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251.
基于RS和GIS技术下城镇空间变化分析及应用研究 总被引:16,自引:7,他引:16
城镇空间变化分析,是城镇发展趋势分析的基础,对城镇远景规划有十分重要的指导作用。它也是区域生态环境演变调控研究的重点内容和基础内容。本文将引用RS和GIS技术方法对城镇空间变化进行研究。其基本思路是,利用RS的TM卫片数据进行宏观监测,再利用GIS的空间分析功能,方便地进行城镇分布状况和迁移变化的空间分析与评价。该技术方法已被成功地应用于新疆城镇分布状况及动态变化研究项目中,收到较好效果。 相似文献
252.
From Rural Dilution to Multifunctional Countryside: Some pointers to the future from South Australia 总被引:1,自引:0,他引:1
Peter J. Smailes 《The Australian geographer》2002,33(1):79-95
Rural dilution, a term originally used in the UK in the 1950s, refers to change in the social composition of rural populations: those elements engaged in primary production (and its necessary servicing) are thinned out by agricultural restructuring and labour shedding, while at the same time in-migration of new elements (retirement, long-distance commuting, lifestyle migration) is occurring. The extent to which such dilution occurs is influenced by a number of factors, including distance in travel time from the nearest metropolitan or other large city, location with respect to the coast/perceived environmental amenity, and rural population density. This paper explores changes in traditional rural communities in Southern Yorke Peninsula, South Australia, which lie 2½-3 hours' drive from Adelaide and have been subject to substantial rural dilution. Drawing on two detailed surveys of the strictly rural (dispersed) population of the region carried out in 1984 and replicated in 2000, some important social impacts of the recent migration flows are identified, including changes in perceived community identity and allegiance, shopping and business patterns, and the very recent impact of the uptake of electronic communication innovations. The paper concludes with an assessment of the extent to which the trends identified are likely to continue, and mould future communities in similar distance and amenity situations over the next 10-20 years, changing the nature of rurality in Australia. 相似文献
253.
文章从以下 6个方面概要介绍了IGBP、IHDP与WCRP的一项新的联合计划———“全球环境变化与食物系统 (GECAFS)”的科学框架与实施战略 :(1)背景 ;(2 )GECAFS的概念框架 ;(3)GECAFS的科学主题 ;(4 )GECAFS的研究类型与“示范性项目” ;(5 )科学新领域 ;(6 )GECAFS计划与其它组织的资助关系及战略伙伴关系。 相似文献
254.
Sebastian Oberthür 《Climate Policy》2003,3(3):191-205
In response to Article 2.2 of the Kyoto Protocol, the International Maritime Organisation (IMO) and the International Civil Aviation Organisation (ICAO) have begun to consider greenhouse gas (GHG) emissions from international aviation and shipping. However, neither ICAO nor IMO have taken any effective action on the issue yet and progress can be characterised as slow. The lack of action has so far not been made up for by measures within the climate change regime or by individual countries. An important motivation for the efforts of ICAO and IMO so far has been the potential regulatory competition with the climate change regime. However, given the lack of political will to act on the issue within the latter, this motivation has not been very forceful. Against this backdrop, I argue that there are in particular three options for furthering progress within ICAO and IMO, namely (1) enhancing the threat of regulation of GHG emissions from international transport under the climate change regime; (2) undertaking unilateral domestic action by various countries (in particular the EU); and (3) furthering a learning process within ICAO and IMO. Furthermore, a closer coordination of efforts under ICAO, IMO and the climate change regime could facilitate and accelerate progress. 相似文献
255.
Atle Christer Christiansen 《Climate Policy》2003,3(4):343-358
The objective of this paper is to assess recent developments and prospects for future changes in United States (US) climate strategy. In doing so, the paper explores some of the key factors that have shaped strategies and policies to date, distinguishing between factors related to institutional and governance structures, linkages between science and policy, energy technology and the role of interest groups. Against this background, the paper attempts to explore future development paths for US climate policy. More specifically, the paper assesses opportunities for policy changes compared to the preferences of the current administration, and the prospects for future linkages between US and international climate change strategies. In brief, the paper argues that substantial changes are unlikely to take place in the near to medium term, leaving open, however, the possibility of wide-ranging changes in domestic politics or major incidents that could facilitate a shift in the perceived need for near-term action. 相似文献
256.
基于数字地球的全球变化研究 总被引:1,自引:0,他引:1
该文论述了全球变化研究和数字地球的特点及其内涵,重点分析了“数字地球”技术体系在全球变化研究过程的应用前景。在数字地球技术体系支持下,充分利用全球空间信息基础设施、3S技术、网络技术和虚拟现实等技术,不仅为全球变化研究提供强有力的理论和技术支撑框架,而且将极大地促进全球变化学科的飞速发展。 相似文献
257.
通过对 1 5年以来的流动重力重复测量资料的统计分析 ,认为在 MS5.0左右及大于 MS5.0地震前重力资料有显著的前兆异常。异常识别判据定为相邻两期段差变化绝对值大于、等于 40× 1 0 -8m· s-2 。预报指标 :发震时间为测出异常后 1 2 (± 6)个月内 ;地点在异常测段周围 1 50 km(特殊地质构造关系 2 50 km)范围内 ;震级一般为 MS5.0左右 (异常量大于 70× 1 0 -8m· s-2 时为 5— 6级 )。预报效能评价为 66.1 3%。 相似文献
258.
Drawing on results of a 2003 survey of environmental officers in every Local Authority (LA) in England and Wales, this paper assesses the reception and response of local government to the information being provided through the UK Climate Change Programme. Over three quarters of respondents (n=184) felt they did not have access to the best information about the impacts of climate change on their areas. Although up-to-date information is freely available from a number of official Government sources, those official sources are not consulted as consistently as the media or as intensively as the internet, despite being consistently regarded as much more accurate, credible, and appropriate to LA needs. We interpret this apparent contradiction between LA officer confidence in official sources and their relatively infrequent use as a consequence, first, of technical–cognitive and practical–temporal difficulties accessing and understanding official sources of climate change information and, second, of concerns about the practical relevance of that information for the administrative functions of local government and thus for any meaningful response by LAs to climate change. Our survey recorded considerable levels of stress, cynicism, and futility among LA officials that not only complicate communication efforts but also call into question the central assumption of the UK Climate Change Programme that simply making more locally specific information about climate change impacts available will motivate appropriate action. 相似文献
259.
IPCC第二次气候变化科学评估报告的主要科学成果和问题 总被引:14,自引:0,他引:14
介绍了政府间气候变化委员会(IPCC)最近出版的第二次气候变化科学评估报告中的主要科学成果,并说明了今后3~4年中IPCC从科学上主要关注的问题。 相似文献
260.
潮汐站资料分析表明香港地区海平面每年以1mm的速度上升。然而,在沿海填海地区,由于受长期地面沉陷的影响,下沉速度超过上升速度,导致海平面明显相对上升。受大规模地面沉陷的影响。填海区在台风暴潮期间极易受海水浸淹。为了有助于未来海岸的开发,建议利用现有技术水平的测量方法,包括卫星测高和激光测距方法等,对填海区进行长期连续的地面沉陷监测。对下沉问题提出预警,以便采取措施,如修筑海提,建抽水站等,以抵御海 相似文献