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711.
The REDD-ALERT (Reducing Emissions from Deforestation and Degradation from Alternative Land Uses in the Rainforests of the Tropics) project started in 2009 and finished in 2012, and had the aim of evaluating mechanisms that translate international-level agreements into instruments that would help change the behaviour of land users while minimising adverse repercussions on their livelihoods. Findings showed that some developing tropical countries have recently been through a forest transition, thus shifting from declining to expanding forests at a national scale. However, in most of these (e.g. Vietnam), a significant part of the recent increase in national forest cover is associated with an increase in importation of food and timber products from abroad, representing leakage of carbon stocks across international borders. Avoiding deforestation and restoring forests will require a mixture of regulatory approaches, emerging market-based instruments, suasive options, and hybrid management measures. Policy analysis and modelling work showed the high degree of complexity at local levels and highlighted the need to take this heterogeneity into account—it is unlikely that there will be a one size fits all approach to make Reducing Emissions from Deforestation and Degradation (REDD+) work. Significant progress was made in the quantification of carbon and greenhouse gas (GHG) fluxes following land-use change in the tropics, contributing to narrower confidence intervals on peat-based emissions and their reporting standards. There are indications that there is only a short and relatively small window of opportunity of making REDD+ work—these included the fact that forest-related emissions as a fraction of total global GHG emissions have been decreasing over time due to the increase in fossil fuel emissions, and that the cost efficiency of REDD+ may be much less than originally thought due to the need to factor in safeguard costs, transaction costs and monitoring costs. Nevertheless, REDD+ has raised global awareness of the world’s forests and the factors affecting them, and future developments should contribute to the emergence of new landscape-based approaches to protecting a wider range of ecosystem services.  相似文献   
712.
The phylogeny of Collembola, originally discussed from a morphological point of view, has more recently benefited from novel insights brought by molecular analyses. Both morphological and molecular characters produced a well-resolved phylogenetic hypothesis including all orders, most families, and a large number of genera. However, several conflicting points exist between molecular and morphological data, and new characters are clearly needed to resolve these inconsistencies. In this study the usefulness of a new character type not previously used in the phylogenetic study of Collembola was tested: the epicuticular chemical compounds. Our phylogenetic analysis was based on 380 compounds from 26 Collembola species. The results show good resolution for terminal branches but not for internal nodes. This is probably due to the partial involvement of epicuticular lipids in ecological functions such as water conservation and sexual attraction. Thus, this character type is appropriate for reconstructing phylogenetic relationships among recently diversified groups. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
713.
Bird abundance was assessed on a total of 58 farms across the Seine-et-Marne department, France (12 organic, 19 conservation-tillage and 27 conventional farms). Local abundance variations among the three farming systems were related to two species traits, i.e. habitat specialisation and diet, considering both farmland and non-farmland species. It was found that organic farming favoured specialist birds, either considering the whole community or non-farmland birds only. On the opposite, specialist farmland species were found to be less abundant in conservation-tillage farms than in conventional ones. Invertebrate-feeders were found to benefit from conservation-tillage practices compared to omnivorous species but not compared to granivorous ones; an interaction between species diet and the species specialisation level was also found. Granivorous species tended to increase with the conservation-tillage duration and in particular specialist birds.  相似文献   
714.
Global sustainability is increasingly influenced by processes of industrialisation and urbanization in non-OECD countries, especially in Asia. Growth models suggest that developing economies and regions will become first relatively more resource- and pollution-intensive, before converging on more resource-efficient and low-pollution production and consumption patterns expressed in developed countries. Alternative less resource- and pollution-intensive growth models for latecomer countries promise social and economic benefits in the short- and long-term. Drawing on insights from system innovation research on long-run change in socio-technical systems, we discuss the potential role of ‘sustainability experiments’ to generate innovations that will constitute new ‘greener’ growth models. We observe a great number of technology-based initiatives that we characterize as sustainability experiments in East and South Asian countries. These experiments emerge in the context of the growth of new socio-technical regimes in key sectors, including energy, transport, manufacturing, food and the built environment. We set out a conceptual framework for assessing the role of experiments, and for evaluating how they link with and become anchored into alternative more sustainable regimes. In this paper we argue that sustainability experiments represent a significant new source of innovation and capability-formation, linked to global knowledge and technology flows, which could reshape emergent socio-technical regimes and so contribute to alternative development pathways in latecomer countries. We conclude by summarizing the six papers published in this Special Issue.  相似文献   
715.
INTRODUCTION: This article examines five major road-safety risk factors: exceeding posted speed limits, not using safety belts, driving while intoxicated, nighttime driving, and young drivers. METHOD: The importance of each of these factors is documented, known effective countermeasures (both policy and technology based) are discussed, and impediments to the implementation of these countermeasures in the United States are examined. RESULTS: Based on current understanding of the five major risk factors, and of the available countermeasures, there appear to be a variety of opportunities to make substantial gains in road safety using existing knowledge. The limited implementation of a variety of known countermeasures therefore appears to be inconsistent with high-level, strategic goals to improve road safety. Consequently, a recommendation is made to comprehensively re-examine the balance between the countermeasures discussed in this article and economic, mobility, and privacy concerns. IMPACT ON PUBLIC SAFETY: Such a re-examination is likely to result in broad support for these countermeasures, with a consequent major improvement in road safety.  相似文献   
716.
Social capacity building for natural hazards is a topic increasingly gaining relevance not only for so-called developing countries but also for European welfare states which are continuously challenged by the social, economic and ecological impacts of natural hazards. Following an outline of recent governance changes with regard to natural hazards, we develop a heuristic model of social capacity building by taking into account a wide range of existing expertise from different fields of research. Particular attention is paid to social vulnerability and its assessment, as well as to risk communication and risk education as specific strategies of social capacity building. We propose to distinguish between interventionist and participatory approaches, thus enabling for a better understanding of existing practices of social capacity building as well as their particular strengths and weaknesses. By way of conclusion, we encourage more research on social capacity building for natural hazards in the European context which at present is highly diverse and, at least in parts, only poorly investigated.  相似文献   
717.
718.
Environmental Science and Pollution Research - The chemical contaminants in dried fish are of great food safety concern and an emerging public health issue in Bangladesh. The aim of this study was...  相似文献   
719.
添加生物炭对西北黄土吸附克百威的影响   总被引:3,自引:1,他引:3  
研究了不同温度下制得的生物炭对西北黄土吸附农药克百威的影响,并对溶液p H值和初始浓度对吸附的影响进行了探讨.结果表明,克百威在添加生物炭黄土上的动力学吸附过程较好地符合准二级吸附动力学模型;热力学吸附较好地符合Freundlich等温吸附模型;随着系统温度的升高,添加生物炭的黄土对克百威的吸附量增大,且其对克百威的吸附自由能变(ΔGθ)小于0,吸附焓变(ΔHθ)及吸附熵变(ΔSθ)均大于0,表明吸附是一个自发吸热且体系混乱程度增大的等温吸附过程.溶液p H值和克百威的初始浓度对添加生物炭的土样吸附影响较明显.当p H值为4~7时,添加生物炭的土样饱和吸附量随p H升高呈缓慢降低,当p H值大于7时,吸附容量随p H升高呈明显降低趋势.克百威初始浓度从20 mg·L-1增至50 mg·L-1的过程中,吸附量快速上升,初始浓度大于50 mg·L-1时,吸附量随初始浓度的升高而缓慢增加并逐渐趋于平衡.  相似文献   
720.
Environment, Development and Sustainability - The Economic Community of West African States has keyed into the various international agreements that seek to protect the environment and reduce...  相似文献   
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