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1.
针对河南省高速公路建设对城市通达性影响问题,该文通过定义时间阈值,设计了基于人口加权时间距离倒数的通达性指数,在4个时间断面上,研究河南省高速交通网络中通达性时空特征及演化规律,时间距离倒数有效减小了多路径时间距离对分析结果的数字影响。结果表明,随着河南高速交通网络的拓展,城市通达性水平得到了显著的提升,空间收敛显著,边缘城市的提升始终高于中心区域城市;高速公路通车里程增长率与通达性水平的改善存在非协调现象;城市通达性的空间聚集现象震荡走弱,聚集区域减少;城市通达性空间分布变化规律和城市化人口变化规律逐渐趋于协调。  相似文献   

2.
探索性空间分析从统计和图形图表的角度帮助人们更好地认识与理解数据,挖掘出数据的价值。以云浮市郁南县域内农林产业的分布及面积数据为例,基于GIS平台,利用ArcGIS中的探索性空间分析工具对农林业面积的空间特征进行了分析。研究结果表明:县域内东南部分布的农林业点数较密集,而西北部分布的农林业斑块面积较大,农林业点在道路、水源及城镇附近分布密集;距离道路、城镇和水源的远近从不同方面对农林业面积在空间上的分布产生了影响;荔枝和龙眼的面积在空间上显示出正关联性;但农林产业的斑块面积在空间上不具有相关性。  相似文献   

3.
基于RS和GIS的巢湖流域城镇体系空间结构分析   总被引:1,自引:0,他引:1  
在RS和GIS技术支持下,利用相关影像,采用监督分类和人机交瓦相结合的方法对研究区城镇信息进行提取,在此基础上从城镇体系的空间分布特点及空间集聚与扩散效应的角度,对研究区域的空间结构进行分析.研究表明,该城镇体系的空间集聚能力强于扩散能力.  相似文献   

4.
为了解决早期消防站布局不合理带来的问题及提高火灾救援效率,本文选取徐州市区为研究区域,对消防站、可能火灾点、交通网络等进行可视化表达,利用点密度和回转半径分析可能火灾点的空间分布特征;最近距离模型辅以C#代码选择最优路径,并利用网络分析和泰森多边形对消防资源分配进行多角度的空间可达性分析.结果表明:1)可能火灾点的分布总体上呈现出由中心向郊区减少的趋势,集中分布于市中心8 km半径范围以内;2)单个消防站服务的可能火灾点,数量为19—194个不等,距离为40—8735 m不等,30 km/h车速下仅能覆盖33.95%的范围.未来消防站的规划要注重城市化扩张地区的消防要素分配,不可只注重市中心,而忽略市区边缘.  相似文献   

5.
基于多时相TM影像和GIS空间技术,计算了徐州城市空间形态的分形维数和紧凑度指数,运用象限方位分析和缓冲区分析方法,对研究区城镇建设用地的空间分异特征进行定量分析。结果表明,1983~2013年,徐州城镇建设用地扩展了1.4倍;全市范围内,中心点西南区为建设用地扩展的核心区,而中心城区整体向东南方向移动;城镇扩展强度呈现中心向外围"圈层式"扩展趋势。  相似文献   

6.
为了对宁夏城乡关系进行定量评价及空间分异研究,该文基于2013年宁夏19个县区城乡发展数据,构建评价指标体系,采用关联度模型、协调度模型、统筹发展度模型和ESDA-GIS空间分析方法对宁夏城乡关系发展水平和空间格局进行研究。结果表明:宁夏城乡关联度、协调度和统筹发展度整体水平较低,城乡发展呈现"北高南低"的空间分布格局,空间分异明显,空间集聚特征显著,与经济社会发展呈明显的相关性;南部山区是城乡发展的"塌陷区",北部地区是宁夏城乡发展的"核心区";原州区空间极化效应显著,县域尺度的城乡关系空间格局研究较为合理地反映了宁夏的实际状况。  相似文献   

7.
针对当前县域尺度城镇化研究不足,以及传统数理统计模型无法描述城镇化空间集聚特征的薄弱点,从空间自相关视角来探讨县域尺度城镇化空间集聚特征。基于人口、经济、空间及社会4个维度构建县域城镇化体系,运用投影寻踪模型测度县域尺度城镇化,较科学地评价县域城镇化水平;采用空间自相关模型分析县域城镇化空间集聚,并解释其影响因素,实现了对县域城镇化空间集聚规律有效揭示。研究结果表明:安徽县域城镇化水平呈上升态势,存在"南高北低"区域分异;县域城镇化具有显著全局空间集聚,局部H-H区集聚"合-芜-马",L-L区集聚皖北地区;地理区位条件、交通网络改善、中心城市作用及发展政策倾向是影响安徽县域城镇化空间集聚主要因素。  相似文献   

8.
区域尺度海河流域水土流失风险评估   总被引:10,自引:1,他引:9  
李晓松  吴炳方  王浩  张瑾 《遥感学报》2011,15(2):372-387
借鉴USLE的因子选择及综合方法,在遥感和GIS的支撑下对海河流域的水土流失风险进行评估,并对其空间分布特征进行分析.结果表明:海河流域山区水土流失风险显著高于平原地区,北三河山区水土流失风险最低,太行山区最高,永定河上游介于两者之间;水土流失风险"很低"等级主要分布在小于5°的平坦地区,"中"、"高"水土流失风险面积...  相似文献   

9.
湖北省非物质文化遗产丰富,本文利用GIS的空间分析技术,运用核密度分析,最邻近距离分析等方法,对于湖北省内的100种国家级非物质文化遗产的空间分布特征及影响因素进行了分析,得出以下结论:(1)湖北省内国家级非物质文化遗产的分布呈"一核三副"的分布形式,主要分布核心集中在武汉周边。(2)传统戏曲、传统音乐和民间文学的所占比例最高,传统体育、游艺与杂技和传统医药所占比例最小。(3)不同类型的非物质文化遗产在分布上也有所不同。(4)非物质文化遗产整体沿着河流分布,在平原地区分布相对比较集中,在山区则分布不均,类型特征明显。  相似文献   

10.
贾煜  汪泓  蔡宏  张磊 《测绘通报》2022,(2):121-127
西南喀斯特山区地形起伏较大,地物分布较为破碎,致使传统的光谱特征一次分类方法的精度较低。本文基于高分辨率无人机正射影像和地形指标,充分利用无人机遥感影像空间特征、光谱特征、纹理特征及地形特征,采取面向对象CART决策树算法与分层策略提取了研究区土地覆盖类型。研究表明,结合空间地形因子和分层策略的方法减少了破碎区地物间的相干扰,故具有较高的分类精度,总体分类精度达91.2%,Kappa系数为0.87,较传统一次分类精度提高了9.8%,Kappa系数提高了0.13。该方法对西南喀斯特地区土地覆盖解译精度较好,可为土地利用监测提供参考。  相似文献   

11.
莫新宇  祝善友  张磊 《地理空间信息》2013,11(1):61-63,81,13
选取苏州作为研究区,分别利用1986年和2004年2个时相的Landsat5 TM影像数据对研究区土地利用/覆盖类型进行分类,并采用热红外波段进行地表温度反演,在此基础上分析了下垫面类型与热岛效应的时空变化,深入研究了下垫面类型改变对热岛效应的影响。结果表明,近20a苏州市城区大范围扩张,土地利用变化剧烈,整体表现为水体、植被向不透水下垫面的高强度转化;城市热岛范围由老城区向四周成倍扩大,热岛强度由3.12°增至4.76°,热岛效应变化与土地利用时空变化之间具有明显的对应关系。  相似文献   

12.
蔡栋  李满春  陈振杰  魏巍  胡伟 《测绘科学》2010,35(3):106-109
城市边缘区是城乡共同作用的地域单元。如何及时、准确地划分城市边缘区,是目前研究在GIS和RS相关软件的支持下,以南京地区2003年的Landsat TM遥感影像为计算依据,以信息熵理论为基础,结合分析城市边缘区土地利用特征,改进了传统的土地利用信息熵模型,分析熵值分布特点,最后采用突变检测的方法,以熵值60和68确定南京城市边缘区内、外边界的位置,划定了南京城市边缘区的大致范围。研究认为城市边缘区边界是动态变化的;在城乡断面上城市边缘区的景观紊乱度明显高于城市核心区和城市影像区,这为客观划分城市边缘区和利用遥感影像监测城市边缘区的动态变化提供了一个新的途径。  相似文献   

13.
In the present study, the Cartosat-I digital elevation model (DEM) was utilized to deduce the vertical characteristics of Ranchi urban area and its relation to long term built-up expansion (1927–2010). The DEM represents moderate variation in terrain relief ranging from 595 m to 754 m with majority of area exhibiting upto 3° of slope and 3° to 6° indicating flat to undulating nature of terrain in Ranchi township. The DEM was used to generate location of sinks within urban area, which are generally delineated along the drainage channels, adjacent to high-rise built-up land and along the elevated road network. The pattern of urban sprawl over the eight decades (1927–2010) were examined with reference to terrain relief zones, which indicated that the built-up growth was mainly taken place over the elevation range of moderate (620–660 m) (67.0%) and high relief (660–680 m) (19.8%) zones. Although earlier preference for built-up development was more in high elevation zones (660–680 m), the low elevation zones (<600–620 m) are now preferred for multistoried built-up land development where better groundwater availability occur. The spatial pattern of vertical growth of built-up land was assessed using contour density obtained from Cartosat-I DEM. The results show that the high density contours predominately correspond to hilly area and high-rise buildings at majority of locations. The urban sprawl pattern and population trend exhibited rapid increase in vertical built-up growth after 1996 indicating beginning of urban densification in Ranchi township.  相似文献   

14.
This study presents a remote sensing and geographic information systems-based approach for using US EPA’s Storm Water Management Model (SWMM) in urban environment. Cartosat-1 PAN + IRS-P6 LISS-IV merged product was used to map land cover in part of Surat city at 1:10,000 scale. Cartosat-1 stereo pair was used for deriving digital elevation model of the study area. Geo-informatics-based methods were developed for delineation of sub-catchment areas, assignment of sub-catchment outlets and estimation of characteristic width. It was observed that 59% of the developed area in the study region was directly or indirectly connected to the storm water drainage network. Furthermore, dynamic rainfall-runoff simulation on three-day rainfall indicated that the average runoff coefficient on the urbanized sub-catchment areas which were directly connected to the drainage network was 0.92 as against 0.88 on those urbanized sub-catchments without having direct access to storm water drainage.  相似文献   

15.
基于MODIS数据的长株潭地区城市热岛时空分析   总被引:7,自引:1,他引:6  
历华  曾永年  贠培东  黄健柏  邹杰 《测绘科学》2007,32(5):108-110,116
基于MODIS影像,采用分裂窗算法反演的地表温度对长株潭地区城市热岛空间分布与季相变化特征、影响因子进行定量研究。结果表明,长株潭地区春季和夏季存在明显的城市热岛效应,而冬季和秋季城市热岛并不明显;地表覆盖类型对城市热岛的影响十分明显,长株潭地区春、夏、秋季植被绿地状况与城市热岛呈现明显负相关分布,其中以夏季最为明显,夏季地表温度与NDVI相关系数的平方R2达到0.8193,即植被覆盖对城市地表温度的影响显著。因此,城市植被的分布与季节变化影响着城市热岛的强度与时空分布,揭示出植被绿地对降低城市热岛效应具有重要的作用,大范围的绿地建设能有效降低城市热岛效应。  相似文献   

16.
Urban land density is an important factor to understand how cities expand. An “Inverse S-shape Rule” was implemented for the first time to analyze urban land density in Northeastern Thailand using the four cities Khon Kaen, Udon Thani, Nakhon Phanom, and Nong Khai as study sites. Land density function was tested using different data classification techniques from previous studies. Each city was investigated over two different time periods between 2002 and 2015. Declining pattern characteristics of metropolitan area density outward from city centers can be quantified by fitting the parameters to urban land density functions. An inverse S-shape function was identified as the best data fit. The four selected cities showed conventional density variation for decline in urban land area from city centers to outlying areas. Overall trend indicated that cities became more compact over time since the density differences between the urban core and urban fringe were greater with increasing infilling growth within the urban boundary. All four cities increased in size over time; however, the increasing amount of built-up land in the surrounding rural areas did not follow the same trend in each case. Some functional parameters required careful interpretation because of the linear shape of the city as in the case of Nakhon Phanom. Using highly detailed urban data resulted in lower densities of urban areas compared to the conventional pixel-based classification, and this affected the overall shape of the inverse S-shape function. The fitted parameters and their changing trends indicated that the urban land density function was useful for understanding urban form and urban sprawl in Thailand. Results can be used to develop a specific framework for other cities with similar attributes in the future.  相似文献   

17.
This paper is based on the study done in Rohini and surrounding project area of Delhi. The objective of the paper is to evaluate the application of aerial remote sensing for preparing inventory of derelict land around urban areas. Inventory and monitoring of derelict lands is very important for urban planners and decision makers. Because of unmanageable growth of urban areas, the pressure on rich agricultural land in the urban-rural fringe is increasing day by day, while vast stretches of derelict land are lying unused. These derelict lands can be used for urban development, if properly mapped. An operational remote sensing methodology has been worked out. A classification has been developed and used for this study. Results of the ground truth collected have proved the efficacy of aerial remote sensing for such studies.  相似文献   

18.
The urban forest plays an important role in mitigating the urban heat island. However, the cooling effects of different types of urban forest are unclear. In addition, the fairness of the cooling effect of the urban forest has not been discussed. In this study, the land surface temperature (LST) of Changchun City, China was obtained from Landsat ETM+ data and then correlated with detailed urban forest information derived from the high-spatial-resolution Google Maps in order to determine the cooling intensity and cooling distance of different types of urban forest. In addition, the Gini coefficient was used to evaluate the equity of cooling services provided by the urban forest. The results indicated that (1) the total area of urban forest in Changchun City is 106.69 km2 and is composed of attached forest (AF, 45.83 km2), road forest (RF, 23.87 km2), ecological public welfare forest (EF, 23.24 km2) and landscape forest (LF, 13.75 km2); (2) the cooling effect of different types of urban forest varies. The cooling intensity and cooling distance are 3.2 °C and 125 m (LF), 0.2 °C and 150 m (EF) and 0.6 °C and 5 m (AF), and RF had no cooling effect; and (3) the cooling effect of urban forest benefits approximately 760,000 people in Changchun City, and the Gini coefficient of the cooling services of urban forest was 0.29, indicating that the cooling service was reasonable. Therefore, we demonstrated that ETM+ and Google data are a convenient and affordable approach to study the LST on an urban scale, and the Gini coefficient could be a meaningful indicator to evaluate urban ecological services.  相似文献   

19.
In this study, we presented a mono-window (MW) algorithm for land surface temperature retrieval from Landsat 8 TIRS. MW needs spectral radiance and emissivity of thermal infrared bands as input for deriving LST. The spectral radiance was estimated using band 10, and the surface emissivity value was derived with the help of NDVI and vegetation proportion parameters for which OLI bands 5 and 4 were used. The results in comparison with MODIS (MOD11A1) products indicated that the proposed algorithm is capable of retrieving accurate LST values, with a correlation coefficient of 0.850. The industrial area, public facilities and military area show higher surface temperature (more than 37 °C) in comparison with adjoining areas, while the green spaces in urban areas (34 °C) and forests (29 °C) were the cooler part of the city. These successful results obtained in the study could be used as an efficient method for the environmental impact assessment.  相似文献   

20.
Land surface temperature (LST) of Beijing area was retrieved from Landsat TM thermal band data utilizing a radiative transfer equation and the urban heat island (HUI) effects of Beijing and its relationship with land cover and normalized difference vegetation index (NDVI) were discussed. The result of LST showed that the urban LST was evidently higher than the suburban one. The average urban LST was found to 4. 5°C and 9°C higher than the suburban and outer suburban temperature, respectively, which demonstrated the prominent UHI effects in Beijing. Prominent negative correlation between LST and NDVI was found in the urban area, which suggested the low percent vegetation cover in the urban area was the main cause of the urban heat island.  相似文献   

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