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951.
Jordanian authorities have achieved a nearly one hundred percent connection rate to municipal water supply services in urban areas. Following this unusual achievement for a lower-income country, a private management contractor was introduced to the capital city Amman, along with a form of economic regulation. However, water rationing due to extreme water scarcity, amplified by high and irregular population growth, disproportionately affects the city’s low-income households. This paper investigates the status of water supply service and regulatory arrangements with respect to poor and vulnerable consumers who were targeted in a household survey in June/July 2005. It identifies specific regulatory challenges which were not within the remit of or addressed by the acting quasi-regulator and the water authorities. In its extremes of connection coverage, water scarcity and population, the management of water supply in Amman presages the pro-poor water service challenge of many, even lower income, economies irrespective of the extent to which they may achieve the access targets of the Millennium Development Goals.  相似文献   
952.
Use of microtremor in liquefaction hazard mapping   总被引:1,自引:0,他引:1  
This study shows how microtremor measurements can be used as an aid to liquefaction hazard mapping and zonation, as demonstrated in Laoag City, Northern Philippines. From microtremor measurements, qualitative information on subsoil conditions was obtained and a site classification map was generated. The map was combined with the geomorphology-based liquefaction susceptibility map to produce an integrated liquefaction hazard zonation map. This integrated map is deemed to be more accurate in depicting relative liquefaction susceptibility since it combines information on the distribution of potentially liquefiable soils in terms of geology and grain characteristics with information on the stiffness and thickness of these soils. With information about the thickness of the deposits, an idea of the severity of liquefaction-related damage can also be gathered since thicker deposits relate to more serious damage. Plots of historical liquefaction cases, as well as borehole data and resistivity profiles in the study area, support the validity of the integrated map. The use of microtremor, therefore, constitutes an effective and inexpensive approach to liquefaction hazard zonation, and as such is very useful in less-developed countries like the Philippines and other areas where funds for more rigorous investigations are not always available.  相似文献   
953.
导航数据库(Navigable Database)是指针对智能交通系统与定位服务应用需求而建立的具有统一技术标准的地理数据库.本文对导航数据与一般的地理信息数据在数据模型、数据的准确性、数据的组织方法等方面进行了比较.在简要介绍导航数据库概念后,讨论了城市交通系统中导航数据的来源及导航数据的处理理论.  相似文献   
954.
基于RS、GIS、景观生态学等方法,以新疆典型干旱区轮台县为研究区,利用1997年、2007年、2017年三期遥感影像解译结果,定量分析轮台县20年间土地利用景观格局变化特征,并运用生态系统服务价值(ESV)估算原理,定量分析轮台县生态服务功能ESV的年际变化,探讨ESV在景观格局演变下的损益和响应,来反映生态输水对塔河沿岸生态的影响。结果表明:轮台县以未利用地大幅度减少,林地与草地的大量增加为主,同时耕地、水域、建设用地以及冰川的面积也有不同程度的增加,但相对于整个县域面积依然相对较小;各斑块类型景观格局指数和整体景观格局指数以及空间格局都发生了不同程度的变化,未利用地对景观整体的控制性减弱,土地利用均匀性和多样性增加,最大斑块指数变化显著,散布并列指数先略有下降后明显增加;轮台县20年间各项生态系统服务功能的ESV均呈显著增加的趋势,ESV总量不断增大;轮台县ESV的增益集中在林地的增加上,占总增益的65.9%,轮台县ESV的损益集中在建设用地和未利用地的转入上,说明林地的增加和未利用地的减少是轮台县ESV增加的主要原因。该研究体现典型水源灌溉对轮台县生态的影响,为干旱区生态系统改善和土地利用规划提供依据。  相似文献   
955.
填海造陆已经成为全球沿海地区缓解土地短缺、促进社会发展和经济增长的重要手段。随着快速工业化和城市化过程,亚洲已经成为填海造陆的中心。从天津滨海新区到唐山曹妃甸新区,在渤海西北岸正在进行的填海工程其规模在世界上名列前茅。为了剖析海岸带发展的环境因素并促进其可持续发展,对渤海西北岸填海造陆的生态损失采取了回顾性和预测性评价,从生态系统服务角度货币化计算了供给、调节、支持、文化四大类10个方面的生态损失。结果表明:2000-2010年填海造陆的生态损失为9.719亿美元,2010-2020年新增填海造陆的生态损失将达7.021亿美元,其中气体调节和水产品供应方面的损失最大。针对填海造陆可持续发展,提出相关建议,包括:在综合评估基础上的合理规划;减少填海造陆面积;优化填海区土地结构;采用“低影响”开发模式填海;采用生态补偿机制,等。  相似文献   
956.
New multi-sectoral policies with a regional implementation are developed when maritime states recognise the importance of managing the marine environment under an ecosystem-perspective rather than a use-perspective. In Europe, the Marine Strategy Framework Directive (MSFD) is the first attempt to promote an integrated management of the seas from the coastline to the limit of the Exclusive Economic Zone. This paper shows that, nine years from the MSFD adoption, there remain several ecological, economic, social and governance challenges. Using information gathered in a dedicated survey of the European Union Marine Strategy Coordination Group and in the recent literature the paper identifies the obstacles preventing a successful regional cooperation and policy integration. The survey indicates that the MSFD coordination structures are, in general, well-developed but there is an apparent lack of political will to coordinate actions at the regional level. Member States request greater flexibility to implement the Directive but they put their national interests before the benefit of a coherent and integrated approach for the entire region. Differences in budget, economic sector predominance, lack of staff and the MSFD short time-scale are identified as the factors that can hamper cooperation. These have produced recommendations of possible strategies for optimising regional coordination structures which respect the subsidiarity principle underpinning the MSFD.  相似文献   
957.
Growing coastal populations, rising sea levels, and likely increases in the frequency of major storm events will intensify coastal vulnerability in coming decades. Decisions regarding how and when to fortify estuarine shorelines against coastal hazards, such as erosion, flooding, and attendant property damages, rest largely in the hands of waterfront-property owners. Traditionally, hard engineered structures (e.g. bulkheads, revetments, seawalls) have been used to protect coastal properties, based on the assumption that these structures are durable and effective at preventing erosion. This study evaluates the validity of these assumptions by merging results from 689 surveys of waterfront-property owners in NC with empirical shoreline damage data collected along estuarine shorelines after Hurricanes Irene (2011) and Arthur (2014). The data show: 1) homeowners perceive bulkheads to be the most durable and effective at preventing erosion, but also the most costly; 2) compared to residents with revetments and natural shorelines, property owners with bulkheads reported double the price to repair hurricane damage to their property and four times the cost for annual shoreline maintenance; 3) 93% of evident post-hurricane shoreline damage was attributable to bulkheads or bulkhead hybrids and a higher proportion of surveyed homeowners with bulkheads reported having property damage from hurricanes; and, 4) shoreline hardening increased by 3.5% from 2011 to 2016 along 39 km of the Outer Banks. These results suggest that bulkheads are not meeting waterfront property-owner expectations despite continued use, and that nature-based coastal protection schemes may be able to more effectively align with homeowner needs.  相似文献   
958.
《海岸线保护与利用管理办法》是我国专门针对海岸线管理的首部规范性文件,弥补了我国海岸线管理的空缺。文章简要介绍《海岸线保护与利用管理办法》出台的背景;详细分析海岸线保护与利用管理的重要举措:(1)提出自然岸线保有率控制制度,(2)提出海岸线分类保护制度,(3)实施自然岸线保护与利用的年度计划管理,(4)编制全国和省级海岸线整治修复五年规划和年度计划以及建立全国海岸线整治修复项目库;阐述《海岸线保护与利用管理办法》对海岸线保护的作用与意义;最后对全面加强海岸线保护与利用管理提出建立健全各项配套制度、不断完善技术标准体系以及开展海岸线保护管理专项行动的建议。  相似文献   
959.
文章在介绍韩国海洋空间规划的发展沿革和编制流程的基础上,以京畿湾示范工程为例,研究海洋空间规划的编制方法,重点包括建立海洋空间调查和信息体系、开发并应用基于海洋生态系统的管理方法、设定示范海域的核心价值和目标以及促进利害关系人的参与等方面,为完善我国海洋功能区划制度提供借鉴和参考。  相似文献   
960.
近年来,大数据越来越受到计算机、地质、生物、医学等诸多领域的关注且得到了广泛的应用。以世界主要发达国家地质信息服务跟踪为例,针对美、加、英、澳4国的主要地质调查网站及中国知网,运用地质大数据发现技术的网络爬虫方法,获取需求文本数据,进而分析文本内容,总结国外地质信息社会化服务现状。大数据发现技术在地质领域的合理运用,对快速、高效获取图片、文档等数据及降低信息获取成本具有一定的意义。  相似文献   
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