中具有重要作用。     

Selection of prior distributions and multiscale analysis in Bayesian temperature reconstructions based on fossil assemblages

It is possible to reconstruct the past variation of an environmental variable from measured historical indicators when the modern values of the variable and the indicators are known. In a Bayesian statistical approach, the selection of a prior probability distribution for the past values of the environmental variable can then be crucial and the selection therefore should be made carefully. This is particularly the case when the data are noisy and the statistical model used is complex since the influence of the prior on the results can then be especially strong. It can be difficult to elicit the prior probability distribution from the available information, since usually there are no measured data on the past values of the variable one wants to reconstruct and different reconstructions are typically consistent with each other only at a coarse level. To overcome these difficulties we propose to use a non-informative smoothing prior, possibly in combination with an informative prior, that simply penalizes for roughness of the reconstruction as measured by the variability of its values. We believe that it can sometimes be easier to set an overall prior distribution on the roughness than to agree on a prior for the actual values of the reconstructed variable. Note that by using a smoothing prior one incorporates into the model itself the smoothing step usually done before or after the actual numerical reconstruction. Another idea proposed in this paper is to integrate the reconstruction model with a multiscale feature analysis technique known as SiZer. Multiscale analysis of the posterior distribution of the reconstructed variable makes it possible to infer its statistically significant features such as trends, maxima and minima at several different time scales. While only temperature is considered in this paper, the technique can be applied to other environmental variables.     

A framework for dealing with uncertainty due to model structure error

Although uncertainty about structures of environmental models (conceptual uncertainty) is often acknowledged to be the main source of uncertainty in model predictions, it is rarely considered in environmental modelling. Rather, formal uncertainty analyses have traditionally focused on model parameters and input data as the principal source of uncertainty in model predictions. The traditional approach to model uncertainty analysis, which considers only a single conceptual model, may fail to adequately sample the relevant space of plausible conceptual models. As such, it is prone to modelling bias and underestimation of predictive uncertainty.