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1.
长江经济带城镇化的发展为工业化提供了强劲动力,但同时工业用水的猛增促使水资源供需矛盾更加尖锐以及水环境污染愈发严重。通过建立工业用水与城镇化之间的脱钩模型,利用“十一五”和“十二五”时期的面板数据,研究长江经济带各省市工业用水与城镇化的脱钩状态,并在此基础上借助对数迪氏指数法考察工业用水量的具体影响因素。研究发现:(1)2006~2015年长江经济带城镇化对工业用水总体呈现脱钩状态,但“十一五”期间表现为弱脱钩状态,而“十二五”期间表现为强脱钩状态;(2)长江经济带各省市脱钩关系存在较大的时空差异,长江三角洲经济区、长江中游经济区以及长江上游经济区明显处于不同的脱钩状态;(3)城镇化影响工业用水的四大效应中,技术效应抑制工业耗水,产出效应则促进工业耗水,而结构效应和人口效应对工业用水的影响随时空变化而变化。据此,提出通过技术节水提高工业用水的利用效率,因地制宜促进区域平衡发展等建议。 关键词: 城镇化;工业用水;脱钩模型;LMDI模型;长江经济带  相似文献   

2.
Water quality criteria, as a means of distinguishing "good" water from "bad" water, have been employed for over 150 years. During the 1940s and 1950s, the formulation of water quality criteria and their role in water quality management were hotly debated in the United States as each state formulated its own approach to water pollution control. In 1965, when the federal government assumed control of water quality management in the US, a single, national approach to the formulation and use of criteria had to be selected and implemented nationwide. The purpose of this paper is to briefly review the history of criteria as a basis for water quality management in the US; note the different water quality management philosophies used by states prior to 1965; and summarize the relationship of criteria to monitoring over the past 30 years. Standards, as legal instruments, are developed for a specific water body by designating a use of the water (society value) and the criteria necessary to protect the use (a scientific finding). Standard violation, as a concept, tends to remain as a single-sample exercise (i.e., the sample measurement is either above or below the standard). Increasingly, however, there is a demand to classify large bodies of water (e.g., lake, river segment, or aquifer), over a set time period, such as a day, year, or decade, as either in compliance or in violation of water quality standards. No peer-reviewed, standardized method for computing standard "violations" has been widely accepted for this purpose. The paper ends with a call to develop such methods, if water quality managers must produce standard violation information (infer sample results) over time and space. Electronic Publication  相似文献   

3.
为了遏制长沙市城市的无序扩张,促进土地节约集约、高效利用,保障生态空间质量,划定长沙市城市开发边界成为重要举措。基于居民活动空间扩展,选取人口密度、居民活动分布、基础设施布局等多源时空数据,通过量化居民活动空间扩展概率,并利用植被覆盖度构建生态约束强度,确定二者协调规则,作为CA模型的约束条件,进行城市建设用地模拟,划定城市开发边界。结果表明:划定的长沙市城市开发边界,结果与长沙市“十三五”规划的城市空间发展框架基本一致,对未来建设用地扩展方向预测合理,而且避免了侵占重要生态资源,达到了兼顾城市空间发展和生态资源保护的多重目的。  相似文献   

4.
Refining the ecological footprint   总被引:8,自引:0,他引:8  
Ecological footprint measures how much of the biosphere’s annual regenerative capacity is required to renew the natural resources used by a defined population in a given year. Ecological footprint analysis (EFA) compares the footprint with biocapacity. When a population’s footprint is greater than biocapacity it is reported to be engaging in ecological overshoot. Recent estimates show that humanity’s footprint exceeds Earth’s biocapacity by 23%. Despite increasing popularity of EFA, definitional, theoretical, and methodological issues hinder more widespread scientific acceptance and use in policy settings. Of particular concern is how EFA is defined and what it actually measures, exclusion of open oceans and less productive lands from biocapacity accounts, failure to allocate space for other species, use of agricultural productivity potential as the basis for equivalence factors (EQF), how the global carbon budget is allocated, and failure to capture unsustainable use of aquatic or terrestrial ecosystems. This article clarifies the definition of EFA and proposes several methodological and theoretical refinements. Our new approach includes the entire surface of the Earth in biocapacity, allocates space for other species, changes the basis of EQF to net primary productivity (NPP), reallocates the carbon budget, and reports carbon sequestration biocapacity. We apply the new approach to footprint accounts for 138 countries and compare our results with output from the standard model. We find humanity’s global footprint and ecological overshoot to be substantially greater, and suggest the new approach is an important step toward making EFA a more accurate and meaningful sustainability assessment tool.
Jason VenetoulisEmail:
  相似文献   

5.
认知快速城镇化背景下城市空间生产、生活和生态功能的变化规律既是人文-经济地理学研究的重要内容,也是城市国土空间开发及其格局优化的内在依据。以长沙都市区为实证区,以遥感影像、城市土地利用调查数据等为主要数据源,选取2000、2009、2016年为研究时间节点,基于土地主体功能的差异构建“三生”功能评价体系,采用空间自相关、冷热点分析和样带分析等方法,探究长沙市“三生”功能的变化特征并提出调控路径。结果表明:(1)长沙都市区整体的生产、生活功能持续强化,但生态功能有所减弱;(2)长沙都市区内部“三生”功能强弱亦发生变化,不同功能空间重组,“三生” 功能的均衡性提高;(3)长沙都市区“三生”综合功能水平持续提升,高水平区域逐渐向城市中心集聚,呈现单核集聚→单核集聚-多核分散→网络均衡化的城市功能空间结构发展模式,但“三生”功能空间单元变化模式各异;(4)应从“三生”功能用地结构的“质”与“量”两方面对长沙都市区空间格局进行综合调控。  相似文献   

6.
农户宅基地使用权退出价格形成机制探究   总被引:1,自引:0,他引:1  
农户宅基地使用权有偿退出是中国宅基地产权制度改革的基本方向,使用权退出价格形成机制是推进这一改革的主要难题。本文按照产权结构变化与使用权退出用途不同两个标准,将农户宅基地使用权退出划分为部分-公益、部分-经营、完全-公益、完全-经营四种理想类型,分析了不同退出类型的现行价格形成机制及其缺陷。初步研究发现:以耕地产值为标准的政府征地指导价是目前农户退出宅基地使用权的主要价格标准,它以低于耕地的价格标准征收农户宅基地,未能体现此类土地使用权的稀缺性;集体议价在经营性征地中剥夺了少数人的自由交易权;市场议价的合法空间狭窄。基于这些问题,文章按照国有土地与集体建设用地"同地、同权、同价"的原则,重新设计了一个以基准地价为标准的农户宅基地使用权退出价格形成模型。模型应用与案例比较发现,与耕地产值标准相比较,基准地价标准显示出良好的适用性与可行性:它同时考虑了供需关系、产权结构和政策干预等因素,在农户宅基地使用权不同退出情形中,均显著提升了土地使用权的转让价格,体现了宅基土地资源的稀缺性与产权转让的公平性,显示了公益性用地与经营性用地的差异,兼顾了政府、集体与个人收益。本文建议,在立法方面,修正《土地管理法》中以耕地产值标准作为征用农村建设用地参照标准的做法,改用基准地价标准;在模型运用方面,以地方政府公布基准地价的40%作为宅基地使用权转让估值标准的底线,经济发展水平较高、土地开发状况较好、土地市场活跃的地方,可以适度提高这一比例。  相似文献   

7.
我国耕地资源数量安全的时空差异分析   总被引:6,自引:0,他引:6  
耕地资源数量安全是耕地资源安全非常重要的组成部分,它受到资源禀赋、经济发展水平、管理和政策等因素的影响。本文在分析耕地资源数量安全影响因素的基础上,构建其评价指标体系,并对我国耕地资源数量安全的时空差异规律进行了分析,结果表明。自改革开放以来,我国耕地资源数量安全状况呈先增后减的变化趋势;从安全水平的区域分布来看,北部和西部省份的安全水平普遍高于东部和南部省份,同时发现,区域安全水平与经济发展水平呈负相关关系。  相似文献   

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9.
随着人口增长和城市化程度越来越高,作为城市土地利用类型之一的公共绿地往往最容易被改变性质和用途。开展城市公共绿地价值评估,是当前城市规划、绿地保护与建设中迫切需要解决的问题。通过梳理西部城市群中典型的甘青宁3个省会城市的公共绿地存在的主要问题,并采用CVM调查法评估城市公共绿地的服务价值。研究表明:兰州市城市公共绿地提供的生态服务总价值约为 3 324~3 761 万元之间,西宁、银川两市因城市规模相对较小,城市公共绿地提供的生态服务总价值较兰州市略低;分析社会因素对支付意愿的影响,得出职业、收入、性别等变量对支付意愿的正向影响作用较大;比较单位公共绿地面积的生态服务价值产出可以发现,兰州市单位公共绿地面积的生态服务价值产出最高约为1.57~1.77元/m2,兰州市城市公共绿地的生态服务价值产出效率较高。  相似文献   

10.
The influence of intra- and interspecific competition of common and East European voles on their daily activity was studied in 34-m2 enclosures at the Chernogolovka Experimental Research Station (Moscow Region). Family groups of animals captured in the same biotopes were placed in enclosures and, 25 day later, their daily activity was observed. Thereafter, the animals were pooled and observations were repeated 25 days later. The experiment consisted of three stages. At the first stage, the daily activity, time budget, and social behavior of common voles were studied before and after pooling different family groups; at the second stage, the same was performed with East European voles; and at the third stage, with both species. The species proved to use different strategies for alleviating intraspecific competition: in common voles, this was segregation of ecological niches via desynchronization of daily activity; in East European voles, conversely, aggregation in groups and synchronization of activity. Under experimental cohabitation, the strategy of the common vole, a more aggressive species, was to force out the other species, ecologically similar but less competitive; the strategy of the East European vole was aimed at avoidance via segregation of ecological niches in time.  相似文献   

11.
A method for determining the specific alpha activity of thick sources using a large area ZnS(Ag) scintillation detector is presented. In this method a quadratic relationship between the detector response and window thickness is assumed. This method provides a quick estimation of alpha activity in the sample, so it is an indicative method. The aim of this experimental work is to approve theoretical assumption and to develop a standard routine method for absolute alpha measurements of thick contaminated environmental sources. For this purpose reference material U(3)O(8) and spiked standards of soil were used. Measurements of contaminated soil samples from south Serbia showed the practical application of this method.  相似文献   

12.
1 INTRODUCTION Urban space is a widely used concept in our everyday life. Architects and planners have always been concerned with the spatial and social functions of urban space. This is because of the growing recognition that the way urban space is designed and planned may determine the functional efficiency for urban space use, including its sociability and its habitability. Efficiency is a function of urban space itself since it is concerned primarily with form and organization, that i…  相似文献   

13.
边缘化地区特征、形成机制与影响--以安徽省池州市为例   总被引:12,自引:0,他引:12  
边缘化地区是指在区域发展中,与核心地区的差距正在逐步拉大的地区。以安徽省池州市为例,分析其空间边缘化的主要表现,即区域社会经济发展缓慢、处于长江经济带的发展低谷,主要经济指标在全省的比重持续下降,居民生活水平和地方管理水平等方面均明显滞后于时代的发展,交通区位边缘性日益增强等。并对区域空间边缘化形成的主要机制进行探讨,认为空间过程缓慢是边缘化形成的历史基础,城镇体系发育不良是边缘化形成的空间因素,行政区划频繁变动是边缘化形成的人为因素,产业结构低级无序化是边缘化形成的经济原因等。区域空间边缘化对区域社会经济发展的负面影响主要表现为:空间边缘化与区域社会经济发展之间的恶性循环,空间结构不稳定性增强和无序化发展。  相似文献   

14.
Abstract

In this paper, a new method based on the space syntax is presented to optimize the urban space configuration. Space syntax theory is used to detect systematically whether one urban space configuration is optimal or not from four aspects including traffic space, cognition space, land use space and culture space. After introducing the computational and cognitive aspects of space syntax for the research of urban space, a framework of urban space optimization based on space syntax is proposed, then the integration with GIS and the extension to third dimension are discussed. Finally, a case study for Kanmen town of Zhejiang province of P.R.China is illustrated by using Axwoman tool.  相似文献   

15.
The history of the term station (in Russian, statsiya) in the Russian ecological and faunistic literature, interpretation of its meaning by different authors, and relationships between the terms station, habitat, biotope, and ecological license are discussed. It is suggested that station should be interpreted as the entire set of all external conditions affecting a population, which is observable as a part of physical space possessing certain properties.  相似文献   

16.
17.
标准地域单元划分是国土空间规划关于国土空间综合分区进行空间评价的基础。为了给国土空间规划编制提供更好的单元服务,在借鉴欧盟NUTS划分思路的基础上,提出了建立符合中国国情的省级国土空间规划基本评价单元模式——国土空间标准地域划分(NUTSP)理念,构建了标准地域单元划分的原则、依据和技术路线,并结合湖南省对省级尺度国土空间标准地域划分的具体实施途径进行了探讨。研究结果表明,根据NUTSP划分原则与方法,结合湖南省域内不同地域的地形地貌特征、资源禀赋差异、社会经济发展基础等因素,并与综合自然地理区划相衔接,对全省现有122个县级行政区划单元进行适当合并与拆分,重新划定135个国土空间标准地域单元,能从最大限度上满足未来全省国土空间规划对空间同质性与异质性的表达需求,对未来建立统一的空间规划体系和探索"多规合一"工作具有重要意义。  相似文献   

18.
山地是一种特殊的生态环境类型,受自然分异规律与人类经济活动的双重干预和影响,产生其特有的时空分异规律与层带组合格局。通过土地生态类型格局分析,可以揭示山地生态环境类型结构瑟功能的异质性和有序性,从而为探讨农业资源的时空性及其开发利用模式提供科学指导。  相似文献   

19.
城乡空间边界识别是区分城乡地域、划定城市增长边界的科学基础,城乡边界动态演化方法一直是地理学研究的重要内容之一。以南京市1985~2016年土地利用、二三产业增加值和人口密度数据为基础,选取景观紊乱度和建设用地占比为形态指标,二三产业增加值和人口密度为功能指标,从形态和功能两个维度构建城乡空间边界识别的指标体系,利用公里网格对各个指标进行切分后依据距离衰减理论和“断裂点”分析方法来识别南京市的不同阶段城乡边界及其演化过程。结果表明:(1)1985~2000年南京城市扩张以内部填充为主,城乡边界变化较为缓慢;2000~2016年城镇建设用地迅速扩张,城乡边界变化幅度较大;(2)南京市城乡空间边界在不同阶段呈现出不同的扩张特点,与不同发展阶段的发展模式密切相关,城市国有经济和乡村工业化阶段城乡边界变化较慢,快速城市化和开放型经济阶段城乡边界变化较快;(3)南京作为特大城市,城镇化及城乡融合发展水平较高,以南京为例检验城乡边界演化识别方法具有一定的代表性,也有利于为其他大都市区城乡空间边界识别提供参考借鉴。  相似文献   

20.
农用地流转是充分发挥土地利用效益,实现农业规模化生产和产业化经营的一种积极探索,采用参与式农户评估法,以重庆市典型区(县)为例,对农用地流转的影响因素进行了探讨。分析结果表明:缺乏规范的操作程序与农用地流转中介组织、缺乏完善的社会保障体系以及区位条件的差异是影响重庆地区农用地流转的主要因素。建立健全农用地流转相关政策和农村社会保障制度,加速城镇化进程和加强农村基础设施建设对重庆地区的农用地流转具有积极的推动作用。  相似文献   

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