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141.
Richard M. Vogel Neil M. Fennessey 《Journal of the American Water Resources Association》1995,31(6):1029-1039
ABSTRACT: A streamflow duration curve illustrates the relationship between the frequency and magnitude of streamflow. Flow duration curves have a long history in the field of water-resource engineering and have been used to solve problems in water-quality management, hydropower, instream flow methodologies, water-use planning, flood control, and river and reservoir sedimentation, and for scientific comparisons of streamflow characteristics across watersheds. This paper reviews traditional applications and provides extensions to some new applications, including water allocation, wasteload allocation, river and wetland inundation mapping, and the economic selection of a water-resource project. 相似文献
142.
A. R. Ghanbari Parsa A. R. Mandani Pour 《Journal of Environmental Planning and Management》1988,31(2):110-115
In the aftermath of the 1979 revolution, the new administration adopted a number of policies to address the question of land ownership, supply and allocation in order to tackle the acute shortage of housing in the urban areas. In 1982, the Five‐Year Urban Land Act was passed by the Parliament. Subsequently a body called the Urban Land Organisation (ULO) was set up to co‐ordinate the process of land preparation and allocation. The 1982 Urban Land act empowered the government to: (a) expropriate certain categories of abandoned urban land, and (b) to set a temporary time schedule of five years during which the act's work will be monitored.
This paper sets out to examine the policies related to urban land which have been introduced and implemented in the 1980s in Iran. 相似文献
143.
ABSTRACT: Under the riparian doctrine of eastern states, transfers of water to nonriparian lands and, thus, to different river basins, are only possible if the natural flow theory has been modified to allow for reasonable use. Even this adaptation is too nebulous to provide water managers and water users with certainty regarding water transfers. To provide a more precise mechanism for allocating water, 14 eastern states have adopted some form of administrative permitting process. Of these, five states statutorily allow for interbasin transfers of water. Thus far, no states have successfully issued permits for interbasin water transfers but Georgia and South Carolina are positioned to do so. Whether the permitting process will deter court action may rest on the ability of affected parties to negotiate an equitable agreement. 相似文献
144.
ABSTRACT: A model is proposed for allocation of water shortages among competing water uses in the Svarta River basin in Sweden. The three major competing uses in the basin are hydroelectricity generation, irrigation water supply, and urban water supply. Minor uses that impact upon the allocation are minimum river flow requirements for fishlife and for dilution of treated wastewater, and storage level restrictions for recreation purposes in the main storage facility, Lake Sommen. Analysis of the competing demands on the water are modeled through the method-of-weights multiobjective technique using a deterministic mixed-integer optimization formulation. The (0–1) variables in the formulation are required to synthesize the restricted validity of permits for withdrawal of irrigation water from the river and to simulate the complex operating rules of the major regulation facility on the river. Due to the deterministic nature of the formulation, the model is used on a hydrologic scenario basis. Use of the model is demonstrated by application to the Svarta River. 相似文献
145.
开展工业行业碳排放绩效研究,对于落实碳减排承诺、完善碳交易体制、推动低碳产业发展具有重要意义。采用郑州市2013年181家工业企业的基础数据,通过构建碳排放综合绩效指标体系和配额分配模型,开展不同行业的综合绩效评价和配额分配模拟。主要结论如下:(1)不同行业的碳排放强度分布极不均衡且与碳排放总量具有一定的关联性,但关联类型不尽相同。电力、热力生产和供应业的碳排放强度最高(5.4115 t/万元),烟草制品业的碳排放强度最低(0.0046 t/万元)。(2)不同行业单位用地碳排放量、单位劳动力碳排放量差异较大。电力、热力生产和供应业的单位用地碳排放及单位劳动力碳排放明显高于其他行业。(3)碳排放综合绩效表明,电力、热力生产和供应业的碳排放绩效最低,汽车制造业的碳排放绩效最高。(4)不同行业因综合绩效的差异获得与基准年碳排放不同增减比例的配额,其中,电力、热力生产和供应业获得的配额最多,化学纤维制造业获得的配额最少。通过碳配额分配模拟,郑州市整体减排18.206万t,减排比例为5.56%。(5)建议完善行业配额分配方案,并试点实施以碳排放综合绩效评价为基础的行业配额分配,实现资源节约、环境保护和碳减排的协同。 相似文献
146.
Land use/cover in Northeast China went through extensive changes during the 1990s. This report explores the interaction between
these changes and the environment, and the implication of these changes for rational allocation of water resources. Two maps
of land use/cover produced from 1990 and 2000 Landsat TM satellite images were overlaid in ArcInfo to reveal changes in land
cover. Results indicate that farmland and grassland decreased by 386,195 and 140,075 ha, respectively, while water, built-up
areas, and woodland increased by 238,596, 194,231, and 192,682 ha, respectively. These changes bore a mutual relationship
with the environmental change. On the one hand, climate warming made some of these changes (e.g., conversion of woodland and
grassland to farmland) possible. On the other hand, the changed surface cover modified the local climate. These changes, in
turn, caused severe environmental degradation and increased flooding. The change between dry field and rice paddy, in particular,
raised severe implications for the proper allocation of limited water resources in the Northeast. Efforts are needed to coordinate
their rational allocation to reap maximum and sustainable return over the entire area, not just in some localities. Results
obtained in this study should be of interest to the international audience of Environmental Management in that they highlight the interactive nature of human activities and the environment and the off-site impact of these activities
on the environment. 相似文献
147.
Rogier E. Hintzen Marina Papadopoulou Ross Mounce Cristina Banks-Leite Robert D. Holt Morena Mills Andrew T. Knight Armand M. Leroi James Rosindell 《Conservation biology》2020,34(3):721-732
Conservation biology was founded on the idea that efforts to save nature depend on a scientific understanding of how it works. It sought to apply ecological principles to conservation problems. We investigated whether the relationship between these fields has changed over time through machine reading the full texts of 32,000 research articles published in 16 ecology and conservation biology journals. We examined changes in research topics in both fields and how the fields have evolved from 2000 to 2014. As conservation biology matured, its focus shifted from ecology to social and political aspects of conservation. The 2 fields diverged and now occupy distinct niches in modern science. We hypothesize this pattern resulted from increasing recognition that social, economic, and political factors are critical for successful conservation and possibly from rising skepticism about the relevance of contemporary ecological theory to practical conservation. 相似文献
148.
Mark P. Smith 《Journal of the American Water Resources Association》2009,45(5):1100-1115
Abstract: This paper reviews several recent case studies in which states or countries have strengthened their protection of environmental flows to explore the key policy, stakeholder, and scientific elements that contributed to these advances in water management. A conceptual framework is developed to describe the actions of interest groups and individuals, how environmental flow issues get onto the formal agenda of decision makers, the events and conditions which precipitate this attention, the role of science and scientific uncertainty, and how interactions and dialog among individuals and groups with different interests lead to changes in state and national statutes. In general, the review found that changing policies is a result of actions of informed groups of interested parties using science and information to inform both the public and decision makers about the need for action and about the specific action needed. In almost all cases, environmental flow issues make it onto the formal agenda of institutions through one or more precipitating events, often legal challenges that call into question the existing legal framework for water management. Significantly, in almost all cases the engagement between advocacy coalitions with different and often opposing views results in reframing the issues to provide a common approach or solution upon which the competing coalitions can agree. 相似文献
149.
Yingying Wu 《中国人口.资源与环境(英文版)》2014,(2)
In this paper,interest allocation in the resource industry chain is studied taking resources exploitation in China as an example.First,qualitative analysis is used to conclude stakeholders and their relationship in mineral resource exploitation.In the following section,using the tool of price constitution and comparison method,the research on interest allocation along the industry chain shows that midstream and downstream companies have advantages.The next section studies interest allocation among resource owners,exploitation companies and local governments.Through contrastive analysis of the financial report of petroleum companies,this paper quantitatively measures the scale of revenue shifting from resource owners,the central and local governments to exploitation companies.This contorted interest allocation is an important factor resulting in exploitation confusion and the large revenue gap. 相似文献
150.
成都市生态城市建设的路径设计 总被引:5,自引:0,他引:5
文章结合成都市自然资源的优势和特点,依据生态原理的基本思想,从城市河流生态的保护与建设;成都绿化的生态建设与城市生态社区示范建设;城乡融合生态系统的基本设计;成都郊县市生态农业、生态聚落的建设和生态建设总体布局与功能分区等五个方面进行了具体的分析,提出了相关的设计路径和措施。 相似文献