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1.
The structure and dynamics of geosystems in the northwestern part of Western Siberia is considered using the Kazym-Lyamin interfluve, based on the landscape-assessment map for the middle part of the Khanty-Mansi Autonomous District. The study used the landscape structural-dynamical approach and the methods of studying the spatio-temporal dynamics of taiga geosystems.  相似文献   

2.
1:25万《毛乌素风沙地貌图》的编制   总被引:2,自引:1,他引:1  
风沙地貌图是认识和研究沙漠(沙地)最基本的图件。毛乌素沙漠沙丘类型复杂多样,对毛乌素沙漠风沙地貌进行详细划分,编制《毛乌素风沙地貌图》对深入研究毛乌素沙漠风沙地貌成因、分布和演化规律具有重要意义。根据编图范围和印刷纸张的要求,将《毛乌素风沙地貌图》的比例尺确定为1∶25万。选用1∶10万地形图作为基础资料,并以1∶5万地形图和1∶20万地质图作为补充资料;专题内容资料以landset-8卫星影像为主,结合Google Earth影像对部分细节内容进行补充。在形态成因相关分析的基础上建立地貌分类体系,将毛乌素沙漠地貌划分为风成地貌、湖成地貌、流水地貌、干燥地貌、黄土地貌和其他等6类,其中风成地貌是本图重点展示的内容。根据毛乌素沙漠的地貌特征,采用图例系统和地貌晕渲相结合的方法表示毛乌素沙漠的具体地貌类型,其中图例系统包括底色、符号、代码和注记等多种表示方法,地貌晕渲的使用增强了地貌的立体感,使地图看起来更加美观。  相似文献   

3.
关于沙漠化地图编制的原则与方法   总被引:13,自引:3,他引:10  
沙漠化是当前一个世界性的重要环境问题,其结果造成生物生产量的下降,土地生产潜力的衰退和可利用土地资源的丧失。它影响到全球陆地面积的1/3和占世界14%的人口,而且每年还以5-7万平方公里面积的速度在蔓延,因此沙漠化的防治便成为全球所关心的一个生态问题和环境保护问题。  相似文献   

4.
腾格里沙漠虽经过多次小规模专题考察,始终未见有沙漠专题地图编制出版,多数只作为专著中的插图加以表现。为此,编制《腾格里沙漠地貌图》显得十分重要,不仅能反映出腾格里沙漠的全貌,还能体现沙漠发展规律、演变特点、分布特征等。依据腾格里沙漠的图幅范围、地貌类型以及印刷纸张规格的要求,将《腾格里沙漠地貌图》的比例尺定为1∶40万。选用1∶25万地形图作为地理基础底图,采用1∶10万地形图作为沙丘符号编绘过渡性的工作底图,专题内容编绘以Google Earth影像资料为主。《腾格里沙漠地貌图》的地貌类型包括风积地貌、风蚀地貌以及其他地貌,其中风积地貌是重点展示的内容。根据腾格里沙漠地貌类型,在编图过程中共设计了16种形态结构类型符号,采用分层设色表示沙丘相对高度,用箭头符号表示沙丘移动方向。  相似文献   

5.
COVID-19疫情对于休闲业造成重大影响。论文基于移动定位数据,利用核密度空间分析法、非参数检验方法,定量解析COVID-19疫情对北京市三环路以内休闲区域在清明节和劳动节人口热力影响。研究指出: ① COVID-19疫情对于北京市节日休闲区域人群热力影响显著,研究选取的3类休闲区域人群热力在2020年清明节、“五一”劳动节分别较2019年同期下降54.2%、53.0%。其中:风景名胜、购物服务、酒店住宿人群热力在清明节分别下降53.6%、57.5%、52.9%,在劳动节分别下降48.5%、52.0%、55.6%。② 风景名胜细分行业中不同类型区域人群热力受影响程度存在差异。3类细分行业区域清明节、劳动节降幅大体呈:寺庙教堂(41.7%、50.3%)<公园广场(53.1%、47.1%)<景区景点(61.1%、51.2%)。Wilcoxon秩和检验表明,寺庙教堂人群热力逐小时变化波动更小,总体呈现出观光游览<日常休闲<宗教信仰的行为需求差异。③ 北京市三环路以内休闲区域人群热力受COVID-19疫情影响程度与未受突发事件影响时休闲区域人群热力、休闲区域面积分别呈显著负、正相关性,其原因可归结为休闲人群风险感知与疫情防控的空间环境因素。研究可为评估COVID-19疫情对于中国大城市休闲业态影响提供科学依据。  相似文献   

6.
基于微博语义分析的重庆主城区风貌感知评价   总被引:1,自引:1,他引:0  
采用社交网络数据对城市进行感知与评价是一种新的城市感知定量研究方法。本文将新浪微博签到数据作为城市感知的数据来源,通过文本挖掘和语义分析方法,探索用户对重庆主城区城市风貌的感知与评价。针对重庆主城区特色风貌片区,研究形成了签到地图、情绪地图和对象地图。签到地图客观反映重庆主城区新浪微博用户活跃程度的空间分布特征;情绪地图挖掘活跃用户对空间的情绪表达和正负面态度;对象地图解析出现这种签到热力分布和情绪分布的原因,发现引发正负面态度的情绪对象。通过分析用户对规划师所设定的风貌要素载体的典型意见,将要素载体归纳为有感知积极、有感知消极、无感知和有感知未设定4类。今后应进一步从要素识别和价值判断两个方面为规划师塑造和管控城市风貌提供参考意见。  相似文献   

7.
Geologic maps are a fundamental data source used to define mineral-resource potential tracts for the first step of a mineral resource assessment. Further, it is generally believed that the scale of the geologic map is a critical consideration. Previously published research has demonstrated that the U.S. Geological Survey porphyry tracts identified for the United States, which are based on 1:500,000-scale geology and larger scale data and published at 1:1,000,000 scale, can be approximated using a more generalized 1:2,500,000-scale geologic map. Comparison of the USGS porphyry tracts for the United States with weights-of-evidence models made using a 1:10,000,000-scale geologic map, which was made for petroleum applications, and a 1:35,000,000-scale geologic map, which was created as context for the distribution of porphyry deposits, demonstrates that, again, the USGS US porphyry tracts identified are similar to tracts defined on features from these small scale maps. In fact, the results using the 1:35,000,000-scale map show a slightly higher correlation with the USGS US tract definition, probably because the conceptual context for this small-scale map is more appropriate for porphyry tract definition than either of the other maps. This finding demonstrates that geologic maps are conceptual maps. The map information shown in each map is selected and generalized for the map to display the concepts deemed important for the map maker’s purpose. Some geologic maps of small scale prove to be useful for regional mineral-resource tract definition, despite the decrease in spatial accuracy with decreasing scale. The utility of a particular geologic map for a particular application is critically dependent on the alignment of the intention of the map maker with the application.  相似文献   

8.
《The Journal of geography》2012,111(5):250-256
Abstract

In this study, pairs of students in fifth and seventh grade generated and answered questions based on maps. More than 90 percent of the questions they generated made sense with reference to the map on which they were based. Each of these questions was coded in terms of both its informational content (symbols, latitude and longitude, and scale) and the process by which a map user obtains the information from the map (map reading, map interpreting, map inferring). Results indicated that students most often generated three types of questions, which together accounted for more than 80 percent of all the questions: 1) read symbol, 2) infer latitude and longitude, and 3) interpret scale. Qualitatively, the questions were analyzed for what they revealed about student confusion about map content. Problems with all three aspects of map content were common among both fifth- and seventh-grade students. The problem-posing technique proved useful for evaluating student's knowledge.  相似文献   

9.
Contents:
Plate 1. Glacial geomorphologic map of the area of Lago Puyehue and Lago Rupanco.
Plate 2. Glacial geomorphologic map of the Lago Llanquihue area.
Plate 3. Glacial geomorphologic map of the Seno Reloncaví area.
Plate 4. Glacial geomorphologic map of the northern sector of eastern Isla Grande de Chiloé.
Plate 5. Explanation of map units in Plates 1-4.
Plate 6. Location of radiocarbon sample sites and stratigraphic sections for Lago Puyehue and Lago Rupanco map sheet of Plate 1.
Plate 7. Location of radiocarbon sample sites and stratigraphic sections for Lago Llanquihue map sheet of Plate 2.
Plate 8. Location of radiocarbon sample sites and stratigraphic sections for Seno Reloncaví map sheet of Plate 3.
Plate 9. Location of radiocarbon sample sites and stratigraphic sections for Isla Grande de ChiloÄ(c) map sheet of Plate 4.  相似文献   

10.
Land cover type is a crucial parameter that is required for various land surface models that simulate water and carbon cycles, ecosystem dynamics, and climate change. Many land use/land cover maps used in recent years have been derived from field investigations and remote-sensing observations. However, no land cover map that is derived from a single source (such as satellite observation) properly meets the needs of land surface simulation in China. This article presents a decision-fuse method to produce a higher-accuracy land cover map by combining multi-source local data based on the Dempster–Shafer (D–S) evidence theory. A practical evidence generation scheme was used to integrate multi-source land cover classification information. The basic probability values of the input data were obtained from literature reviews and expert knowledge. A Multi-source Integrated Chinese Land Cover (MICLCover) map was generated by combining multi-source land cover/land use classification maps including a 1:1,000,000 vegetation map, a 1:100,000 land use map for the year 2000, a 1:1,000,000 swamp-wetland map, a glacier map, and a Moderate-Resolution Imaging Spectroradiometer land cover map for China in 2001 (MODIS2001). The merit of this new map is that it uses a common classification system (the International Geosphere-Biosphere Programme (IGBP) land cover classification system), and it has a unified 1 km resolution. The accuracy of the new map was validated by a hybrid procedure. The validation results show great improvement in accuracy for the MICLCover map. The local-scale visual comparison validations for three regions show that the MICLCover map provides more spatial details on land cover at the local scale compared with other popular land cover products. The improvement in accuracy is true for all classes but particularly for cropland, urban, glacier, wetland, and water body classes. Validation by comparison with the China Forestry Scientific Data Center (CFSDC)–Forest Inventory Data (FID) data shows that overall forest accuracies in five provinces increased to between 42.19% and 88.65% for our MICLCover map, while those of the MODIS2001 map increased between 27.77% and 77.89%. The validation all over China shows that the overall accuracy of the MICLCover map is 71%, which is higher than the accuracies of other land cover maps. This map therefore can be used as an important input for land surface models of China. It has the potential to improve the modeling accuracy of land surface processes as well as to support other aspects of scientific land surface investigations in China.  相似文献   

11.
以广州花城广场为案例,通过设计以认知地图、照片拍摄以及眼动实验环节的视觉研究方法,对花城广场的空间感知进行分析。结果表明:1)通过分析认知地图以及眼动数据可以发现,认知地图中高频率出现的要素和眼动实验得出的参与者感兴趣要素相一致,花城广场的建筑物、边界、场所和区域是参与者比较感兴趣的要素,以上要素在眼动实验中首次进入时间短,在认知地图中出现频率高;2)通过分析注视点注视时间热点图,可以得出在城市开敞空间的规划中应注重建筑物、构筑物、装置和场地的合理结合,注重空间层次和空间秩序,注重营造场所的规划设计结论。在应用上,照片拍摄、眼动实验等视觉的神经科学研究方法的使用可以为城市开敞空间的规划设计提供公众参与的新思路。  相似文献   

12.
The objective of this study is to develop a methodology to integrate multi-source remote sensing data into a homogeneous time series of land cover maps in order to carry out change detection. We developed a method to increase the comparability between land cover maps coming from panchromatic aerial photographs and SPOT XS (multi-spectral) data by equalizing their levels of thematic content and spatial details. The methodology was based on the hypotheses that: (1) map generalization can improve the integration of data for change detection purpose, and (2) the spatial structure of a land cover map, as measured by a set of landscape metrics, is an indicator of the level of generalization of that map. Firstly, the methodology for data integration was developed by using land cover maps generated from near-synchronous data. Results revealed that, by controlling successively the parameters that influence the level of map generalization, the percentage of agreement between the near-synchronous land cover maps can be increased from 42% to 93%. The computation of five landscape metrics for a set of generalized land cover maps and for the target map allowed us to optimize the level of generalization by measuring the similarity in landscape pattern of the maps. The optimum level of generalization of the land cover map obtained from the aerial photographs for comparison with a land cover map derived from SPOT XS data was found at a resolution of 41m for two generalization levels of the thematic content. The spatial structure of a land cover map, as measured by a set of landscape metrics, is thus a good indicator of the level of generalization of this map. Secondly, the method was applied by integrating a land cover map obtained from aerial photographs of 1954 with a land cover map obtained from a SPOT XS image of 1992.  相似文献   

13.
We bring up the issue related to the need and importance of undertaking an assessment of the present status of vegetation in Prebaikalia. The vegetation of this region has long been experiencing strong anthropogenic destructions, especially in the southern, more developed, areas. Anthropogenic impacts on vegetation continue to be enhanced thus influencing the processes of spontaneous development of vegetation and decreasing its ecological potential. Assessment of the present status of vegetation as a complex self-evolving autotrophic natural entity having its own evolutionary history of development and dynamical potential is used in reference to identifying and evaluating the degree of disturbance of its native (spontaneous) florocenotic structure. To improve objectivity of research results uses a cartographic method supported by GIS technologies. On the basis of the principles of a structural-dynamical classification of plant communities as suggested by V. B. Sochava, we compiled a universal geobotanical medium-scale (1:500 000) map for Prebaikalia. The map was generated for two purposes: inventory, i.e. identifying the typological belonging of existing plant communities in the region, and for assessment–dynamical purpose to identify the epitaxon structure of the entire vegetation cover. These efforts were accompanied by a formalized assessment of the age structure of tree stands of the region’s forest communities as well as a clear differentiation between forest and non-forest vegetation by identifying new burns and felling areas. The findings formed the basis for generating a detailed 1:500 000 map of disturbances to Prebaikalia’s vegetation displaying 11 kinds of vegetation disturbances ranging from the persisting native communities to those substituted by agrocenoses and introductions of urban settlements. A general outline of the present status of vegetation is provided as well as the main directions for nature management optimization in the region within the framework of the state ecological policy.  相似文献   

14.
2008年以来地图学眼动与视觉认知研究新进展   总被引:7,自引:0,他引:7  
地图是人类日常生活中不可或缺的工具。地图认知作为研究人对地图的感知、学习、记忆、推理和决策的科学,一直以来是地图学基础理论的重要内容。作为地图认知研究的核心,近年来地图视觉认知在相关学科(如心理学、认知科学和计算机视觉)和新的研究手段(如眼动跟踪、脑电和核磁)的促进下取得了一系列新的研究成果。尤其是眼动跟踪方法作为地图视觉认知研究的重要手段之一,越来越受到研究者的关注,为地图视觉认知研究的定量化、实用化提供了有力支撑。本文系统地梳理了2008年以来眼动跟踪方法在地图视觉认知研究中取得的新进展,并将其归纳为6个发展趋势,分别包括:① 刺激材料:从静态地图到动态交互地图;② 研究范围:从地图认知到地图空间认知;③ 实验环境:从实验室环境到真实环境;④ 地图维度:从二维地图到三维地图;⑤ 个体差异:从单一维度到多维度;⑥ 研究目的:从规律探究到实践应用。本文最后总结了未来研究面临的挑战、难点和可能的解决方法,期望能在地图视觉认知研究中起到抛砖引玉的作用。  相似文献   

15.
Viral maps—ones that are shared widely on social media and media outlets—have become an increasingly common part of online conversations about a range of issues. Despite the increasing prevalence of these viral maps, only a few academic researchers have examined the factors leading to their popularity or their social use and effect. In this article, we analyze two case studies of viral maps, a viral tweet about the August 2017 total eclipse and an interactive tool for exploring educational attainment by neighborhood in the United States. By reflecting on our experience as authors of these maps and analyzing the reactions they elicited, we identify several key elements of these maps and their circulation. First, viral maps act as a form of phatic communication, allowing users to restate and react to shared social identities. Second, maps are read from specific times and places, and this spatiotemporal context significantly shapes the reactions of map readers. Finally, viral maps illustrate gaps or improvements in trust between mapmakers and map readers, including questions about map accuracy or the intentions behind the map. We close by considering implications for future research and viral cartography. Key Words: online maps, social networks, viral cartography.  相似文献   

16.
The vegetation of Norway varies along three main gradients: from south to north, from the lowlands to the mountains, and inland from the coast. The underlying criteria used in preparing the enclosed new map of the vegetational regions of Norway in the scale 1:1.5 mill, are discussed, especially with regard to Central Norway. On the major maps of the vegetational zones of the Nordic countries so far published, Norway has received different treatment. A new zonal map based on the abovementioned regional map is presented and discussed. A coastal section is distinguished in the far west of Norway, and on the regional map this section is subdivided into three separate altitudinal belts. The remaining part of Norway is split into regions on the detailed regional map or into zones on the zonal map, as follows: nemoral, present only in the far south of Norway; boreonemoral, which extends north to the Trondheimsfjord; southern boreal, as far north as Salten; middle boreal, from the Østlandet area northwards up the major valleys into Central Norway and northeastwards to Alta in North Norway; northern boreal, up to the altitudinal (climatic) forest limit; and finally the low, middle and high alpine regions in the mountains. The vegetational regions of Central Norway are thereafter described in more detail and contour maps (isohypses) presented for the upper limits of the regions.  相似文献   

17.
人口密度空间化的一种方法   总被引:22,自引:2,他引:20  
人口密度空间化是地理学中一个重要的研究课题,但是传统方法直接生成的人口密度分布图具有不同区域间突变的缺点。该文中基于面积权重内插法与邻域平均法原理,以MapInfo为软件平台,在缺乏地形图、RS图片等资料的情况下,提出人口密度空间化的一种方法——网格单元面积权重内插法,并以丰县为研究区域进行例证。结果表明:该方法有效缓和了传统方法直接生成的人口密度图中的突变线,制作的人口密度Grid专题地图能够很好地反映人口密度的平均性,生成的人口密度三维可视化地图符合人口密度的空间分布特点。  相似文献   

18.
Hasholt, Bent: A new map of the Mitdluagkat glacier—a preliminary report. Geografisk Tidsskrift 87: 19–21, Copenhagen June 1987.

A new map covering the whole Mitdluagkat Glacier has been elaborated. The map is based on air photos from Geodetic Institute in scale 1:150,000 taken July 30, 1981. The scale of the new map is 1:20,000 with 10-m contour intervals. Preliminary field tests indicate that the map is so accurate that it might be used for comparative studies of long-term variations in mass balance of the glacier.  相似文献   

19.
The accuracy of old maps can hold interesting historical information, and is therefore studied using distortion analysis methods. These methods start from a set of ground control points that are identified both on the old map and on a modern reference map or globe, and conclude with techniques that compute and visualise distortion. Such techniques have advanced over the years, but leave room for improvement, as the current ones result in approximate values and a coarse spatial resolution. We propose a more elegant and more accurate way to compute distortion of old maps by translating the technique of differential distortion analysis, used in map projection theory, to the setting where an old map and a reference map are directly compared. This enables the application of various useful distortion metrics to the study of old maps, such as the area scale factor, the maximum angular distortion and the Tissot indicatrices. As such a technique is always embedded in a full distortion analysis method we start by putting forward an optimal analysis method for a general-purpose study, which then serves as the foundation for the development of our technique. Thereto, we discuss the structure of distortion analysis methods and the various options available for every step of the process, including the different settings in which the old map can be compared to its modern counterpart, the techniques that can be used to interpolate between both, and the techniques available to compute and visualise the distortion. We conclude by applying our general-purpose method, including the differential distortion analysis technique, to an example map also used in other literature.  相似文献   

20.
中国区域SRTM90m数字高程数据空值区域的填补方法比较   总被引:19,自引:0,他引:19  
本文对中国地区SRTM90m分辨率的数字高程数据的空值区域做了提取和分析,在此基础上尝试了4种内插填补的方法,并对各种处理方法的过程及结果做了比较,从而确定先从SRTM90m数据中直接提取等高线,再内插生成DEM,用内插出来的值填补原始数据的方法在目前较为适用。此外本文还提出了一些后期处理方法以完善数据。  相似文献   

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