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1.
上海城市土地利用形成、变化及其空间作用机制   总被引:8,自引:1,他引:7  
基于多时段TM遥感影象资料,对上海地区近10年来城市土地利用变化类型、形成过程和相关空间机制进行了研究,结果表明:①农业用地是全区近10年来城市用地扩展的主要来源;②灌草丛与弃耕地作为一类独特的“中间过渡”土地利用类型,其数量、分布在一定程度上指示着新开发区形成、扩展的强度和方位;③具有较大面积、较少转变次数的土地利用变化类型,其空间格局强度最为显著,空间凝集度和亲和性也最强,构成区域城市化扩展的主体骨架。在此基础上,以具有较大规模的多个扩展核(常构成城市的CBD)为核心的“多核扩展”和以卫星城、交通干线周围为主的“点—轴扩展”模式,成为本区域城市化过程中城市形态组建和扩展的主要形式;④上海中心城区及其他主要城镇城市化过程中土地利用效率和集约化程度较高,以中、小城镇为主的城市化扩展过程则往往经历了较多的土地利用转变方式及其过程,城市化过程中土地集约化使用程度低,城市化土地利用扩展过程显得零散,规律性、可解释性较差。  相似文献   

2.
江苏省开发区土地集约利用潜力研究   总被引:7,自引:0,他引:7  
开发区是土地利用的重要方式,特别是在促进土地集约利用方面起到了良好的示范和辐射作用。本文基于江苏省开发区典型调查的基础上,分析和测算了全省开发区土地集约利用的理论潜力,并结合江苏省资源禀赋特点和经济发展的制约因素剖析了理论潜力实现的可能性及途径。结果表明,江苏省开发区2010年和2020年的土地集约利用理论潜力分别为261km^2和1069km^2;若能在劳动生产率和工业用地容积率等方面有所作为的话,江苏省开发区2010年和2020年的土地集约利用现实潜力将分别达210km^2和869km^2。这主要通过注重开发区投资主体的多元化、软硬件环境的不断完善和提高开发区的用地门槛来实现。  相似文献   

3.
面对当前我国经济开发区发展所面临的主要挑战,无论从自身经济增长规律出发.还是应对外部竞争压力,在新形势下,信息化是实现开发区产业升级与可持续发展的必由之路。如何针对开发区实际状况,系统、科学地进行信息化建设,包括大力发展信息产业并使其成为支柱产业,开创新经济增长点;以信息技术改造传统产业,促进产业升级与结构调整;以电子政务提高政府管理水平与服务效率、以电子商务提高企业的经营绩效与创新能力;以信息化推动城市化进程,提高人口素质与生活水平等。针对上述议题,特提出以“数字城市”建设、完善信息产业链为核心的开发区信息化发展战略。  相似文献   

4.
从精明增长的视角看浙江省城镇空间扩展的理性选择   总被引:3,自引:1,他引:2  
国内对于精明增长的研究多集中于宏观层面,区域探讨较少。浙江省社会经济发展引人关注,近年来被称为“浙江现象”。本文从区域层面——浙江省入手,在分析城市发展背景与“精明增长”差异的基础上,找出共同点,然后对城市空间扩展的现状及存在的问题进行深入剖析,以期能够在“精明增长”的框架下对城市发展深入思考。研究表明:浙江省目前的城市空间扩展迅速。资源要素低效利用,沿交通干线的轴向扩展呈现无序特征,并且机动化(小汽车普及)的趋势进一步加剧了用地空间的松散。但鉴于中西方城市应用背景的差异,“精明增长”并不能够简单地“复制”到浙江省,应根据实际,从思想和实践两个层面进行创新。具体来说,一是紧凑式开发与填充式发展相结合,提高土地产出效益;二是有机结合土地利用规划与交通系统规划,倡导公交先行;三是运用逆向思维设定城市增长边界。  相似文献   

5.
江苏省级开发区土地开发效益评价   总被引:1,自引:0,他引:1  
土地问题是当前我国开发区发展面临的重大挑战,在科学发展观指导下,国家从政策和管理层面对开发区提出提高土地集约利用水平的客观要求。江苏省是我国开发区较为发达的地区,开发区的发展对地区经济的发展起了重要推动作用,但也存在数量过多、土地利用集约度不高的问题。借鉴一些学者的相关研究,构建了一套开发区土地利用经济评价指标体系,采用系统协调度模型,对江苏省的省级开发区的土地开发效益进行评价,并就开发区效益评价结果进行了数学和空间分析说明。  相似文献   

6.
对开发区进行环境影响评价是开发区可持续发展的需要。大气作为环境的重要要素,其状况优劣对开发区的发展及布局都产生较大的影响,因而大气环境影响评价是环境影响评价体系中不可缺少的组成部分。如何进行开发区的大气环境影响评价,国内已取得了不少经验,但仍在探索之中。对城市开发区大气环境影响评价的内容和方法进行了探讨;以扬州市经济技术开发区为例,进行了分析、预测和评价,对环境评价中的公众参与环节进行了有益的探索与尝试;对开发区进行了大气功能区划分,给出了开发区大气主要污染物总量控制方案;最后,针对扬州市经济技术开发区的实情,在产业发展方向、项目规划布局、能源使用、绿化、环境管理以及土地管理等方面提出了环境保护的对策和建议。  相似文献   

7.
我国开发区土地资源配置效率的区域差异研究   总被引:11,自引:0,他引:11  
应用比较优势理论,以国家级53个经济技术开发区为例。研究了不同区域间开发区土地利用的比较优势。结果表明。按照区域土地利用的比较优势来配置土地资源能够提高土地利用的总福利水平。整体上.中西部国家级开发区的比较优势高于东部地区:而区域内部东部地区的京津苏沪及中西部地区的中心城市在开发区建设用地的利用上具有比较优势。因此,按照开发区土地利用的比较优势度计算结果,在排除开发区自身发育不完善和管理层面因素后,对于确实不适宜进行开发区工业建设的应进行空间布局的调整,恢复其农业生产;而对于比较优势度较高的地区可根据实际需要增设相应的开发区。以实现耕地保护与开发区建设的双赢。  相似文献   

8.
基于新经济地理学相关理论,针对江苏省沿江开发战略实施以后,制造业空间可能存在的变动,在整理和分析调查问卷资料的基础上,选择专业化指数和基尼系数2种方法来定量分析江苏省21个沿江省级以上开发区空间分工、制造业集聚和转移态势。结果表明:(1)2002~2006年江南沿江开发区通过向江北沿江开发区转移部分传统产业,逐渐形成了江南沿江技术/资本密集型制造业“中心”和江北沿江劳动密集型制造业“外围”的空间分工格局;(2)江南沿江开发区内部、江北沿江开发区内部尚未形成良好的分工关系;(3)受开发区发展阶段、区域产业政策、本地化资源供给和市场需求等因素影响,并未发现理论预期的普遍存在的产业集聚现象,仅纺织服装、石化、电力、塑料橡胶等产业呈现集中趋势.  相似文献   

9.
以无锡市区5个省级开发区为研究对象,基于抽样调查资料,从土地利用结构、土地利用强度和投入产出等方面分析了无锡市区省级开发区土地利用现状,对不同行业土地集约利用状况进行了定量评价。结果显示:电气机械及器材制造业土地集约利用水平较高,在08以上;交通运输设备制造业、通用设备制造业和通信设备、计算机及其他电子设备制造业的土地集约利用水平在075以上;橡胶制品业的综合集约度在07以上;其次是专用设备制造业和仪器仪表及文化、办公用机械制造业,为06以上;塑料制品业、金属制品业、纺织业和化学原料及化学制品制造业的土地集约利用水平相对较低,不到06。要合理控制开发区规模,不断提高开发区的经济效益;对新进项目设置明确的入园门槛,加大开发区内部的空间挖潜力度;完善土地利用的管理机制,严格开发区内工业用地的招拍挂出让制度。建立集约用地的考核制度,加强对集约用地的监督  相似文献   

10.
改革开放以来,随着苏南地区经济高速发展,工业化及城市化进程加快,导致建设用地急剧扩张。为了研究苏南建设用地扩展类型,基于1980~2010年建设用地数据,利用ArcGIS 93软件识别并提取了3种建设用地扩展类型:填充型、边缘增长型和跳跃型,并分析了建设用地扩展类型景观格局时空动态及其驱动力。结果表明:1980~2010年,苏南地区的建设用地面积增加了44582%,其中1980~2005年增加了16373%;2005~2010年增加了10696%,常州市建设用地的扩展速率最大,为75286%。1980~2005年,苏南地区边缘增长型占据了7403%,其次是跳跃型与填充型,而2005~2010年,建设用地扩展类型的比重仍与1980~2005时段相一致,但变化更为剧烈。建设用地扩展类型的斑块个数均处于增加趋势,3种扩展类型的形状区域复杂,建设用地扩张景观类型破碎化严重但其链接度仍较高。苏南5市的填充型扩展类型主要集中于城市中心附近,而跳跃型主要分布于远离城市的区域。苏南地区经济快速发展、人口增加、工业化进程、房地产投资、外资直接投资、固定资产投资都在影响着建设用地的扩展  相似文献   

11.
Integration of indigenous knowledge and ethnoscientific approaches into contemporary frameworks for conservation and sustainable management of natural resources will become increasingly important in policies on an international and national level, both in countries that are industrialised and those that have a developing status. We set the scene on how this can be done by exploring the key conditions and dimensions of a dialogue between ȁ8ontologiesȁ9 and the roles, which ethnosciences could play in this process. First, the roles of ethnosciences in the context of sustainable development were analysed, placing emphasis on the implications arising when western sciences aspire to relate to indigenous forms of␣knowledge. Secondly, the contributions of ethnosciences to such an ȁ8inter- ontological dialogueȁ9 were explored, based on an ethnoecological study of the encounter of sciences and indigenous knowledge in the Andes of Bolivia, and reviewed experiences from mangrove systems in Kenya, India and Sri Lanka, and from case-studies in other ecosystems world-wide, incl. Australia, Burkina Faso, Ecuador, Ethiopia, Guatemala, Indonesia, Nepal, Niger, Philippines, Senegal, South-Africa and Tanzania.  相似文献   

12.
We review studies of the effects of low ambient ozone concentrations on morbidity that found a negative coefficient for ozone concentration. We call this a Paradoxical Ozone Association (POA). All studies were in regions with methyl ether in gasoline. All but one study carefully controlled for the effects of other criterion pollutants, so the phenomenon cannot be attributed to them. One was in southern California in mid-summer when ozone levels are highest. Because ozone is created by sunlight, the most plausible explanation for a POA would be an ambient pollutant that is rapidly destroyed by sunlight, such as methyl nitrite (MN). A previously published model of engine exhaust chemistry suggested methyl ether in the fuel will create MN in the exhaust. MN is known to be highly toxic, and closely related alkyl nitrites are known to induce respiratory sensitivity in humans. Support for the interpretation comes from many studies, including three linking asthma symptoms to methyl tertiary butyl ether (MTBE) and the observation that a POA has not been seen in regions without ether in gasoline. We also note that studies in southern California show a historical trend from more significant to less significant ozone-health associations. The timing of those changes is consistent with the known timing of the introduction of gasoline oxygenated with MTBE in that region.  相似文献   

13.
湘鄂赣地理位置优越,农业资源丰富,稻谷、茶叶、麻类、棉花、油料、柑桔和淡水产品、禽蛋、肉类等在我国居有重要的地位,因此,大力发展三省农业生产,对我国人民实现小康生活具有战略意义。今后,要加速专业化区域化进程。我们找出生产潜力所在:改造低产田、低产园、低产水面;开发“三高”技术;开垦荒地、荒山、荒水;适当提高复种指数。通过建设,三省主要农产品将自给有余,还可满足国内外市场的需要。努力方向:高效农业开发——综合农业开发,吨粮田开发,玉米带开发,饲料稻开发,山区开发;合理布局农业生产;深化农业商品基地建设,发展综合利用,搞活商品流通;全面提高农业现代化水平,加强农业社会服务体系。  相似文献   

14.
The use of quantitative data for constructing prognostic maps of the dynamics of ecosystem degradation and restoration by nonlinear simulation methods is a topical field of landscape ecology. This method of dynamic cartography is based on fiberwise comparison of data on the state of Chernye Zemli (the Kalmyk Republic, Russia) in different years and the detailed analysis of the period on which the prognosis was based. For this purpose, materials of repeated aerial and satellite photography obtained during a long period (1954–1993) were used. Comparison of maps characterizing the dynamics of Chernye Zemli between 1958 and 1993 allows prognostic electronic maps for the next 10–15 years (with a five-year interval) to be drawn and land prognosis for the next 20–30 years (1998–2023) to be obtained. Deceased  相似文献   

15.
Information regarding the distribution of volatile organic compound (VOC) concentrations and exposures is scarce, and there have been few, if any, studies using population-based samples from which representative estimates can be derived. This study characterizes distributions of personal exposures to ten different VOCs in the U.S. measured in the 1999-2000 National Health and Nutrition Examination Survey (NHANES). Personal VOC exposures were collected for 669 individuals over 2-3 days, and measurements were weighted to derive national-level statistics. Four common exposure sources were identified using factor analyses: gasoline vapor and vehicle exhaust, methyl tert-butyl ether (MBTE) as a gasoline additive, tap water disinfection products, and household cleaning products. Benzene, toluene, ethyl benzene, xylenes chloroform, and tetrachloroethene were fit to log-normal distributions with reasonably good agreement to observations. 1,4-Dichlorobenzene and trichloroethene were fit to Pareto distributions, and MTBE to Weibull distribution, but agreement was poor. However, distributions that attempt to match all of the VOC exposure data can lead to incorrect conclusions regarding the level and frequency of the higher exposures. Maximum Gumbel distributions gave generally good fits to extrema, however, they could not fully represent the highest exposures of the NHANES measurements. The analysis suggests that complete models for the distribution of VOC exposures require an approach that combines standard and extreme value distributions, and that carefully identifies outliers. This is the first study to provide national-level and representative statistics regarding the VOC exposures, and its results have important implications for risk assessment and probabilistic analyses.  相似文献   

16.
The Eastern Mediterranean region is among the regions which were predicted to become drier under IPCC climate scenarios. Here, we document a gradual reduction of rainfall and tree growth and the loss of rural springs during the last decades of the twentieth century. Years with severe drought are associated with very low tree growth (dendrochronology) and dry falling of springs as evidenced by interviews with local stakeholders. The paper discusses the consequences of accelerating drought on natural vegetation and agriculture and points at the interaction with fire dynamics and economy, both likely to enhance the drought effect.  相似文献   

17.
Variation in the reproduction of Varroa jacobsoni mite was studied in relation to the expansion of the range of its parasitism on the honeybee. Geographic differences in the seasonal dynamics of mite reproduction in the nests of bee families were revealed. Variation in the sex ratio of mites and the factors inhibiting their reproduction at the northern boundary of the honeybee range are considered. The forms of parthenogenetic reproduction in V. jacobsoni are discussed.  相似文献   

18.
The effect of long-term exposure to natural excretions of the European polecat on the morphological parameters and hormonal status of adult male Campbell hamsters (Phodopus campbelli) and dwarf hamsters (Ph. sungorus) was studied. Exposure to volatile components of natural excreta of a potential predator did not have any significant effect on hamsters. The combined influence of volatile and nonvolatile components of the polecat’s excretions caused physiological stress in Ph. campbelli, while in Ph. sungorus, on the contrary, an increase in thymus weight and the plasma testosterone level was recorded.  相似文献   

19.
The use of experimental settings to observe human behaviour in a controlled environment of incentives, rules and institutions, has been widely used by the behavioural sciences for sometime now, particularly by psychology and economics. In most cases the subjects are college students recruited for one to two hour decision making exercises in which, depending on their choices, they earn cash averaging US$ 20. In such exercises players face a set of feasible actions, rules and incentives (payoffs) involving different forms of social exchange with other people, and that in most cases involve some kind of externalities with incomplete contracts, such as in the case of common-pool resources situations. Depending on the ecological and institutional settings, the resource users face a set of feasible levels of extraction, a set of rules regarding the control or monitoring of individual use, and sometimes ways of imposing material or non-material costs or rewards to those breaking or following the rules. We brought the experimental lab to the field and invited about two hundred users of natural resources in three Colombian rural villages to participate in such decision making exercises and through these and other research instruments we learned about the ways they solve - or fail to - tragedies of the commons with different social institutions. Further, bringing the lab to the field allowed us to explore some of the limitations of existing models about human behaviour and its consequences for designing policies for conserving ecosystems and improving social welfare.  相似文献   

20.
The size of shells in some freshwater pulmonate mollusk species abundant in Western Siberia (Lymnaea fragilis, L. terebra, Planorbis planorbis, and Anisus leucostoma) is relatively large in the south and decreases in the north. It is supposed that this phenomenon is explained by the fact that the season with conditions allowing the growth of mollusks is shorter in the north than in the south of Western Siberia.  相似文献   

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