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221.
The Clean Development Mechanism (CDM) has successfully demonstrated that market-based mechanisms can achieve some cost effective emissions reductions in developing countries. However the distribution of CDM projects has been extremely uneven across countries and regions, and a few technologies and sectors have dominated the early stages of CDM experience. This has caused some to question whether the CDM has fallen short of its potential in contributing to sustainable development. We review the broad patterns of CDM project approvals and evaluate 10 CDM projects according to their sustainability benefits. The difficulty of defining “sustainable development” and the process of defining criteria by individual non-Annex 1 governments has meant that sustainable development concerns have been marginalized in some countries. Given these observed limitations, we present possible CDM policy futures, focusing on the main proposals for a post-2012 climate regime. Five options for enhancing the sustainable development benefits in the CDM are discussed, including proactive approaches to favour eligibility of emission reduction projects which ensure such co-benefits.  相似文献   
222.
Globally, norovirus is the most common gastroenteritis causing pathogen. Annually, norovirus causes 685 million cases of acute gastroenteritis and 200,000  相似文献   
223.
Based on the national database of 28,104 water rights (concessions) granted in Colombia, this paper presents an analysis of how the principles of equity and sustainability are reflected in water allocation. Concessions appear to be an exclusionary mechanism since only a minority of small water users have concessions and the distribution of water volumes among those who have them is extremely inequitable. The 2009 Gini coefficient calculated for water concessions granted for agriculture was 0.90 compared with the rural land Gini of 0.88 (both indicators grouping holdings under the same entity). More than half of the Colombian departments have a higher Gini coefficient for water than for land, suggesting that water rights are at least as unequally distributed as land, in one of the most inequitable countries in Latin America. Water allocated to domestic, agriculture and hydropower use indicates a lack of consistency of water allocation criteria across regions. The volumetric and administrative attributes of water allocation in Colombia do not account for environmental flows or the concerns of marginalised groups of society that have limited access to the mechanism. Water allocation as a technical task, with limited transparency and secluded from public scrutiny, does not contribute to the solution of increasing water-related conflicts.  相似文献   
224.
The ethnically diverse high-altitude region of Gilgit-Baltistan, with its complex political history, remains relatively free from the controlling gaze of the central state apparatus of Pakistan. In these extraordinary terrain, where local communities rule the region as the “State by proxy”, informal gemstone mining provides an important supplement to livelihoods. This paper shows that gemstone mining in Gilgit-Baltistan is characterised by customary rules and regulations that are based on collective responsibility, and members follow customary authorities because they are not external to the community. It argues that the very idea of centralised “governance” of mineral resources, used widely in contexts of resource extraction as the panacea, needs to be reconsidered when dealing with the particularities of the context. It draws on the concept of ungovernability to underline the fact that sometimes it may simply be impossible to administer informal mining in the conventional sense of the term. It suggests in conclusion that informal mining, which has a long history in Pakistan and has played an increasing role as a source of rural employment and revenue, needs to be accommodated within the legal framework of mining. More importantly, to govern informal mining of gemstones, the first task would be to consider how things are currently done, understanding and respecting customary laws, and build upon them to incorporate their elements into systems that acknowledge community rights and a more equitable sharing of benefits.  相似文献   
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Coastal social ecological systems in eastern Africa are subject to a range of environmental, social and economic changes. They are already vulnerable to these multiple stressors, and the impacts of climate change are likely to further exacerbate their vulnerabilities. Some of these impacts may be observed and experienced already. The analysis presented in this paper is based on mixed methods empirical research exploring local perceptions of recent changes at four sites in coastal Tanzania and Mozambique. People recognise and rank a number of climate and non-climate stressors which have contributed towards more risky and less diverse livelihoods. Importantly, regional and international policy initiatives – in the form of river basin management in Mozambique and South Africa, and development of a Marine Protected Area in Tanzania – are perceived to further erode resilience and exacerbate vulnerabilities. We suggest this is a form of policy misfit, where policies developed to address a specific issue do not take account of cross-scale dynamics of change, the interactions between multiple stressors, nor longer term climate change. This policy misfit may be remedied by a move towards adaptive forms of governance, and necessitates an explicit focus on building the adaptive capacity of the poor and most vulnerable in society.  相似文献   
228.
Extensive production of ethanol and vehicular use of this biofuel have recently been suggested as possible sources of elevated volatile organic carbon (VOC) in rain in Brazil (Campos, M.L.A.M., Nogueira, R.F.P., Dametto, P.R., Francisco, J.G., Coelho, C.H., 2007. Dissolved organic carbon in rainwater: glassware decontamination and sample preservation and volatile organic carbon. Atmos. Environ. 41, 8924–8931; Coelho, C.H., Francisco, J.G., Nogueira, R.F.P., Campos, M.L.A.M., 2008. Dissolved organic carbon in rainwater from areas heavily impacted by sugar cane burning. Atmos. Environ. 42, 7115–7121). Furthermore, these studies suggested that the global flux of rainwater dissolved organic carbon (DOC) may be underestimated since most DOC analytical methods do not measure VOC. The current study examined rain VOC in Wilmington, North Carolina USA in order to assess the importance of rain VOC in a location that does not have the unique conditions of ethanol production and usage found in Brazil. VOC was observed in one of six whole rain events analyzed in the current study. This event had an air mass back trajectory that originated over the Midwestern USA, the primary region where ethanol is produced and used as fuel. The other five storms which had no influence from the central US prior to arrival at the rain collection site had non-detectable VOC suggesting that air mass back trajectory has a dramatic impact on the VOC content of rainwater. VOC was also observed in the initial 1 mm of rain from two of these events but was not detectable in the whole event samples suggesting VOC is efficiently washed out of the atmosphere and is not rapidly resupplied in rainwater at this location. Considering the results of the previous Brazilian studies and the current study, and the likelihood of increased global production and consumption of ethanol based biofuels, it is imperative that future measurements of rainwater DOC include measurement of VOC. Monitoring changes in the VOC contribution to rain DOC will provide an assessment of the impact of increased ethanol biofuel usage on rainwater composition and allow for future refinements of global rainwater DOC flux estimates.  相似文献   
229.
We used boosted regression trees (BRT) to model stream biological condition as measured by benthic macroinvertebrate taxonomic completeness, the ratio of observed to expected (O/E) taxa. Models were developed with and without exclusion of rare taxa at a site. BRT models are robust, requiring few assumptions compared with traditional modeling techniques such as multiple linear regression. The BRT models were constructed to provide baseline support to stressor delineation by identifying natural physiographic and human land use gradients affecting stream biological condition statewide and for eight ecological regions within the state, as part of the development of numerical biological objectives for California’s wadeable streams. Regions were defined on the basis of ecological, hydrologic, and jurisdictional factors and roughly corresponded with ecoregions. Physiographic and land use variables were derived from geographic information system coverages. The model for the entire state (n?=?1,386) identified a composite measure of anthropogenic disturbance (the sum of urban, agricultural, and unmanaged roadside vegetation land cover) within the local watershed as the most important variable, explaining 56 % of the variance in O/E values. Models for individual regions explained between 51 and 84 % of the variance in O/E values. Measures of human disturbance were important in the three coastal regions. In the South Coast and Coastal Chaparral, local watershed measures of urbanization were the most important variables related to biological condition, while in the North Coast the composite measure of human disturbance at the watershed scale was most important. In the two mountain regions, natural gradients were most important, including slope, precipitation, and temperature. The remaining three regions had relatively small sample sizes (n?≤?75 sites) and had models that gave mixed results. Understanding the spatial scale at which land use and land cover affect taxonomic completeness is imperative for sound management. Our results suggest that invertebrate taxonomic completeness is affected by human disturbance at the statewide and regional levels, with some differences among regions in the importance of natural gradients and types of human disturbance. The construction and application of models similar to the ones presented here could be useful in the planning and prioritization of actions for protection and conservation of biodiversity in California streams.  相似文献   
230.
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