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181.
为系统探讨陕西省水文化遗产的保护与利用,丰富相关理论与实践,按照理论分析-现状分析-对策研究的思路,从陕西省水文化遗产内涵与价值分析出发,对陕西省水文化遗产构成类型进行梳理,指出陕西省水文化遗产历史深厚、类型多样、地域特色明显,河流、水利工程等资源等级较高,诗词、碑刻、民俗等资源存世量大。分析当前在认识理念、管理体制、保护经费等方面存在的问题,提出陕西省水文化遗产建设应着眼于以生态系统修复、人文系统重构、价值系统重塑、产业系统创新、管理系统再造的"全域统筹、理念重构"和基于遗址遗迹型、工程功能型和非物质文化型遗址功能与特征的"分类保护、层级联动"两大核心策略,兼顾"点、线、面"3个空间要素,构建陕西省水文化"点状布局、线状串联、流域覆盖"大遗产格局。  相似文献   
182.
A spatially explicit model of the optimal timing and location of land development is presented that incorporates dynamic interactions between land development and water quality. Ignoring two-way interactions leads to a lower level of water quality, more development, and lower social welfare. The optimal pace and pattern of development can be achieved through the assessment of an impact fee that internalizes pollution damages and irreversibility costs. Our results demonstrate the importance of accounting for the spatial dimension of land use, the interdependence between land use and environmental quality, and development irreversibility in models of urbanization and amenity-driven growth.  相似文献   
183.
济南市水资源承载力及可持续利用对策   总被引:2,自引:0,他引:2  
水是人类生存和发展的物质基础,但随着社会经济的发展,水的供需矛盾日益尖锐,水资源承载力成为水资源安全战略研究的一个基础;通过对济南水资源承载力分析和预测,为可持续发展提供对策.  相似文献   
184.
The paper estimates an aggregate daily water demand for Sydney using rainfall, temperature, and price data from 2001 to 2005, and a dummy variable to account for reductions in demand following the introduction of water restrictions in October 2003. Analyses based on the estimated price elasticity, and also values one and two standard errors above and below this estimate, are used to model the effects of different pricing and water supply scenarios. The simulations indicate that without a fundamental change in water policy (pricing and supply) Sydney faces the possibility of critical water shortages in the short- to medium-term should there be a continuation of low rainfall events.  相似文献   
185.
以COD作为评价因子,对扩改工程造低废水排入长江后对长江的影响程度与范围进行了预测,得出在正常排放情况下影响较小,在非正常放情况下影响较大,同时提出了控制水污染的措施。  相似文献   
186.
Using economic analysis to prioritise improvements in environmental conditions is particularly difficult when multiple benefits are involved. This includes ‘bundling’ issues in agricultural pollution management, where a change in management action or farming systems generates multiple improvements, such as reductions in more than one pollutant. In this study, we conceptualise and compare two different approaches to analysing cost‐effectiveness when varying bundles of benefits are generated for a single project investment. Each approach requires data to be transformed in some way to allow the analysis to proceed. The index approach requires the transformation on the benefits side so that the effects of multiple pollutant changes can be combined into a measure for each project which can then be compared to costs. By comparison, the disaggregation approach requires the transformation on the costs side where costs for each project have to be apportioned across the different pollutants involved. The paper provides novel insights with an application to agricultural water quality improvements into the Great Barrier Reef in Australia, demonstrating that while both approaches are effective in prioritising projects by cost‐effectiveness, the disaggregation approach provides more insightful results and values that may be relevant for use as upper value guidelines in future project selection.  相似文献   
187.
Using prices to improve the efficiency with which water resources are allocated is now widely accepted in principle if somewhat difficult to achieve in practice. Whilst there are some technical difficulties associated with full‐cost recovery in irrigation, the lack of political will to tackle reform remains a significant impediment. This article reports the results of an empirical investigation into farmers’ preferences for changes to water prices and tariff structures. We conclude that some of the preferences of farmers are conducive to price reform. We also find evidence that public subsidy of infrastructure in irrigation is not always aligned with the preferences of farmers.  相似文献   
188.
松嫩平原北部黑土区水土资源平衡效应研究   总被引:1,自引:0,他引:1  
研究目的:分析松嫩平原北部黑土区在土地利用和农业气候资源变化条件下的水土资源平衡效应。研究方法:在傅抱璞假设理论的基础上,通过拟合参数ω回归方程求得实际蒸散量,以此来构建水分盈亏模型,分析水土资源平衡效应。研究结果:(1)1985—2015年,松嫩平原北部土地利用表现为湿地面积大幅度减少,水田和旱地面积不断增加;潜在蒸散量和气温具有较为明显的变化趋势,气温以0.27℃/10 a上升,潜在蒸散量以5.15 mm/a下降;(2)经过拟合参数ω方程求得实际蒸散量可以有效反映土地利用状况、地貌特征和土壤属性;(3)1985—2015年间总体的水分亏缺率均值是0.25、0.2、0.31和0.13,而土地利用的影响使严重缺水面积逐年增加,其增加量是总面积的1.59%,约是原有面积的2倍。研究结论:基于傅抱璞理论改进的参数ω能够提高地区实际蒸散量的估算精度,对区域水土平衡评价具有重要意义,为实现区域资源合理利用提供指导。  相似文献   
189.
This paper proposes a system of tradable Water Saving Certificates to improve the efficiency of water allocation between Drinking Water Utilities at river basin level. A market institutional set‐up, inspired from recent policy developments in the energy sector, is proposed. An original analytical price‐endogenous model is developed to simulate trade intensity, equilibrium price and efficiency gains in this urban water market. The economic model is implemented in a French case study using mathematical programming. It is used for conducting an ex‐ante evaluation of trade possibilities and efficiency gains, considering different spatial restrictions aimed at controlling environmental externalities. Our modelling exercise provides evidence of the benefits of the proposed Water Saving Certificate scheme.  相似文献   
190.
为落实党中央国务院关于建设和运用水市场、提高水资源配置效率和效益的重要部署,推进我国水权制度建设,对宁夏回族自治区、内蒙古自治区和广东省水权水市场建设的实践开展调研。总结我国各地区水权交易制度建设的路径、模式和经验,通过实地调研、座谈、资料收集等定量研究方法,分析3个典型省份的案例,明确了建设水权交易制度在提高水资源利用效率、拓宽水利设施融资渠道等方面的积极作用,提出有关省区在实践中存在过分强调政府作用、定价机制不完善、缺乏社会参与、水资源监控能力不够等问题,并针对性地提出健全水权交易制度、建立价格形成机制、构建多层次交易平台、构建有效监督体系等政策建议。  相似文献   
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