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41.
梅州市名城文化景观的保护与开发研究   总被引:5,自引:1,他引:5  
从名城文化内涵出发,着眼于作为客家人文中心和名城文化景观的集中的梅州市区,全面分析了其中丰富多样的文化景观资源的特征及其文化内蕴。揭示了梅州名城文化景观保护与开发过程中的成绩与存在问题。并从文化地理学的视觉,结合旅游开发和城市规划,论证了科学保护与开发梅州名城文化景观的下述对策与途径的必要性与可行性:提升名城办的职能并与相关部门共营名城文化氛围;强化名城轴线与标志性文化景观;抢救与保护“老字号”等一批文化景观景区;适度利用,以积极的开发促其效的保护。  相似文献   
42.
城市景观格局与热岛效应研究进展   总被引:5,自引:0,他引:5  
概述了城市景观格局和城市热岛效应及城市景观格局对城市热岛效应影响等领域的研究现状,探讨了城市景观格局对城市热岛效应的影响作用,并结合城市景观格局研究中的新领域——景观格局优化,提出了解决城市热岛问题的新思路,即通过优化景观格局来达到缓解甚至消除热岛效应。展望了城市景观格局和城市热岛效应研究领域存在的问题和面临的任务。  相似文献   
43.
We present a pattern-based regionalization of the conterminous US – a partitioning of the country into a number of mutually exclusive and exhaustive regions that maximizes the intra-region stationarity of land cover patterns and inter-region disparity between those patterns. The result is a discretization of the land surface into a number of landscape pattern types (LPTs) – spatial units each containing a unique quasi-stationary pattern of land cover classes. To achieve this goal, we use a recently developed method which utilizes machine vision techniques. First, the entire National Land Cover Dataset (NLCD) is partitioned into a grid of square-size blocks of cells, called motifels. The size of a motifel defines the spatial scale of a local landscape. The land cover classes of cells within a motifel form a local landscape pattern which is mathematically represented by a histogram of co-occurrence features. Using the Jensen–Shannon divergence as a dissimilarity function between patterns we group the motifels into several LPTs. The grouping procedure consists of two phases. First, the grid of motifels is partitioned spatially using a region-growing segmentation algorithm. Then, the resulting segments of this grid, each represented by its medoid, are clustered using a hierarchical algorithm with Ward’s linkage. The broad-extent maps of progressively more generalized LPTs resulting from this procedure are shown and discussed. Our delineated LPTs agree well with the perceptual patterns seen in the NLCD map.  相似文献   
44.
1990~2005年间,是广州市经济快速发展和城市景观变化最大的时期,以同时段TM影像解译得到广州市的土地覆被类型图,从数量结构、空间信息及位置转移和景观等方面,分析了广州市土地覆被的动态特征.数量结构的研究结果显示:在快速城市化过程中广州市的耕地、林地等自然资源的利用程度在加大,自1995年起,这种变化的趋势开始减缓;土地覆被类型之间的信息与位置的转移变化频繁,并且表现出空间位置分异的特征.景观特征指数分析结果表明:广州市城市土地覆被向破碎化方向发展,城市建设用地呈扩展之势.  相似文献   
45.
Gong  Jie  Xie  Yuchu  Cao  Erjia  Huang  Qiuyan  Li  Hongying 《地理学报(英文版)》2019,29(7):1193-1210
Journal of Geographical Sciences - Mountains in western China, hosted rich biodiversity and millions of people and inhabitant with vital ecosystem services, had experienced the most serious...  相似文献   
46.
2003-2017年北京市地表热力景观时空分异特征及演变规律   总被引:6,自引:3,他引:6  
利用2003-2017年MODIS地表温度数据,分别从数量、形状和结构角度揭示北京市不同季相和昼夜间地表热力景观时空分异特征,并进一步通过热力等级变化图谱及质心迁移轨迹揭示城市热力景观空间演变规律,探究热力景观等级转换生态过程。结论如下:① 城市地表热力景观季节和昼夜空间特征差异显著;② 中温区在城市热环境中占主导地位。白天中温区是最不稳定的热力景观等级;夜间次低温区和次高温区不稳定性增加;③ 地表热力景观等级变化以稳定型占主,反复变化型和前期变化型次之。地表热力景观等级通常呈现逐级递增或递减规律,山区呈现逐级降温趋势,北部城郊—山地交错地带表现出次低温和中温的反复转向,南部地区有一定的升温趋势;④ 2003-2017年高温区面积增大且质心向城市中心集中,低温区质心向城市外围扩散。生态涵养发展区对北京市地表热力景观质心迁移贡献率最高。热力景观时空分异特征及演变规律可为有效缓解城市热岛效应提供管理决策支持。  相似文献   
47.
湘北红壤坡地雨水过程的水土流失及其影响   总被引:7,自引:0,他引:7  
谢小立  王凯荣 《山地学报》2003,21(4):466-472
模拟主要利用方式构建的垫面为主导因子,采用径流场实测方法,通过4a(1998~2001年)实地观测试验,剖析不同下垫面对雨水地表径流及其过程的影响。研究表明:降雨(时间分布及其强度)是影响地表径流特征的主导因素;年降雨量与地表径流量和系统水土流失量呈正相关。不同垫面地表径流产量有显著性差异;雨水径流过程的土壤和养分流失有相似的表现。在假定雨水年份的基础上,应用不同雨水年份出现概率指标,推算出:湘北红壤坡地现今利用状况下,雨水产地表径流过程的年均水土流失量及其养分(有机质、N、P、K)损失量;和可最大开发利用时,可能带来的水土流失与养分损失。提出"利用坡地集雨利用优势,构建与单元生态系统水循环平衡相适应的坡地农林复合生态系统,通过水平衡生态建设来维系生态系统的水分平衡"观点。  相似文献   
48.
Based on the information from forest resources distribution maps of Luoning County of 1983 and 1999, six indices were used to analyze spatial patterns and dynamics of forest landscapes of the typical region in the middle of the Yihe-Luohe river basin. These indices include patch number, mean patch area, fragment index, patch extension index, etc. The results showed that: (1) There was a rapid increase in the number of patch and total area from 1983 to 1999 in the study area. The fragment degree became very high. (2) The area of all the forest patch types had witnessed great changes. The fractal degree of each forest patch type became big from 1983 to 1999. The mean extension index of Robinia pseudoacacia forest, non-forest, shrub forest, sparse forest, and Quercus species forest increased rapidly, but that of economic forest became zero. The fractal dimension each showed that forest coverage has been promoted. (3) The changes of landscape patterns were different in different geomorphic regions. From 1983 to 1999 the vegetation cover area, the gross number and the density of patch, diversity and evenness of landscape were all reduced greatly in gullies and ravines, but the maximum area and the mean area of patch types were increased. In hilly region, both the forest cover area and the number of patch increased from 1983 to 1999, but the mean area of patch was reduced greatly. In mountain region, even though the area under forest canopy reduced from 1983 to 1999, the patch number was increased greatly, the mean area of all patch types was reduced, the extension index, diversity index and evenness index of landscape were all increased. Furthermore, because of different types of land use, human activity and terrain, the vegetation changes on northern and southern mountain slopes were different. According to these analyses, the main driving forces, such as the policies of management, market economy, influence of human activities etc. are brought out.  相似文献   
49.
ABSTRACT. Most of us have not known—or cared—where our electricity comes from. Our attitude is changing, however, as we turn toward wind energy, now the fastest‐growing renewable energy resource in the world. Because we cannot extract and transport the raw energy of the wind, reaping its many environmental benefits requires that we cope with the landscape presence of its development wherever it occurs. Sometimes this interferes with the value of open space, and sometimes it may be close to subdivisions. It is the immobility and very visibility of wind power that makes its presence unavoidable. In that regard it cannot be hidden underground, stored in tanks, or moved by trains. It is an energy resource that reminds us that our electricity comes from somewhere. The more we wish to tap the power of the wind, the less we will be able to avoid the responsibilities that our demand for energy brings. This necessary bargain, first evident near Palm Springs, California, is now being experienced wherever wind power is being developed.  相似文献   
50.
This article considers the history of a particular Latvian cultural landscape, located on the coast of the Baltic Sea. Known as an aizjomi landscape, it consists of small, humanly made tilths on the seashore. These features are both physical elements and repositories of historical and cultural meaning. In one sense, through hard labor humans created the aizjomi landscape, adjusting the morphological and dynamic elements of the landscape and continually maintaining them. These human efforts made agriculture possible in the dunes, and in so doing they fashioned a means for producing a livelihood and, indeed, for sustaining life. The aizjomi landscape became a materialization of the people's day‐to‐day life in the middle and late nineteenth century and can thus be considered a “taskscape,” pulsating simultaneously with the rhythm of nature and historical events. I have analyzed empirical evidence from archival documents, reviewed ecological and historical studies, and conducted field research on specific farming practices that shaped the landscape that, in turn, shaped agricultural activities. Through a retrospective analysis I trace the development and decline of the aizjomi landscape.  相似文献   
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