{"id":"12e91073-0181-44bf-8308-c50e5bd9a734","title":"中国数字高程图（1KM）","title_en":"Digital elevation model of China (1KM)","serial":"","user_limit":"为尊重知识产权、保障数据作者的权益、扩展数据中心的服务、评估数据的应用潜力，请数据使用者在使用数据所产生的研究成果中（包括公开发表的论文、论著、数据产品和未公开发表的研究报告、数据产品等成果），明确注明数据来源和数据作者。对于转载（二次或多次发布）的数据，作者还须注明原始数据来源。","instructions":"数据分为Albers和Geo文件夹，数据命名：chdem_105、chdem_Slope、chdem_Aspect、chdem_hillshade\n可以用arcgis、Qgis等遥感软件打开","description":"DEM是数字高程模型的英文简称(Digital Elevation Model)是流域地形、地物识别的重要原始资料。DEM 的原理是将流域划分为m 行n列的四边形(CELL)，计算每个四边形的平均高程，然后以二维矩阵的方式存储高程。由于DEM 数据能够反映一定分辨率的局部地形特征，因此通过DEM 可提取大量的地表形态信息，这些信息包含流域网格单元的坡度、坡向以及单元格之间的关系等。同时根据一定的算法可以确定地表水流路径、河流网络和流域的边界。因此从DEM 提取流域特征，一个良好的流域结构模式是设计算法的前提和关键。\n高程数据图是根据中国1:25万等高线和高程点形成的1km数据，包括DEM、山影（hillshade）、坡度（Slope）、坡向（Aspect）图\n数据集投影：\n两种投影方式 ：\n正轴割圆锥等面积投影 Albers Conical Equal Area（105、25、47)\n大地坐标WGS84坐标系","doi":"","projection":null,"language":"zh","share_type":"offline","east":135.5,"west":73.2,"south":17.8,"north":53.9,"scale":null,"crs":null,"filesize":977.0,"share_policy":"b","ts_created":"2019-06-29T06:32:14.998304+08:00","doi_type":null,"ts_updated":"2021-04-24T11:28:07.131531+08:00","time_description":"2000","datas_group":0,"time_description_en":null,"data_format":null,"project":[10,11],"specials":["1832ecb3-70d0-4b5e-bdb5-2e9ff4ad1efe","f2a78cde-1c98-4241-94dc-7532eba32b80"],"cite":null,"review_status":5,"review_invite":[{"user_name":"王卷乐","username":"王卷乐","email":"wangjl@igsnrr.ac.cn","is_cancel_expert":false}],"review_editor":{"id":21057,"last_login":"2022-04-02T11:43:37.753860+08:00","username":"gecm","email":"gechm@lzb.ac.cn","is_active":true,"is_staff":true,"user_name":"盖春梅"},"data_sources":"","temporal_resolution":"","spatial_resolution":"km","license":"Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0)","fund":[6],"subtopics":{"metadata":"12e91073-0181-44bf-8308-c50e5bd9a734","three_pole":null,"third_pole":null},"username":"盖春梅","review_time":"2019-06-29T12:20:06.922264+08:00","protected_duration":null,"protected_describe":null,"is_important":true,"hit_count":22828}