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1.
Wetland mitigation banking is an American neoliberal environmental policy that has created a functioning market in `ecosystem services', commodities defined using the holistic measures of ecological science. The development of this market is discussed as a project of environmental governance, defined as the nation-state's regulation of ecological relations within its territory towards stabilizing capitalist relations of power and accumulation. I argue that the wetland banking industry serves as a bellwether that presages problems that other strategies of neoliberal environmental governance will experience. Ethnographic, economic and ecological data from the Chicago-area wetland banking industry inform a discussion of two major obstacles to neoliberal strategy: the problem of relying on ecological science to define the unit of trade, and the problem of aligning the somewhat independent relations of law, politics, markets and ecosystems across an array of spatial scales. Theoretical guidance is sought from recent work on `social natures' and from the Regulationist approach to institutional political economics.  相似文献   
2.
钢筋混凝土建筑抗倒塌设计   总被引:14,自引:2,他引:14  
建筑抗倒塌问题近年来在欧美国家得到广泛关注,并颁布了相关的设计规范和标准。我国还没有制定有关建筑抗倒塌方面的规范和标准。本文提出一种基于建筑危险性的钢筋混凝土建筑抗倒塌设计方法。该方法将钢筋混凝土建筑分为四类,通过设置拉杆连接系统和Alternate Path设计提高建筑抗倒塌能力。  相似文献   
3.
《Climate Policy》2013,13(1):111-117
Abstract

This article evaluates the environmental effectiveness and economic efficiency of the Kyoto Protocol after the Bonn Agreement and the Marrakesh Accords. The US withdrawal has by far the greatest impact in reducing the environmental effectiveness, lowering the price of traded emission permits and reducing Annex I abatement costs. The decisions on sinks imply that the Annex I CO2-equivalent emissions without the US will come out at about 1/2% below base-year level, instead of over 4% below base-year level. Without US participation, the emission permit price is estimated to be low. Therefore, banking hot air by Russia and the Ukraine is of absolute importance for the development of a viable emissions trading market, and would also enhance the environmental effectiveness of the Kyoto Protocol.  相似文献   
4.
Surveying co-located space-geodetic instruments for ITRF computation   总被引:2,自引:2,他引:0  
A new and comprehensive method is presented that can be used for estimating eccentricity vectors between global positioning system (GPS) antennas, doppler orbitography and radiopositioning integrated by satellites (DORIS) antennas, azimuth-elevation (AZ-EL) very long baseline interferometry (VLBI) telescopes, and satellite laser ranging (SLR) and lunar laser ranging (LLR) telescopes. The problem of reference point (RP) definition for these space-geodetic instruments is addressed and computed using terrestrial triangulation and electronic distance measurement (EDM) trilateration. The practical ground operations, the surveying approach and the terrestrial data processing are briefly illustrated, and the post-processing procedure is discussed. It is a geometrically based analytical approach that allows computation of RPs along with a rigorous statistical treatment of measurements. The tight connection between the geometrical model and the surveying procedure is emphasized. The computation of the eccentricity vector and the associated variance–covariance matrix between an AZ-EL VLBI telescope (with or without intersecting axes) and a GPS choke ring antenna is concentrated upon, since these are fundamental for computing the International Terrestrial Reference Frame (ITRF). An extension to RP computation and eccentricity vectors involving DORIS, SLR and LLR techniques is also presented. Numerical examples of the quality that can be reached using the authors approach are given. Working data sets were acquired in the years 2001 and 2002 at the radioastronomical observatory of Medicina (Italy), and have been used to estimate two VLBI-GPS eccentricity vectors and the corresponding SINEX files.  相似文献   
5.
哈大高铁对东北城市旅游经济联系的空间影响   总被引:10,自引:5,他引:5  
基于GIS平台,构建可达性模型分析哈大高铁开通后东北各城市旅游交通网络可达性变化特征,然后通过修正引力模型,从时空压缩效应、高铁旅游带的形成、旅游通勤圈空间分异、加剧旅游极化效应等方面分析哈大高铁对东北各城市间旅游经济联系的影响。结果显示:高铁带来的时空压缩效应大大强化了东北城市的旅游交通可达性和旅游经济联系,整个通勤圈时空压缩2 h左右,提升幅度均呈现距离高铁增加而衰减现象,且省际城市间的变化大于省内城市间的变化,东三省的变化大于内蒙东部区域的变化。沿线城市在高铁开通后将获得更大的旅游发展动能,并加快哈大高铁旅游带的形成。沿线城市“一日游”和“两日游”受益明显,偏远城市则在“七日游”方面受益较多;东北旅游应以高铁为契机,精心开发沿线旅游精品线路,加快旅游一体化合作,打造东北旅游新形象。高铁使旅游市场空间分布上出现“极化效应”,提升旅游产业供求效率的同时,拉大了城市间旅游差距,不利于旅游产业协调性发展。今后应以高铁为核心完善快速交通干线布局,将更多旅游城市和旅游景点纳入高铁通勤圈。  相似文献   
6.
介绍了2011年中国科学院新疆天文台南山站GPS和25m VLBI天线的归心测量方案、局域三角测量网、高程控制网与靶标交会测量方法及资料解算。利用测量数据,首次建立了南山GPS与VLBI空间大地测量技术并置站本地连接参数,测量精度优于1mm。  相似文献   
7.
孙中原  李永树 《测绘工程》2012,21(4):78-81,96
介绍我国的土地储备机制,针对土地储备管理工作中面临的数据分析过程繁琐、储备数量决策缺乏依据等问题,基于MapGIS K9平台完成了土地储备信息系统的设计与开发,实现土地储备数据库的动态管理、储备数量预测等功能,有效提高土地收购储备工作效率,并为土地储备科学决策提供参考依据。  相似文献   
8.
Future management of aquifer recharge   总被引:1,自引:3,他引:1  
  相似文献   
9.
A 5-year aquifer storage and recovery trial at Andrews Farm in South Australia involving the injection of more than 250 ML (250,000 m3) of fresh but turbid stormwater into a brackish limestone aquifer over 4 years and recovery of 150 ML in the fifth provided the opportunity to evaluate rates of clogging and unclogging and the potential to recover water suitable for irrigation supplies. Results reveal there is some clogging by injected sediment, but only to a relatively small degree considering the high suspended solid concentrations and moderate aquifer transmissivity. This clogging was offset by increased matrix porosity through calcite dissolution and by routine well redevelopments after each 40 ML of injection. No significant microbial clogging occurred. Breakthrough responses at three observation wells and the proportion of injectant in the recovered water were determined from chloride data. Temperature and caliper profiles clearly indicate the heterogeneous nature of the aquifer that is attributed, in part, to sand removal during the initial well development. The recovery efficiency was greater than 60%. The trial demonstrates that urban stormwater containing high and variable particulate levels, which receives only passive pre-treatment and is not disinfected, can be used to freshen a heterogeneous brackish aquifer to create a useful water resource.  相似文献   
10.
发展中地区银行业空间系统变化--以河南省为例   总被引:21,自引:0,他引:21  
基于对中国发展中地区的河南省的第一手调查数据,对经济水平较低、受外部影响较小但增长迅速的内陆省份银行业空间系统变化进行了量化分析和解释。结果表明,与国际上发达国家相同,中国发展中地区的国有银行业逐步向中心城市集中。其中,作为区域中心的地级城市的地位上升最为突出。其形成原因主要与制度变化有关;而区域经济的发展差异,又是促进该趋势的直接诱因。这一观点通过混合OLS模型模拟得到证明。城市内部的银行业区位变化,具有一些与发达国家的不同之处。区域经济快速发展带来了中心城市的迅速拓展。同时经济结构调整,又带来了城市内不同地区经济发展水平的变化。由此形成了银行业区位的不断扩散,新兴快速增长的地区,迅速吸引了一批银行的建立。对郑州市58家银行网点的调查表明,在1978年之前,银行网点设立十分遵循计划体制的安排;而在1979年以后,邻近地段“人均收入水平高:决定着相当一部分银行网点的布局。这从微观角度佐证了河南省的分析结论。金融系统的集中格局,为非中心地区经济发展带来的不利影响,应该给予关注。  相似文献   
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