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111.
As the biggest inter-basin water transfer scheme in the world,the South-to-North Water Diversion Project(SNWD) was designed to alleviate the water crisis in North China.The main channel of the middle route of the SNWD is of great concern in terms of the drinking water quality.In this study,we tested the hypothesis that the dissolved organic matter(DOM) derived from the planktonic algae causes the rising levels of CODMn along the middle route by monitoring data on water quality(2015-20...  相似文献   
112.
Abstract

A number of cities around the world are associated with very high levels of private motor car usage, and Auckland provides an example of one of these ‘hyperautomobile’ cities. There are many problems with this system of transportation and dependence on the private car, including environmental, social and city design dimensions. Though there is a clear aspiration to move towards reduced levels of car usage in the city's transport and spatial planning strategies, there are major difficulties in implementation terms. We develop and consider future scenarios to 2041 to reduce these levels of motorization, and subsequent transport CO2 emissions, with a much greater use of public transport, walking and cycling, urban planning, and low emission vehicles. The current implementability of such a ‘sustainable mobility’ future is however questioned in the current political and social context, and critically debated in terms of the available governance mechanisms and the limited attempts to shape the behaviour of the public. We conclude by calling for a reconsideration of the policy measures being considered, including the range and levels of application and investment; with a much wider framing of the transport planning remit, and carried out within a much stronger participatory framework for decision-making.  相似文献   
113.
This study examines ten programmes to advance energy efficiency and retrofitting of existing, private sector buildings in C40 cities in Asia-Pacific and USA. We set out to identify differing policy approaches, together with potential impacts and implementation challenges for each. Findings unearthed six policy models – both mandatory and voluntary – with unique impacts and challenges. We demonstrate that innovation occurs without new policy inventions and largely by necessity, as new features are added and generic models are adapted to local circumstances. Our sample demonstrated experimentation with benchmarking in the USA, comprehensive regulation in Asia, and voluntary approaches in Australia. Overall, environmental impacts are particularly slow to emerge and plagued with attribution challenges. We found limited evidence of benchmarking programme effectiveness in reducing energy consumption in the short-term, but some indication of mid-term outcomes. Driven by unique local circumstances, the cap-and-trade model stood out by fostering large, sustained and attributable GHG emission reductions and retrofitting. Market and social impacts are highly significant across all programmes, highlighting needs to consider non-environmental impacts in policy evaluation. We emphasise the complementary potential of voluntary and regulatory approaches to advancing energy efficiency and climate resilience. We also underscore the potential for reporting or benchmarking programmes to later transition to models mandating performance improvements, such as cap-and-trade.  相似文献   
114.
国家统计局数据显示,2006年我国节能减排任务均远未实现国家"十一五"规划开局之年的目标,特别是主要污染物排放总量不降反升.本文在分析了中国环境治理体系和国家"十一五"规划主要污染物减排指标分配机制的基础上,研究了市场转型对中国环境治理结构的影响.中国的市场转型可以抽象为以"分权让利"、"市场化"和"工业化"为主要特征的结构演进过程.文中提出,中国市场转型过程对环境治理结构造成了重大影响,而环境治理的各项措施反过来也应与市场转型相适应.当前中国主要污染物减排指标没有实现达标的重要原因是国家污染物减排指标的分配机制无法适应我国市场转型的要求.为此,本文提出一系列国家主要污染物减排指标分配机制的政策建议.  相似文献   
115.
为了解不同植被类型土壤水资源的变化规律,选择南水北调中线水源区宁陕县寨沟区域典型植被针阔混交林、针叶林、板栗林、灌木林、荒坡草地和坡耕地为研究对象,通过样地调查与实验分析的方法对其土壤水分物理特征及有机质含量进行测定研究。结果表明,各种有林地的土壤容重、孔隙度和有机质等理化特征均优于荒坡和坡耕地;针阔混交林土壤含水量最高,蓄水能力明显好于其它植被类型;在垂直剖面上,各种植被类型坡地土壤含水量和饱和蓄水量随土壤深度的增加基本呈递减趋势,但有林地下降幅度较大,表层含水量明显高于荒坡与坡耕地表层。由此可见,在涵养水源方面,针阔混交林最好,针叶林、板栗林与灌木林次之,荒坡与坡耕地较差。  相似文献   
116.
This paper examines the connections among sustainability, governance and GDP, using the data from 123 countries. Sustainability is found to be related with GDP in two contradictory ways. On the one hand, growth in GDP strengthens a nation's ability to maintain favorable environmental conditions into the future. On the other hand, GDP growth is built on more consumption of natural resources, and therefore generates a larger "foot-print" on the Earth. Governance plays a key role in sustainable development. However, it is not helping to reduce our footprint on the Earth. In fact, good governance is linked to a larger footprint. This reflects our materialist value and human impulse. When a society prefers the comfort and wellbeing of human beings to the welfare of its environment, democratic governance might be used as an effective tool against nature.  相似文献   
117.
水质安全是调水工程顺利实施的关键,为此调水区背负巨大的调水工程的外部经济成本和社会发展代价,必须通过生态补偿政策进行内部化,然而调水工程涉及的范围广、时间长、利益主体多、资金投入大,难以通过一种手段或者现有某种方式建立长效的生态补偿机制。文章从调水工程生态补偿政策建立的目标、标准、责任分担与利益共享、补偿方式角度分析了生态补偿现状及存在的问题,提出了调水工程生态补偿的分阶段推进战略总体思路与实施构想,重点分析了各阶段生态补偿政策的制定标准和要求,为中线调水工程生态补偿政策制定提供了技术支持。  相似文献   
118.
The levels of greenhouse gases in the atmosphere keep increasing every year, and despite the adoption of the Paris agreement, one cannot expect any significant dip in the trend in the near future. We may therefore legitimately question the efficiency of the current governance system, notably concerning the interplay between science and policy. The strategy adopted by the UNFCCC in Paris contrasts with the strategy adopted in Kyoto, as it endorses a dynamic that is more bottom-up. Its success will depend greatly on the ability of the actors to mobilise on climate issues and to find ways to work together. Scientific expertise has a key role to play to this respect. This paper is a reflection led by the French Association for Disaster Risk Reduction on how the Intergovernmental Panel on Climate Change could evolve in order to usefully accompany that strategy. Introducing more reflexivity in the assessment process and widening aspects of the expertise to a more diverse and transdisciplinary range of actors could improve the treatment of uncertainties, multi-scale interactions and the appropriation of expertise, as well as the integration of adaptation and mitigation policies. In practical terms, this could involve more working groups, which could become more focused, drawing up shorter but more frequent reports, and taking account of the “grey” expert literature. The implementation of such an approach merits further investigation, because these improvements could help address the governance challenges in climate change.  相似文献   
119.
The concept of participation in rural development has been evolutionary for the past two decades with those involved, such as development agencies and governments, particularly in rural water supply, re-evaluating their active role. The move towards effective community participation has encouraged a shift from the traditional top-down to a bottom-up approach whereby there is a decentralisation of unevenly distributed resources and power to empower a community and allow mobility of ‘people participation’. The Molinos water project is the first large-scale development project of its kind introduced into the village of Molinos in an under-developed area of Chile, where there has been no tradition of people participation. The project objective was to implement a low technology, low budget water treatment plant to the village of Molinos. Various aspects have hindered the continued development of the project including both technical and financial. In terms of people participation, the initial approach used was the top-down approach. There was a failure to fully integrate the community or inform the community in a formal manner about the project and consult them regarding key project issues. This case study illustrates that the lack of comprehensive consultation and the low level of participation of the community on the participatory scale does not achieve much in terms of people-centred benefits. For governance at the local level to be effective, participation should be inclusive and communicative so as to enhance transparency throughout the project lifetime. Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.  相似文献   
120.
Climate variability and population growth have intensified the search internationally for measures to adapt to fluctuations in water supplies. An example can be found in the lower part of the transboundary Tigris‐Euphrates Basin where water shortages in 2008‐2009 resulted in high economic costs to irrigation farmers. Losses to irrigators in the lower basin have made a compelling case to identify flexible methods to adapt to water shortage. Few published studies have systematically examined ways to enhance the flexibility of water appropriation systems to adapt to water shortage. This article addresses an ongoing challenge in water governance by examining how profitability at both the farm and basin levels is affected by various water appropriation systems. Four water appropriation systems are compared for impacts on farm income under each of three water supply scenarios. Results show that a (1) proportional sharing of water shortages among provinces and (2) unrestricted water trading rank as the top two appropriation systems. The shadow price of water for irrigation rises from zero at a full water supply level to US$93/1,000 m3 when supply falls to 20% of full levels. Similar methods could be used to analyze challenges facing the design or implementation of water appropriation systems in the world's irrigated regions.  相似文献   
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