我国水资源管理现状及对策

从建立水资源管理体系、水资源管理法规等方面介绍了我国水资源管理的现状，指出我国的水资源管理存在水平落后、市场化程度低、体制和政策上存在弊端以及忽视节水方针的实施等问题，提出了，通过倡导新的生态经济管理思想、建立国家统一的水资源管理体系、以市场为导向进行水资源管理、建设节水型社会和采用先进技术等解决问题的办法。     

A MUNICIPAL WATER SUPPLY INVESTMENT PROBLEM IN RHODE ISLAND1

ABSTRACT: The traditional “requirements” approach to water system planning presumes perfectly inelastic demand and arbitrarily selects a fixed water requirement per capita per day as a planning target. Economists have often pointed out that such a policy leads to over-investment in water supply facilities; a superior approach would maximize some measure of net benefits incorporating price-sensitive demand. Using a dynamic programming model to depict an investment problem in Rhode Island, we find that ambiguities about how to incorporate price-sensitive demand into a decision framework may make such an approach as arbitrary as the requirements approach. Water conservation responses may be a function of other social parameters than water price; if so, variations in these social parameters should be regarded as economic alternatives to water supply investments.     

EFFECT OF PRICE ON THE RESIDENTIAL DEMAND FOR WATER WITHIN AN AGENCY1

ABSTRACT: This paper develops a model that can be used to forecast the residential elasticity of demand for water within a district. Long-term water conservation programs and revenue and cost decisions hinge crucially on a determination of this elasticity. This study then pools cross-sectional (census) and time series data to generate elasticity forecasts for the Oakland urban area.     

Carbon forestry economic mitigation potential in India,by land classification

Carbon forestry mitigation potential estimates at the global-level are limited by the absence or simplicity of national-level estimates, and similarly national-level estimates are limited by absence of regional-level estimates. The present study aims to estimate the mitigation potential for a large diverse country such as India, based on the GTAP global land classification system of agro-ecological zones (AEZs), as well the Indian AEZ system. The study also estimates the implications of carbon price incentive (US$50 and $100) on mitigation potential in the short-, medium- and long-term, since afforestation and reforestation (A & R) is constrained by lack of investment and financial incentives. The mitigation potential for short and long rotation plantations and natural regeneration was estimated using the GCOMAP global forest model for two land area scenarios. One scenario included only wastelands (29 Mha), and the second enhanced area scenario, included wastelands plus long fallow and marginal croplands (54 Mha). Under the $100 carbon price case, significant additional area (3.6 Mha under the wasteland scenario and 6.4 Mha under the enhanced area scenario) and carbon mitigation is gained in the short-term (2025) compared to the baseline when using the GTAP land classification system. The area brought under A & R increases by 85–100% for the $100 carbon price compared to $50 carbon price in the short-term, indicating the effectiveness of higher carbon price incentives, especially in the short-term. A comparison of estimates of mitigation potential using GTAP and Indian AEZ land classification systems showed that in the short-term, 35% additional C-stock gain is achieved in the $100 carbon price case in the enhanced area scenario of the Indian AEZ system. This difference highlights the role of the land classification system adopted in estimation of aggregate mitigation potential estimates, particularly in the short-term. Uncertainty involved in the estimates of national-level mitigation potential needs to be reduced, by generating reliable estimates of carbon stock gain and losses, and cost and benefit data, for land use sector mitigation options at a scale disaggregated enough to be relevant for national mitigation planning.     

小城镇废品回收利用的制约因素分析——关于黑龙江省密山市裴德镇的调查

目前小城镇日常生活中可回收利用的废品主要是通过废品回收部门流向废品再利用工厂.废品回收部门主要依赖于废品再利用工厂生存.规模较大的个人废品收购商对专业化废品收购商的冲击以及废品再利用工厂的收购价格低、技术水平低、有限的收购种类和二次污染严重等已成为废品向资源化产品转化的制约因素.完善废品回收利用渠道和加强政府的支持力度对于促进废品类物质的资源化具有重要意义.     

土地利用线性规划结果的影子价格计算与敏感性分析

在土地利用规划中,对线性规划结果进行影子价格计算可以确定其结果在最优状况时,放宽某个约束条件(a_ijx_i=b_i)对目标函数（S）产生的附加贡献值。而敏感性分析解决了在线性规划仍保持最优解情况下,所允许的因市场条件和生产过程的改变导致的资源限制且（b_i）和利益系数（c_i）的可行变化范围。通过以上计算和分析,使静态的线性规划模型向动态模型方向迈进了一步。为其在一定空间和时间上推广应用开拓了余地。     

工程项目投标报价优化方法

随着市场经济体制的建立与完善，投标竞争越来越激烈，要在投标竞争中取胜，制定合理的投标报价策略就显得尤为重要，本文探讨了运用概率分析方法，针对不同的竞争对手进行投标报价的技术与方法。     

影子价格─自然灾害经济评价中合理的价格

着重说明自然灾害经济评价中利用影子价格的原因，简要说明我国目前在投资项目评价中采用的影子价格及计算方法，以及在自然灾害经济评价中如何利用影子价格进行计算．     

猪肉价格周期波动的时空差异特征及影响因素研究

我国作为猪肉生产大国、消费大国,猪肉价格波动事关普通百姓生活。利用2001—2019年猪肉价格省级面板数据,对猪肉价格长期波动的空间差异性进行了分析。结果表明:①从我国八大经济区及调入区、调出区猪肉价格区域差异测度结果来看,北部沿海区域内各省份猪肉价格差异最大,东北区域和长江中游区域差异较小;同时从猪肉价格差异贡献率来看,区域内差异贡献率更大。②从猪肉价格波动时空演进测度结果来看,地区间差异明显存在,同时各省份之间空间集聚性呈现出波动状态,表现出先减弱后增强的长期趋势。③从对猪肉价格周期性变化规律分析结果来看,价格波动存在明显的周期性,“猪瘟”、重大疫情等突发因素短期影响作用较大,而常规因素的影响才是价格波动真正推手。④在所筛选的猪肉价格常规影响因素中,育肥猪配合饲料价格、仔猪价格、地区生产总值引起猪肉价格差异的作用显著,且育肥猪配合饲料价格对猪肉价格差异影响程度最大。     

北京都市区土地价格梯度估算与解析

文章简要梳理了国内外地产价格梯度案例研究的脉络,采用特征价格模型、非参数估计方法研究了北京都市区住宅、商业土地出让价格梯度与土地开发强度的变化,解析了新时期城市空间发展的特征。研究表明:住宅和商业土地出让价格梯度随时间呈现扁平化倾向,从土地价格视角说明了北京城市空间持续的郊区化扩展趋势。2009年以来住宅土地价格梯度为正,表明北京住宅空间结构特征不完全符合单中心城市假设,商业地块则较好地体现出市场机制下价格梯度的变化规律。线性模型在刻画住宅土地开发强度的空间变化方面不典型,但却较好地揭示了商业土地随到城市中心距离的增加,开发强度逐步降低的特征,2005年以来这种特征有所缓和。非参数估计方法由于不需要预设函数形式,有效避免了城市中心预设和模型选取引致的估计偏误,应用非参数方法中的核估计拟合北京住宅土地出让价格、开发强度与距离之间的曲线,能够描绘出变量之间的复杂关系,更符合北京都市区的实际。