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51.
区域土地利用及土地覆盖的空间格局研究--以广西梧州市为例 总被引：18，自引：1，他引：17
从分析梧州市土地利用现状入手, 总结其土地利用的现状特征, 而后在引入多样性指数、优势度指数、均匀度指数和破碎度指数的基础上, 对梧州市土地利用／ 覆盖的空间格局进行了定量分析。最后, 根据计算结果得出有关结论。 相似文献
52.
As an important component of China' transportation systems, for a long time, the insufficient performance of transport in Qinghai- Tibet Plateau (QTP) was a bottleneck restricting the economic growth and social development in this area. Nevertheless, the implementation of the western development strategy has accelerated the preliminary construction of comprehensive transport network since 2000. Due to the large area and significant geographical heterogeneity, there is a growing need to understand the relationship between transportation and economic development based on the perspective of spatial difference. By using GIS-based raster analysis and Geographically Weighted Regression (GWR) model, we investigated the spatial-temporal distribution of highway, railway and airport accessibility, respectively, and estimated the correlation and heterogeneity between transport accessibility and the level of economic development. Results revealed that: (1) Transport accessibility in the QTP improved by 53.38% in the past 15 years, which is specifically embodied in the improvement of both highway and railway. (2) Accessibility presented prominent differentiation in the space, increasing from west to east and reducing with the rise of elevation, specifically, the best accessibility area of the highway is below 4000m above sea level, while the area with an altitude of over 4000 m has the lowest aviation time cost. (3) In general, the long weighted average time cost to critical transport facilities posed significantly negative effect on county economic growth in QTP, more positively, the adverse effect gradually weakened over time. (4) Obvious heterogeneity exists at the influence of different transport accessibility factors on the level of economic development, reflecting both in the horizontal space and altitudinal belt. Therefore, region-specific policies should be addressed for the sustainable development of transport facilities as well as economy in the west mountain areas. 相似文献
53.
城市景观为城市文化的载体,是城市物质表现,而城市文化同时又建设和改变着城市景观。佛山市是国家历史文化名城,景观与文化的相互作用显著,文中试以佛山市为例,追溯城市的文化背景、景观的空间演变,从历史文化景观、工商业专业文化景观、宗教文化景观、民俗文化景观、园林绿化景观等五个方面进行了文化特征分析,指出构建历史文化名城和现代生态城市相结合的综合性城市是佛山市今后作为区域中心城市的景观建设的取向。 相似文献
54.
经济地理学新的思维范畴 总被引：8，自引：0，他引：8
全球经济一体化与信息时代的到来,给经济地理学带来了新的变化,加之实践的检验,经济地理学由过去那些“区位论”,“生产布局”相应地发展到空间理论和信息理论,重在分析机制因素,时空的变化也更加深刻了,本学科比较综合,具有广阔的区域空间,复杂的内涵 ,其学科的创新在于在时空耦合度上使经济和社会同人口,资源,生态环境之间保持和谐,高效优化有序的发展,逐步建立具有我国特色的资源节约型的社会经济消费体系。着重分析了经济地理学新的思维范畴与研究趋势,强调用科学方法来检验以前的结论,用统计方法（层面分析）来解释数量关系,用GIS的分析法来印证空间布局的合理性。 相似文献
55.
WANG Mei-quan GUAN Qing-wei HUANG Zong-sheng ZHAO Jia-hao LIU Zheng-ji ZHAN GHao BAO Xun-wen-qian WANG Lei YE Yu-qian 《山地科学学报》2022,31(9):2587-2600
Rock fissures constitute the main habitat type in the karst rocky desertification (KRD) area, but the effects of their network morphology on soil properties remain unknown. To address this, we investigated 46 rock vertical profile plots in Guizhou Province of China and classified their habitats using the morphological characteristics of their fissure networks. The response characteristics of soil nutrients and enzyme activities to the rock fissure morphologies in different rock habitats were discussed, and the main factors affecting soil nutrients and enzyme activities were comprehensively analyzed. Rock fissure networks were divided into three types: Type 1, a random type, with a low dip angle, long trace length, multiple turns, multiple connections, and high density; Type 2, a uniform type, with a moderate dip angle, moderate trace length, fewer turns, fewer connections, and moderate density; and Type 3, an aggregation type, with a high dip angle, short trace length, fewer turns, moderate connections, and low density. Soil nutrient levels and enzyme activities were the highest in Type 1, followed by Types 2 and 3. There were no significant differences between the total phosphorus and available phosphorus content in Types 1-3. The dip angle, fractal dimension, and average trace length were identified as the main factors affecting soil nutrients and enzyme activities, and Type 1 was the most conducive for soil nutrient and enzyme accumulation. The restoration of Type 2 and 3 areas should be emphasized in future research, as these results will help guide vegetation restoration in KRD areas. 相似文献
56.
The complex landforms of a Shan-shui City (Shan-shui refers to mountains and rivers) significantly impact the selection of locations for logistics enterprises. This paper takes Chongqing, one of the most typical Shan-shui Cities in China, as the research object, and adopts spatial analysis methods and a mediating effect model, to explore the role of mountains and rivers in the formation of logistics enterprises' spatial pattern on the street scale. The study results reveal that 90% of the logistics enterprises in the central urban areas of Chongqing are located in the low-altitude area below 353m above sea level, and distributed in a north-south direction along the mountains, as a result of blockage by mountain ranges, such as those of Zhongliang Mountain and Tongluo Mountain. More than 70% of the logistics enterprises are located less than 5 km from either the Yangtze River or Jialing River, spreading along the rivers. In addition, more than half of the logistics enterprises in commercial and financial, and residential land are located within the urban core area, while 80.83% of the logistics enterprises located in warehousing land and industrial land are concentrated in the urban expansion area. In areas with high land prices, the negative effect of altitude on logistics enterprise agglomeration is weakened, while the promotion effect of river proximity on logistics enterprise agglomeration is enhanced. In the urban core area with the advantage of low altitude and proximity to the Jialing and Yangtze Rivers, the role of mountains and rivers on logistics enterprises is not apparent; in contrast, in the urban expansion area with more complex landforms, land price can be an effective means for the government to macro-manage the spatial pattern of logistics enterprises in a Shan-shui City. 相似文献
57.
基于QTM的海平面上升分析与模拟 总被引：1，自引：0，他引：1
针对海平面上升影响范围分析与模拟这一国际前沿问题,通过研究基于球面四元三角网(QTM)的关键技术问题,包括复杂拓扑关系计算、LOD剖分、球面水淹分析、基于QTM的多分辨率的DEM数据组织方法和分析精度的相关性评定等,以.Net和Direct3D为开发工具,设计开发了基于QTM的海平面上升影响范围评估模型。该研究结果可为全球海平面上升影响的防灾减灾决策提供有效支撑,并推动了球面数据模型和球面格网拓扑分析的理论成果在全球变化预测相关领域的应用进展。 相似文献
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60.
针对使用传统的编程方式进行空间回归分析过于繁杂的问题,本文提出将Python函数式编程引入空间回归分析方法,分析和探讨脚本语言＋函数式编程方式在GIS数据分析中的推广应用前景。编程实践证明,采用Python函数式编程,结合既有的开源软件包,可以有效提高编程效率,减少代码量,将实践人员的注意力集中在问题本身。 相似文献