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SRTM DEM dataset in China (2000)

The SRTM sensor has two bands, namely C-band and X-band. The SRTM we are using now comes from the C-band. The publicly released SRTM digital elevation products include DEM data at three different resolutions:     * SRTM1 covers only the continental United States, with a spatial resolution of 1s;     * SRTM3 data covers the world with a spatial resolution of 3s. This is the most widely used dataset. The elevation reference of SRTM3 is the geoid of EGM96 and the horizontal reference is WGS84. The nominal absolute elevation accuracy is ± 16m, and the absolute plane accuracy is ± 20m.     * SRTM30 data also covers the world, with a resolution of 30s. There are multiple versions of SRTM data. The early SRTM data was completed by NASA's "JPL" (Jet Propulsion Laboratory) ground data processing system (GDPS). The data is called SRTM3- 1. The National Geospatial Intelligence Agency has further processed the data, and the lack of data has been significantly improved. The data is called SRTM3-2. This dataset is mainly the fourth version of SRTM terrain data obtained by CIAT (International Center for Tropical Agriculture) using a new interpolation algorithm. This method better fills the SRTM 90 data hole. The interpolation algorithm comes from Reuter et al. (2007). The data of SRTM is organized as follows: every 5 latitude and longitude grids is divided into a file, which are divided into 24 rows (-60 to 60 degrees) and 72 columns (-180 to 180 degrees). The file naming rule is srtm_XX_YY.zip, where XX indicates the number of columns (01-72), and YY indicates the number of rows (01-24). The resolution of the data is 90 m. Data use: SRTM data uses a 16-bit value to represent the elevation value (-/ + / 32767 meters), the maximum positive elevation is 9000 meters, and the negative elevation (12,000 meters below sea level). -32767 standard for empty data.

2020-04-08

Primary road network dataset of QinghaiLake River Basin (2000)

The data is a dataset of road distribution in Qinghai Lake basin, scale1: 250,000, projection: latitude and longitude, mainly including the spatial distribution and attribute data of main roads in Qinghai Lake basin, attribute fields: code (road code), name (road classification).

2020-04-07

The map of desert distribution in 1:2,000,000 in China (1974)

Desertification is a kind of land degradation with aeolian sands as the main symbol caused by the uncoordinated human-land relationship in arid, semi-arid and some semi-humid regions of northern China. Data source: edited by the China Institute of Glacial and Frozen Desert and coordinated by the Institute of Geography of the Chinese Academy of Sciences. Based on aerial photographs from the 1970s and field research, a 1: 2 million desert map was drawn. Mapping of the 14 million "Map of the People's Republic of China" published in 1971. First, the data set content 1.Desert_Ch_2009 (desert distribution) 2.Dune_hight_Ch_200 (dune height) 3.Gobi_Ch_200 (Gobi) 4.Wind_eroded_land_Ch_200 (wind erosion data) The fields of the desertification attribute table are as follows: (1) Semifixed (semi-fixed dunes): undulating sandy land (2-1), thicket dunes (2-2), parabolic dunes (2-3), beam nest dunes (2-4), sand ridges And dendritic sand ridge (2-5), honeycomb sand dune (2-6), honeycomb sand ridge (2-7), composite sand ridge (2-8) (2) Fixation (fixed dune): flat sandy land (3-1), grassland bush (3-2), sand ridge (3-3), honeycomb sand dune (3-4) (3) Migratory: Crescent sand dunes and dune chains (1-1), Crescent sand ridges and dunes (1-2), Lattice dunes and Lattice dune chains (1-3), Fish scales Sand dunes (1-4), feathery dunes (1-5), pyramid dunes (1-6), composite dunes and dune chains (1-7), composite dunes (1-8), composite Dome-shaped dunes (1-9), chain-shaped sand hills (sand dunes) (1-10), stacked chain-shaped sand hills (1-11), compound ridge-shaped sand hills (1-12), composite chain-shaped Sand Mountain (1-13), Pyramid Sand Mountain (1-14) (4) class_id: encoding of desertification attributes Projection information PROJCS ["Albers", GEOGCS ["GCS_Beijing_1954", DATUM ["Beijing_1954", SPHEROID ["Krasovsky_1940", 6378245.0,298.3]], PRIMEM ["Greenwich", 0.0], UNIT ["Degree", 0.0174532925199433]], PROJECTION ["Albers_Conic_Equal_Area"], PARAMETER ["False_Easting", 0.0], PARAMETER ["False_Northing", 0.0], PARAMETER ["longitude_of_center", 105.0], PARAMETER ["Standard_Parallel_1", 25.0], PARAMETER ["Standard_Parallel_2", 47.0], PARAMETER ["latitude_of_center", 0.0], UNIT ["Meter", 1.0]]

2020-04-07

The map of aeolian landform in Taklimakan desert (1978)

Ⅰ. this data Compilation: Lanzhou Desert Research Institute, Chinese Academy of Sciences Publication: Map Publishing House, Map Printing House Issue: Xinhua Bookstore Beijing Publishing House Ⅱ. The 1: 1.5 million Taklimakan Desert Aeolian Landform Map includes: 1. aeolian _ landform _ taklimakan _ 150 (aeolian landform) 2, height (dune height) 3, lake (lake) 4river1, 2, 3 (river), 5, road1, 2, 3 (road) Ⅲ. aeolian landform attribute fields: Aeolian_c (attribute), Aeolian_ (English control), Code (attribute code) Classification codes of geomorphic data attributes are as follows: (a), sand landform types 111. Ridge-shaped Compound Sand Mountain 112. Compound crescent dunes and dune chains 113. Pyramid dunes 114. Crescent dunes and dune chains 115, lattice sand dune and lattice sand dune chain 116, wind erosion residual hills 117. Compound Sand Ridge 118. Dome dunes 119. Fish Scale Sand Dunes 120, crescent sand ridges and linear sand ridges 121, red willow sandbags 122. Gobi (b) Sand dune height types 211, less than 10 meters 212, 10-25m 213, 25-50m 214, 50-100m 215, more than 100 meters (3) Other types 311, woodland and shrub forest 312. Artificial Oasis 313. Saline-alkali Land and Swamp Iv. projection information: Angular Unit: Degree (0.017453292519943295) Prime Meridian: Greenwich (0.000000000000000000) Datum: D_Beijing_1954 Spheroid: Krasovsky_1940 Semimajor Axis: 6378245.000000000000000000 Semiminor Axis: 6356863.018773047300000000 Inverse Flattening: 298.300000000000010000

2020-04-07

Dataset of IWEMS (Integrated Wind-Erosion Modelling System) in the Kubuqi Desert

I. Overview This data set contains the terrain data, soil data, meteorological data, land use data, NDVI data, etc. required for the operation of the IWEMS model. All maps and relevant point coordinates (weather stations) use the isometric projection UTM / WGS94 coordinate system. Ⅱ. Data processing description All maps and related point coordinates (weather stations) use the isometric projection UTM / WGS84 coordinate system. Ⅲ. Data content description The data content mainly includes: The basic terrain data includes the Cuneiform Desert (DEM) and the river network. The river network is used as the boundary for wind and sand transmission. The size of the DEM grid is 250 * 250 m. The river network was extracted using the ASTER-GDEM terrain data with the river burning method. Soil data, including soil physics, chemistry, and spatial distribution of soil types. It is derived from 1: 1 million soil database of China and converted to ESRI-grid format with a grid size of 250 * 250 m. Meteorological data, including daily data from Baotou, Dongsheng and Linhe meteorological stations around the Kubuqi Desert, from 2002 to 2010. Includes precipitation, wind speed and wind direction data. Land use data, 2000 land use data, scale is 1: 100,000. Convert it to ESRI-grid format with a grid size of 250 * 250 m. Ⅳ. Data usage description Evaluate wind and sand hazards along the Yellow River, estimate the amount of wind and sand entering the upper reaches of the Yellow River, and provide data support for establishing an early warning system for wind and sand hazards in the region.

2020-04-07

The resident site distribution dataset of the north slope of Tianshan River Basin (2000)

The data is the resident site distribution dataset of the north slope of Tianshan River Basin, including the hierarchical distribution of cities, counties, towns and villages at the north slope of Tianshan River Basin. The data mainly has two attribute fields: Code (residential area code) and Name (residential area name).

2020-04-07

River network dataset of the north slope of Tianshan River Basin (2000)

The data is the river dataset of the north slope of Tianshan River Basin. It is revised according to the topographic map and TM remote sensing image. The scale is 250,000, and the projection is latitude and longitude. The data includes spatial data and attribute data, attribute data fields: HYD_CODE (river code), Name (river name), SHAPE_ leng (river length).The data includes spatial data and attribute data. , SHAPE_leng (river length).

2020-04-06

Lakes dataset in the north slope of Tianshan River Basin (2000)

The dataset is a lake distribution map of the north slope of Tianshan Mountain Basin, with a scale of 250,000. The projection is latitude and longitude. The data includes spatial data and attribute data. The attribute fields of the lake are NAME (name of the lake) and CODE (lake code).

2020-04-06

Administrative division in the north slope of Tianshan River Basin (2000)

The dataset is a vector map of administrative boundaries of rivers in the north slope of Tianshan Mountains, with a scale of 250,000, projection: longitude and latitude, data includes spatial data and attribute data, and attribute fields: Name (name of county boundary) and Code (administrative code).

2020-04-06

Primary road network dataset of north slope of Tianshan River Basin (2000)

The data is the road distribution dataset of the river basins at the north slope of the Tianshan Mountains, with a scale of 250000 and a projection of latitude and longitude, including the spatial distribution and attribute data of the main roads in the river basins at the northern foot of the Tianshan Mountains, with attribute fields of code (road code) and Name (road classification).

2020-04-06