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991.
The association between spatial patterns of retail activity and the spatial configuration of street networks was examined by means of the space syntax methodology in eight Israeli cities that represent two city types, characterized by different planning approaches and urban growth: (i) new towns, which were established according to a comprehensive city plan and modern planning concepts of “tree-like” hierarchical street networks and “neighborhood units”; (ii) older cities, where street networks and the spatial patterns of retail activity were formed incrementally during their growth. Unlike in older cities, retail activity in new towns concentrates in relatively less-accessible and intermediate locations. This is indicated by a weak correlation between retail activity and the street network’s Integration and Choice centrality measures. The comparison between Israeli cities illustrates the influence of urban growth and planning approaches on the formation of retail activity and its interaction with the structure of the street network.  相似文献   
992.
多因素耦合下三峡库区土地利用未来情景模拟   总被引:21,自引:3,他引:18  
邓华  邵景安  王金亮  高明  魏朝富 《地理学报》2016,71(11):1979-1997
模型模拟和情景变化分析是未来土地利用变化研究的核心内容,本文以2000年三峡库区土地利用现状为基期数据,利用Binary Logistic模型回归分析驱动因子与土地利用间的关系,利用CLUE-S模型对2010年土地利用进行模拟,校验并确定影响库区土地利用驱动因素的主要参数后,基于自然增长、粮食安全、移民建设和生态保护对2020年、2030年库区土地利用情景予以模拟。结果表明:① 通过Binary Logistic模型分析和检验,水田、旱地、林地、草地、建设用地和水域的ROC曲线下面积值均大于0.8,表明所选驱动因子对土地利用的解释能力较强,可用来估算土地利用概率分布;② 2010年各地类模拟结果经验证得Kappa系数分别为水田0.9、旱地0.92、林地0.97、草地0.84、建设用地0.85和水域0.77,总体上能满足模拟与预测需求;③ 多情景模拟显示库区不同土地利用类型在空间上的竞争关系,以及所带来的对库区粮食安全、移民建设、生态保护的影响,包括水田大量转换为旱地(“水改旱”)、耕地与林草地被建设占用、林草地开垦为耕地、陡坡耕地退为林草地等行为,需要在土地利用优化中平衡各方面的需求;④ 多因素、多情景模拟能为库区土地利用提供更为清晰的、可供抉择的政策调控思路。  相似文献   
993.
Land use and land cover (LULC) change in the Ganges-Brahmaputra delta (GBD) poses significant challenges towards future environmental sustainability of the region and requires regional scale monitoring of key bio-physical variables and changes in their inter-relationship over space and time. Focusing on the southern part of the lower GBD region along the international border of India and Bangladesh, this study examined the spatio-temporal variability of LULC change and its relationship with Land Surface Temperature (LST). Furthermore, LULC-LST relationships were compared between Indian and Bangladesh part and its trend in and around big cities (with more than 1 million population) and towns (with more than 100,000 population) was investigated. Results showed that LST changes were predominantly driven by LULC changes on both sides of the border. Urban growth is the dominant form of LULC change, and the rate of land change was faster in 2005–2010 time period than 1989–2005. Over the period of 21 years, mean January LST decreased by approximately 1.83 °C in Indian part and 1.85 °C in the Bangladesh part. Areas that changed from to rural from agricultural experienced decrease in mean LST, whereas those areas that changed to urban from either agriculture or rural, experienced increase in mean LST. The relationship between LULC and LST are same on both sides of the Indo-Bangladesh border. In bigger cities like Kolkata (in India) and Khulna (in Bangladesh), there is a high spatial variability in relationship between LULC and LST compared to large towns. The LULC-LST relationship in large towns in India was influenced by proximity to Kolkata and coastal areas, whereas in Bangladesh no such influence was evident. The results and the data produced in this study are crucial for monitoring LULC changes, for developing spatial decision support system, and thus will be helpful to address the current challenges of land management in the GBD region. Changes in the LULC and LST are important indicators of GBD's environmental health and access its vulnerability and thus the present findings serve as baseline information for future studies seeking to examine the impact of differential policies on the LULC change in the region.  相似文献   
994.
Special Economic Zones (SEZs) are important vectors of neoliberal globalization in India. Despite facing widespread resistance against the proposed land acquisition for these zones, they are still being promoted across the country. We argue that the wealth redistribution to the country's elites and the fractured resistance movements enable neoliberalism and its practices to grow in the countryside. Using a private sector SEZ in Gurgaon as a case study, this article explores how special economic zoning, as a neoliberal policy, has been implicated in the spatialized production of poverty. We also show that the main actors who promote neoliberalism in India (the state and the large‐scale urban private sector) have found a seemingly unlikely ally in rural India in the form of farmers with large landholdings, rural elites who are willing to let go of their land under certain conditions. The data for the article was collected in India in 2009–10.  相似文献   
995.
The environmental effects of disease are broadly recognized but still not fully understood. The impact of health on economic development has been well-documented, as have how changes in land cover can contribute to poor health. However, little is known about how changes in health may impact land use and land cover. Fallowing has long been regarded as an advanced, sustainable land use decision employed by subsistence agriculturalists. In the presence of a prolonged illness, however, subsistence agriculturalists may also potentially use fallowing as a coping mechanism. In this paper we seek to understand the extent to which fallowing is used as a coping strategy by households facing a prolonged illness. If illness threatens a household's labor supply, it could affect their ability to cultivate all of their land and may impact food security and general economic well-being. Additionally, it may also impact the actual landscape, as previously agricultural land may revert to a transitional state or land abandonment. This study employs mixed methods to determine if unhealthy agricultural households use fallowing as a coping strategy, identifies whether or not unhealthy fallowing households are more vulnerable agriculturally and economically than their healthier fallowing counterparts, and examines whether there is a land cover effect that can be detected using Landsat TM/ETM + satellite imagery.  相似文献   
996.
珠江口湾区海岸线及沿岸土地利用变化遥感监测与分析   总被引:4,自引:1,他引:3  
王琎  吴志峰  李少英  王帅帅  张晓诗  高群 《地理科学》2016,36(12):1903-1911
利用遥感、GIS技术对珠江口湾区1960~2012年海岸线以及海岸带土地利用进行监测,通过定量化、空间化方法监测海岸线和土地利用的时空变化,并分析二者的关系,进而探究珠江口湾区海岸线变迁的原因。研究结果表明,1960~2012年,珠江口湾区海岸线长度由1 134.95 km增至1 508.02 km,在此期间,湾区新增的陆地面积为878.11 km2;从空间上看,广州、珠海及深圳市在珠江口五市中不仅海岸线增长幅度较显著,新增陆地面积也较大; 1960~2012年,珠江口湾区建设用地扩张幅度非常大,增长了33.05倍,城镇建设和农业发展等人类活动是52 a来珠江口湾区海岸线发生显著变化的重要原因。  相似文献   
997.
随着城市化与工业化程度不断加深,产业空间结构不断重组,导致土地供需矛盾日益突出,国土资源无序开发日益严重,因而优化国土资源空间格局,成为生态文明建设的首要任务。同时,科学合理配置土地资源对土地规划提出了更高要求,传统土地规划方法有待改革。在基于尊重自然、顺应自然的开发理念下,总结土地自然过程基础对土地规划的影响,实现“山水路林田生命共同体”的协调规划发展。其次,“大数据”时代的来临,云计算、空间数据整合、云分析等技术对土地规划方法提供新的技术支撑;最后,针对土地规划数据特殊性、移动用户终端的广泛性,提出应创建土地规划云服务平台,使土地规划实现数据集成管理和更新,从而提高土地规划质量。  相似文献   
998.
梁流涛  翟彬  樊鹏飞 《地理科学》2016,36(10):1522-1530
在农户土地利用引起的环境问题日益严重的背景下,如果农户土地利用效率的测度只考虑“好”产出,而忽略“非意欲”的环境产出,可能造成测度结果不准确。因此,将“非意欲”产出引入农户土地利用效率评价模型,利用河南省粮食生产核心区农户抽样调查数据测度环境因素约束下的农户土地利用效率,并探讨其效率状况及影响因素。主要的结论如下:调查区域环境因素约束下的农户土地利用效率平均值仅为0.612,效率值总体不高,有较大的提升空间。不同规模农户的土地利用效率差异较大,二者呈现“U型”变化趋势。环境因素约束下的农户土地利用效率的影响因素来自多个方面。其中,农户生计方式兼业化在一定程度上降低了环境约束下的农户土地利用效率;种植结构调整虽然能够增加农户农业收入,但不利于环境因素约束下的农户土地利用效率的提升;农地经营规模扩大对环境约束下的农户土地利用效率产生正面影响,但现实中普遍存在的小规模化经营和土地细碎化消减了正面影响。土地产权的稳定性能够提升环境约束下的农户土地利用效率,但无论是集体土地产权还是承包经营权以及农户间非正式的土地流转产权关系稳定性较差,不利于环境约束下的农户土地利用效率的提高。  相似文献   
999.
面向地震应急准备的居民地遥感提取及量化分析   总被引:2,自引:1,他引:1  
李金香  李亚芳  李帅  王伟  陈勇 《地理科学》2016,36(11):1743-1750
运用灰度共生矩阵、数学形态学等方法提取新疆新源地区高分一号2 m分辨率影像居民地信息,运用目视解译、影像叠加分析、缓冲区分析等方法,进行居民地量化分级,为地震应急准备提供数据支持。结果表明:研究区在地震烈度为度及以下区域,埋压主要集中在单层结构为主的建筑区;当地震烈度高于度且造成多层建筑大面积倒塌时,县城等人口密集区为首要救援区;在地震应急准备时,应对交通条件三等区和交通条件四等区重点关注,增加应急物资储备点,对山区居民地,应考虑道路毁坏情况,转换救援方式,做好应急预案。  相似文献   
1000.
从致灾因子、孕灾环境、承灾体3个方面分析了洪涝灾害承灾体易损性,阐述了产业结构的发展趋势与动力,分析了产业结构对洪涝灾害承灾体易损性的影响。以安阳市为例,在分析典型年份产业结构的基础上,运用地均产值指标分析了2010年三大产业产值效益以及由产业结构变化导致的土地利用结构变化,探讨了典型年份产业结构调整对承灾体易损性的影响。结果表明:安阳市第一产业产值比重呈现减小趋势,第二产业比重最高且基本稳定,第三产业则呈增长趋势。在典型年份,第二产业产值所占比重最高时,承灾体易损性增强,洪涝灾害造成经济损失严重,且与第一产业所占比重呈相反发展趋势,与第三产业呈现相同发展趋势;洪涝灾害期间日降雨量明显减小,但其造成的损失却有加大趋势。近年来,安阳市第一产业产值比重下降,降低了承灾体的易损性;第二产业比重平稳增长以及第三产业比重上升较快,则增强了承灾体的易损性。  相似文献   
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