首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
2.
3.
4.
5.
小城镇空间结构变迁的形式和动力   总被引:7,自引:3,他引:7  
小城镇向心增长的空间过程主要表现为郊区城镇化、内城更新改造、反向扩展3种形式,是小城镇对农村人流、物流的集聚和内部空间结构的优化。小城镇离心增长的空间过程主要表现为城镇郊区化、产业区位变迁、外向扩展3种形式,是小城镇生产力发展到一定阶段后城镇要素向近郊区的扩散。小城镇向心增长和离心增长是集聚与扩散相互作用的表现,社会经济发展是小城镇空间变迁的根本动力,功能-形态互适机制是其演变的主要机制。  相似文献   

6.
This paper describes the characteristics of accessory apartments (rented housing units within owner-occupied single family homes) and the circumstances which give rise to them. Survey data from a New York suburb indicate that these apartments provide inexpensive housing for entry level workers, many of whom are related to the home owners. Analyses suggest that “empty nest’ households who anticipate a decline in income and live in a house whose structure facilitates a conversion are likely to create accessory apartments in their homes. Some implications of these findings for residential succession in suburban areas are explored.  相似文献   

7.
干旱区水土资源时空变化的定量研究   总被引:11,自引:9,他引:11  
水资源是制约干旱区土地资源开发利用的主要自然因素,水、土资源利用在时间和空间上平衡与否的矛盾影响着干旱区生态环境与社会发展。用定量化的数学模型表示二者的互相影响,能描述、解释和预测二者关系并能为制定对策提供依据。本文首先分析了干旱区土地利用与水资源的相互影响,然后对水土资源相互影响下时空变化的模拟方法和理论进行了综述。一方面从蒸散的计算、模拟地下水补给、模拟区域尺度上土地利用影响、模拟土地管理措施影响、模拟抽取地下水影响、以系统方法模拟土地利用影响等几方面对土地利用影响下水资源的时空变化模拟进行了综述。同时对水资源影响下土地利用变化的模拟从主要考虑水文作用的水文-植被模型的建立应用及引入人为因素为驱动力的土地利用变化模拟两方面做了综述。文章最后进一步概括了干旱区水土资源时空变化模拟的趋势并就此方面的研究提出了三点展望意见。  相似文献   

8.
《Urban geography》2013,34(7):641-655
In the past few years, a vastly enriched information source on housing vacancies has become available through real estate industry-sponsored sites on the Internet. This rich information source has the potential to influence spatial patterns and processes in the search for housing by eliminating information barriers in the search process. Thirty years ago, geographers documented the constraints to the search process caused by limited or biased information fields. The question addressed by this research was whether this new information availability would change the search patterns documented in the 1970s. In order to investigate this question recent movers in Wake County, North Carolina, were surveyed in early 2000, and the characteristics of Web users were compared with nonusers. The major finding of this research is that to date, the Internet has had little impact on search patterns, except that those using the Internet tend to visit a larger number of houses personally than those who do not use the World Wide Web as an information source. [Key words: residential mobility, housing search, Internet.]  相似文献   

9.
This work examines the use of an annually updated metropolitan data system as a tool for evaluating benign racial location policies during the first year of the Section 8 Existing Rent Supplement program. Case-study evidence shows that the rent supplement program (with benign locational policies) is ineffective in reducing the isolation faced by minority groups, and that the information used to monitor compliance of the program with benign locational policies lags badly behind the true state of affairs. As a result, new areas of racial concentration have been encouraged and augmented.  相似文献   

10.
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   

11.
12.
FLOODPLAIN DELINEATION AND HOUSING SUBMARKETS: TWO CASE STUDIES   总被引:1,自引:0,他引:1  
The effect of floodplain designation on the residential real estate market in two communities, Elmira, NY and Wilkes-Barre, PA, is presented. Discriminant analysis differentiates between floodplain and nonfloodplain housing, using as independent variables characteristics of the houses sold. Several varibles define submarkets, but they vary between the communities. Only selling price and lot size were significant for both communities. Distinct floodplain and nonfloodplain housing markets can be differentiated. This allows for isolation of socioeconomic and environmental variables that may contribute to the recovery of housing values following flooding or to the implementation of land use controls associated with floodplain designation.  相似文献   

13.
基于GIS的新疆棉花生产发展时空变异分析   总被引:11,自引:1,他引:11  
在新疆棉花生产统计数据库建立的基础上 ,利用地理信息系统工具软件ArcView制作新疆历年棉花播种面积、单产和总产分布图 ,并以 1 980、1 985、1 990和 1 995年为例对新疆棉花生产的时间和空间分布进行分析 ,同时还分析了 1 997年棉花播种面积占耕地面积和总作物播种面积的比率分布。进入 90年代后新疆棉花生产发展迅速 ,播种面积、单产和总产都有大幅度增加 ,1 995年总产达到 30× 1 0 5t以上的县有莎车、阿克苏、沙雅、阿瓦提、麦盖提、巴楚 6县 ,主产区主要分布在南疆的库尔勒 -阿克苏 -莎车和北疆的昌吉 -博乐沿线各县 ,1 997年已有 1 4个县棉田面积占耕地面积的比率大于 5 0 %。新疆棉花生产已达到一定的规模 ,宜在稳定中求发展 ,注意防止规划和管理不善可能造成的土地退化 ,以保障农业生产持续发展。  相似文献   

14.
15.
The recent development of intermodal transportation and the relaxation of U.S. transport regulations have encouraged ocean carriers to rationalize their port schedules. Container shipping is therefore believed to concentrate shipping at a few large ports. Port traffic analysis, using the Lorenz Curve and Gini Coefficient, reveals, nevertheless, that the structure of the U.S. port system is actually becoming less concentrated. The challenge of secondary ports and changes in the transportation system explain this deconcentration.  相似文献   

16.
Life is an evolution. We concentrate a period of this evolution in a stable view which we call a form, and, when the change has become considerable enough to overcome the fortunate inertia of our perception, we say that the body has changed its form. But in reality the body is changing form at every moment; or rather there is no form, since form is immobile and reality is movement. What is real is the continual change of form: form is only a snapshot view of transition.  相似文献   

17.
18.
《Urban geography》2013,34(1):27-47
Prices for standard lots and acreage were collected for 1975 and 1980 in 30 metropolitan areas and then analyzed, using multiple regression, to identify factors which would explain variations among metropolitan areas. Extreme price variations were observed. For example, from 1975 to 1980, the price of a standard residential lot increased as little as 31% in one area, while the price rose 1 76% in another. Over 80% of the variation in lot price increases was explainable by a model combining land supply and demand factors. In their order of importance, the factors were: (1) an index of regulatory restriction, (2) population increases, (3) per-capita income increases, and (4) job increases. The analysis suggests that public regulatory, infrastructure and tax policies can significantly affect land supply and demand and, in turn, prices. Communities that choose to manage growth must monitor land supply and demand and adjust their policies to ensure competitive noninflationary land markets. Otherwise major increases in land prices for housing and businesses may result.  相似文献   

19.
20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号