Renewable Resources in an Overlapping Generations Economy Without Capital

We incorporate a renewable resource into an overlapping generations model without capital and with quasi-linear preferences. Besides being an input for production the resource serves as a store of value. We characterize the dynamics, efficiency, and stability of the steady-state equilibria. The stability properties are sensitive to the type of resource growth. For constant growth there is only one steady-state equilibrium which is stable and efficient. In the general case of the concave growth function, there are usually at least two steady-state equilibria, one of which is stable and the other one unstable. The unstable steady state is efficient, but the stable one may or may not be. We study the robustness of our results by assuming a logarithmic utility function. We show that for the Cobb–Douglas production function the steady state is unique and stable regardless of whether the equilibrium is efficient or inefficient. Our analytical results are illustrated by numerical calculations.     

Sustainability: a Dissent

Abstract:  Broadly conceived and considered in its many usages, sustainability has grave defects as a planning goal, particularly when used by conservationists: it confuses means and ends; it is vague about what is being sustained and who or what is doing the sustaining; it is uninspiring; it is little more than Pinchot-era conservation (and thus ignores the many lessons learned since then); it need not be linked to land, to the land's functioning, or to any ecological science; it need not include a moral component; it is consistent with the view of humans as all-powerful manipulators of the planet; and, in general, it is such a malleable term that its popularity provides only a facade of consensus. When sustainability is defined broadly to include the full range of economic and social aspirations, it poses the particular risk that ecological and biodiversity concerns will be cast aside in favor of more pressing human wants. Given these many defects, the conservation movement should discard the term in favor of a more alluring goal, attentive to nature and its ecological functioning. A sound goal would incorporate and distill the considerable ecological and moral wisdom accumulated since Pinchot's day while giving conservationists the rhetorical tools needed to defend the land against competing pressures. In our view, conservation would be well served by an updated variant of "land health," Aldo Leopold's ecologically grounded goal from the 1940s. Land health as an independent understanding should set the essential terms of how we live and enjoy the earth, providing the framework within which we pursue our many social and economic aims.     

黄冈市矿业经济布局研究

文章针对黄冈市矿业经济发展的需要，在充分考虑黄冈市地区经济发展，矿产资源分布，矿业经济合理布局的必要性的基础上，对黄冈市矿业经济布局作了详细深入研究，提出了“一个中心，四个矿业规划区，五类开发矿种，十个矿业基地”的布局构架，为该市矿业经济发展提供了明确的发展思路，并指出了发展重点，也为政府宏观调控和矿政管理提供了依据。     

矿产资源的开发利用与环境保护

作者论述了人口、资源、环境三者之间的辩证关系，提出环境保护是矿产资源开发利用的前提，不能以牺牲环境为代价来开发利用矿产资源。以此为基点，作者概述了我国矿产资源开发利用对环境的影响，以及我国矿山环境保护工作的现状，提出了加强矿产资源开发利用中环境保护的五项建议。     

矿井水是宝贵的地下水资源

本文针对煤矿矿井水是废水的错误认识，深入浅出地讨论了矿井水的水质特征，鲜明地提出矿井水是宝贵的地下水资源的观点，以及矿井水资源化的法规保证。     

西藏自治区土地资源的适宜性评价与利用

本文综合评价了西藏自治区土地资源的适宜性及其质量．阐明了影响土地资源潜力发挥的主要限制因素，分析了土地资源利用现状、存在问题和开发潜力。并在此基础上、提出了西藏自治区土地资源合理开发利用的方向、对策和措施。     

减缓贫水化过程的途径再议

根据贫水化的严重形势，应用水循环的原理，提出了减缓贫水化的几个主要途径，对解决城市淡水短缺有参考意义。     

OPTIMIZATION MODELING OF A NEW FACILITY FOR THE CALIFORNIA STATE WATER PROJECT1

ABSTRACT: A non-linear optimization model is applied to the California State Water Project (SWP) and portions of the Central Valley Project (CVP). The model accounts for the major hydrologic, regulatory, and operational features of both projects. The model maximizes long-term SWP yields over a 70-year period, using a quarterly time step. The potential for increased yield associated with a proposed facility improvement is evaluated with the model. The proposed facility is an extension of the Folsom-South Canal, which would allow water to be conveyed from the American River below Folsom Reservoir into New Melones Reservoir on the Stanislaus River or into the California Aqueduct. Model results indicate that extension of the Folsom-South Canal has the potential to increase SWP yields by 13 percent.     

信息时代的数字图书馆

数字图书馆是将文字、图像、声音等信息数字化,通过国际互联网传输,做到信息资源全球共享.数字图书馆拥有丰富的多种媒体数字化信息资源,是没有时空限制的超大规模知识中心.     

黄山地区野生蔬菜资源的开发利用

黄山地区野生蔬菜资源丰富，约有300多种，且蕴藏量大。对黄山地区野生蔬菜资源的利用状况进行了分析，并对其合理开发利用提出了建议，以期为黄山地区的生态旅游和经济发展提供参考。