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151.
建立科学规范的本底大气CO2采样观测分析过程中的质量保证与质量控制方法,是实现该数据资源同化和共享的基础.本研究以中国气象局温室气体网络化采样观测经验为基础,以便携式采样观测、波长扫描-光腔衰荡(WS-CRDS)分析技术为例,系统介绍了我国青海瓦里关全球本底站大气中CO2采样观测过程中的质量保证措施,样品分析过程中的玻璃瓶质量保证措施和样品分析过程中的系统质量控制方法、数据处理过程中的校正方法、数据分级质量标记和数据拟合插补方法等;并重点对该方法中几个关键步骤进行了评估验证;最后,应用本研究方法,对我国3个区域大气本底站CO2的采样观测数据进行了处理和浓度变化特征分析,说明本研究方法也可以较好地捕捉区域和局地环境因素影响对观测结果的影响,并客观、准确地反映该区域的自然和人为活动特征. 相似文献
152.
This article is based on an international comparative study analysing innovations in national administrative institutions.
Results of that research are presented and discussed here. Against the background of the institutionalising process of political
institutions the study focused on innovations initiated or introduced by governments or parliaments by example of policies
and politics supporting sustainable development. The countries involved in the original study were Belgium, Denmark, Finland,
France, Germany, the Netherlands, Sweden and the United Kingdom. Three general lessons can be drawn: (1) Countries with a
long tradition of integrated environmental policy-making are more open to the concept of sustainability. (2) A (institutional)
“cure-all” solution does not seem to exist. It seems necessary to diffuse the concept of sustainability into all spheres of
politics and society. Reaching this strategic goal requires a specific policy and polity mix. (3) Strong and well-equipped
institutions result from specific policies and politics: they play a central role in promoting and intensifying sustainable
development. Successful innovations integrating SD into everyday politics and policies are only a very first step though.
Further improvements with regard to effective participation and public debate, global orientation of policies and the measurability
of achieved progress are necessary. 相似文献
153.
154.
Abstract: The unit of trade in ecosystem services is usually the use of a proportion of the parcels of land associated with a given service. Valuing small changes in the provision of an ecosystem service presents obstacles, particularly when the service provides non‐use benefits, as is the case with conservation of most plants and animals. Quantifying non‐use values requires stated‐preference valuations. Stated‐preference valuations can provide estimates of the public's willingness to pay for a broad conservation goal. Nevertheless, stated‐preference valuations can be expensive and do not produce consistent measures for varying levels of provision of a service. Additionally, the unit of trade, land use, is not always linearly related to the level of ecosystem services the land might provide. To overcome these obstacles, we developed a method to estimate the value of a marginal change in the provision of a non‐use ecosystem service—in this case conservation of plants or animals associated with a given land‐cover type. Our method serves as a tool for calculating transferable valuations of small changes in the provision of ecosystem services relative to the existing provision. Valuation is achieved through stated‐preference investigations, calculation of a unit value for a parcel of land, and the weighting of this parcel by its ability to provide the desired ecosystem service and its effect on the ability of the surrounding land parcels to provide the desired service. We used the water vole (Arvicola terrestris) as a case study to illustrate the method. The average present value of a meter of water vole habitat was estimated at UK£12, but the marginal value of a meter (based on our methods) could range between £0 and £40 or more. 相似文献
155.
George E. Radosevich Evan C. Vlachos Gaylord V. Skogerboe 《Journal of the American Water Resources Association》1973,9(2):352-359
ABSTRACT Whether the goal is minimizing water quality degradation in receiving streams or maximizing agricultural production on existing croplands; the solutions are identical - improved water management practices. Technology has succeeded in developing feasible solutions to improving irrigation water management, but the law has been slow to encourage or direct implementation. The villain of the western United States water problem is the property right concept of the appropriation doctrine. Improving water management also implies organizational improvements. Also, the so-called “human factor” involves questions of inefficiency and ineffectiveness, that when examined under the criteria of efficacy, may dictate a policy of continuing present practices in certain localities or regions with little technological intervention. The present effort for improving water quality management implies, therefore, a manyfold attack aimed at increasing project irrigation efficiency and effectiveness, under the larger rubric of efficacy and the achievement of larger social goals. 相似文献
156.
D. C. Williams Donnie L. Daniel 《Journal of the American Water Resources Association》1969,5(3):50-56
This paper focuses on two factors that influence the acceptability of the expected value criterion as a method of handling risk or uncertainty in decision-making where damages from unusual physical occurrences such as hurricanes or floods must be considered. These are the length of time of project existence and the problem of obtaining accurate estimates of the probability of occurrence for different sizes of natural disasters. The problem of estimating accurate probabilities of occurrence for different sizes of natural disasters is not as great as it might appear and in most situations will not defeat the usefulness of the method. The time span during which the project is expected to exist has greater implications for the usefulness of the expected value approach appears highly applicable. However, it becomes less applicable for projects that are short-term in nature. The basis for distinguishing between short- and long-term projects is presented. 相似文献
157.
William M. Park William L. Miller 《Journal of the American Water Resources Association》1982,18(1):89-94
ABSTRACT: There is a long standing hypothesis that overdevelopment has occurred in the nation's floodplains due to imperfect information about the potential flood hazard, an expectation of disaster relief and anticipation of future structural protection. This hypothesis is investigated with multiple regression analysis of data for a case study area. In particular the question of whether floodplain residential property values are fully discounted for expected flood damages is addressed by considering the impact of the National Flood Insurance Program on property values. The extent to which flooding risk perceptions are based on low cost information such as distance from and elevation above the river is also considered. Finally, implications for floodplain management policy are discussed. 相似文献
158.
Jackie Sellers Ronald M. North 《Journal of the American Water Resources Association》1979,15(1):167-181
ABSTRACT: The “principles and standards for planning water and related land resources” were made effective October 25, 1973. The document was noticeably deficient in suggestions for the necessary implementing procedures to ensure its success. Current implementing procedures are based on an incorrect premise of maximizing a single objective subject to non-quantified constraints. A successful implementation of multiple objective planning requires optimizing simultaneously several competitive goals. A system of goal programming has been developed and applied to decisionmaking situations as a test of its usefulness in planning for multiple objective water resources projects. The result is a project planning process which can be replicated for adjustments in expected resource supplies or demands to provide a tradeoff matrix between economic and environmental objectives as well as traditional functional purposes. This procedure, tested on the Cross Florida Barge Canal, is an integrated analysis of economic and environmental values which may be as effective in implementing multiple objective planning as the “Green Book” was in developing the now inappropriate benefit cost analysis. 相似文献
159.
Wynn R. Walker Gaylord V. Skogerboe 《Journal of the American Water Resources Association》1975,11(4):751-758
ABSTRACT: The increased agricultural efficiency of the American farmer has been a substantial impetus to this nation's rapid urbanization. In many western regions where total water supplies are limited, urbanization has required the transfer of heretofore agricultural water rights to the urban use. A major problem in such transfers has been the value or price of the water. A management level model of a typical urban water system was developed to optimize water supply, distribution, and wastewater treatment alternatives. The values of agricultural transfers were determined as the cost advantages of increasing allowable reuse levels of urban effluents which imply the use of a downstream right. This procedure is justified by the economic theory of alternative cost. Results for a test application to the Denver, Colorado area indicate values on the order of $1,000 per acre-foot of transferable water depending on effluent water quality restrictions and operational policies. 相似文献
160.
Bhat MG 《Journal of environmental management》2003,67(4):315-325
The quality of the coral reefs in the Florida Keys is essential to sustain nature-based tourism in the Keys. The recently established marine reserves (MR) are expected to improve the reef environment, particularly coral and fish abundance and diversity. In this paper, a combined model of travel cost and contingent behavior was estimated in order to measure the non-market recreational benefits of reef quality improvements. The results indicated that an average visitor would undertake 43-80% more number of trips to the Florida Keys and experience a 69% increase in the use values per trip, as a result of the MR-induced reef quality improvements. The above non-market value estimates were further applied to evaluating alternative management proposals for funding the MR program. It was found that the annual management costs of the MR program would constitute an insignificant portion--only around one to 2%--of the annual recreational benefits that the MR would generate. The results provide a strong economic justification for designing user-based funding mechanisms in order to make the MR program self-sustaining in the future. 相似文献