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181.
为明确能源作物柳枝稷在缺钾条件下的耐受能力,筛选出耐贫瘠性强的优质种质资源,以13个柳枝稷品种为供试材料,在人工气候室中开展水培试验,通过相关农艺性状和生理指标等评价指标的测定,采用标准差系数赋予权重法对柳枝稷在缺钾胁迫下的表现做出综合评价。结果表明:在缺钾胁迫下,13个柳枝稷品种地上及地下部的生长均受到显著抑制,具体表现为:生长速度下降,叶绿素含量减少,光合面积减少,光合速率降低,进而导致其总生物量积累下降。由标准差系数赋予权重法得出的13个品种耐胁迫性由高到低依次为:Cave—In—Rock、Trailblazer、BJ-5、Forestburg、BJ-4、Pathfinder、BJ~3、BJ一2、Blackwell、Alamo、BJ-1、BJ-6、Kanlowo 相似文献
182.
青藏高原重点区域工业布局的战略构想 总被引:3,自引:0,他引:3
论文认为在青藏高原具有相对比较优势的重点区域 ,应大力发展具有特色的现代工业。作者重点分析了高原重点区域工业发展的总体思路和战略目标 ,指出了工业发展的总体方向和区域工业布局框架设想。从协调好高原各个产业之间的相互关系出发 ,文章认为在高原重点区域应大力发展以钢铁-铁合金-有色-黄金为主的冶金工业 ,以盐化和油气化工为主的化学工业 ,以满足高原内部需要的建材工业 ,以及具有一定基础的机电-轻纺和藏民族手工业。 相似文献
183.
Basharat A. Pitafi James A. Roumasset 《Journal of the American Water Resources Association》2006,42(6):1441-1450
Abstract: Conserving the watershed can help to preserve ground water recharge. Preventing overuse of available water through pricing reforms can also substantially increase the value of an aquifer. Inasmuch as users are accustomed to low prices, efficiency pricing may be politically infeasible, and watershed conservation may be considered as an alternative. We estimate and compare welfare gains from pricing reform and watershed conservation for a water management district in Oahu that obtains its water supply from the Pearl Harbor aquifer. We find that pricing reform is welfare superior to watershed conservation unless the latter is able to prevent very large recharge losses. Watershed conservation that yields net gains in combination with pricing reform may cause net losses without the pricing reform. If adoption of watershed conservation delays the implementation of pricing reform, the benefits of the latter are significantly reduced. 相似文献
184.
Scott N. Ralston William M Park 《Journal of the American Water Resources Association》1989,25(6):1259-1265
ABSTRACT: A travel cost model is developed to estimate the potential reductions in recreational benefits from sedimentation in Reelfoot Lake in northwestern Tennessee. In addition to the consumer surplus estimates generated by the model, three other aspects of the study were significant. First, the study applied a relatively untested methodology for deriving the opportunity cost of travel time. The study resulted in a value that is less than one-half of the Water Resource Council's “one-third of the wage rate” rule-of-thumb. Second, water quality perceptions were unsuccessfully incorporated into the model as a demand shifter. This raised questions as to the appropriate manner in which perceptions could be included in a travel cost model. Finally, a simple methodology was outlined by which estimates of the recreational value of Reelfoot Lake could be used to suggest how much cost could be justified for soil erosion control on agricultural land surrounding the lake. 相似文献
185.
We present a framework of a scenario-based model that simulates the development of the municipality of Davos (Swiss Alps).
We illustrate our method with the calculation of the scenario for 2050 “Decrease in subsidies for mountain agriculture and liberalization of markets.” The main objective was to link submodels of land-use allocation (regression-based approach), material and energy flows submodels
(Material and Energy Flux Analysis), and economic submodels (Input–Output Analysis). Letting qualitative and quantitative
information flow from one submodel to the next, following the storyline describing a scenario, has proven to be suitable for
linking submodels. The succession of the submodels is then strongly dependent on the scenario. Qualitative information flows
are simulated with microsimulations of actor choices. Links between the submodels show different degrees of robustness: although
the links involving microsimulations are the weakest, the uncertainty introduced by the land-use allocation model is actually
advantageous because it allows one possible change in the landscape in the future to be simulated. The modeling results for
the scenario here presented show that the disappearance of agriculture only marginally affects the region’s factor income,
but that the consequences for the self-sufficiency rate, for various landscape-related indicators and ecosystem services,
and for the economy in the long term may be considerable. These benefits compensate for agriculture’s modest direct economic
value. The framework presented can potentially be applied to any region and scenario. This framework provides a basis for
a learning package that allows potential detrimental consequences of regional development to be anticipated at an early stage. 相似文献
186.
Lisa A. McDonald Grace M. Johns 《Journal of the American Water Resources Association》1999,35(3):579-592
ABSTRACT: Successful watershed management requires consideration of multiple objectives and the efficient use of scarce public and private resources. One way to address these multi-faceted issues is through Social Benefit-Cost Accounting (SBCA). SBCA is a systematic method of addressing complex social and economic issues relevant to proposed watershed management projects. Benefits of using this technique include: benefits and costs of watershed projects are better understood; politically sensitive issues tend to be put into perspective; and stakeholders' interests are placed on a level playing field. An example from Bogota, Colombia demonstrates how SBCA can be used to value the benefits and costs of a proposed project. By addressing the benefits and costs to all stakeholders, the design of watershed management programs can be improved to achieve goals in a cost-effective manner. 相似文献
187.
Domestic water conservation in arid climates can result in efficient utilization of existing water supplies. The impacts of
conservation measures such as the installation of water-saving devices, water metering and pricing schemes, water rationing
and public awareness programs, strict plumbing codes, penalties for wasting water, programs designed to reduce leakage from
public water lines and within the home, water-efficient landscaping, economic and ethical incentives are addressed in detail.
Cost savings in arid climates, with particular reference to Saudi Arabia, in relation to some conservation techniques, are
presented. Water conservation technology and tentative demonstration and implementation of water conservation programs are
discussed. 相似文献
188.
吕桂景 《中国环境管理干部学院学报》2006,16(4):34-36
环境会计的研究落脚到建筑行业中,有利于在研究中加强环境科学与会计理论的结合,充分利用环境学中的技术方法,探索环境成本的核算方法,为建筑行业的发展提供一个有效管理工具,同时也为环境会计的建立寻找突破口做出创新创造条件. 相似文献
189.
ABSTRACT: This study investigates the degree of economic inefficiency of the current institutional arrangements for surface and ground water management in meeting urban water demand in the Jakarta region. A numerical model of integrated surface and ground water management is developed using GAMS (General Algebraic Modelling System) software. The model maximizes the net present value of social benefits from piped water and ground water consumption across all users over time from 1999 to 2025. Four policy scenarios are examined: the status quo, the social planner's solution, and two ground water pumping quota scenarios: an aggregate ground water pumping quota and a partial quota applied to commercial and industrial users. Three variations in each policy scenario are considered: investment in water infrastructure of the Jakarta water enterprise (PAM Jaya), water demand growth, and discount rates. The status quo, depending on the investment option, the growth of water demand, and the discount rate, results in a 7.4 to 47.8 percent loss in economic efficiency relative to the social planner's solution. The partial quota is the most feasible, applicable, and manageable scenario. The optimal investment option could increase the volume of piped water supply and reduce the cost of water production. The volume of water delivery could increase by up to 156 percent, but it implies only a 35 percent increase in the surface raw water demands above the current level. However, it does not significantly reduce cumulative ground water extraction over the time period considered. 相似文献
190.
Mohammed M. Al‐Sabbry DeVerle Harris Roger Fox 《Journal of the American Water Resources Association》2002,38(1):119-131
ABSTRACT: Bringing water from Colorado River via the Central Arizona Project was perceived as the sole solution for Tucson Basin's water problem. Soon after Central Arizona Project's water arrived in Tucson in 1992, its quality provoked a quarrel over its use for potable purposes. A significant outcome of that quarrel was the enactment of the 1995 Proposition 200. The Proposition 200 precludes the use of Central Arizona Project's water for potable purposes, unless it is treated. Yet, it encourages using it for non‐potable purposes and for replenishing the Tucson aquifer through recharge. This paper examines the economic issues involved in utilizing Central Arizona Project's water for recharge. Four planning scenarios were designed to measure and compare the costs and benefits with and without Central Arizona Project's water recharge. Cost‐benefit analysis was utilized to measure recharge costs and benefits and to derive a rough estimate of cost savings from preventing land subsidence. The results indicate that the institutional requirements can be met with Central Arizona Project's water recharge. The economic benefits from reducing pumping cost and saving groundwater are not economically significant. Yet, when combining the use of Central Arizona Project's water for recharge and non‐potable purposes, it demonstrates positive net economic benefits. 相似文献