Overview of iXGIS Data Download Tools and Data Resources

In iXGIS, features directly related to downloading data are mainly located under Data Management Tools in the Analysis Toolbox. The three commonly used tools are:

• Satellite Imagery Download Tool
• Surface Data Download Tool
• Administrative Boundary Download Tool

These three tools have clear roles: one downloads basemaps, one downloads thematic rasters, and one downloads administrative boundaries. Many users may find the names a little confusing at first, but in practice you can choose based on the result you want to obtain.

Tool Overview

Tool	Main Purpose	Output Type	Typical Data	Best For
Satellite Imagery Download Tool	Downloads online map tiles and mosaics them	GeoTIFF raster	Tianditu imagery, vector basemap, terrain hillshade, global boundaries	Basemaps, archiving, offline browsing
Surface Data Download Tool	Downloads preconfigured base raster datasets	GeoTIFF raster	NDVI, land cover, soil, terrain, evapotranspiration, and more	Raster analysis, thematic mapping, indicator calculation
Administrative Boundary Download Tool	Downloads administrative boundaries	Vector file	Provincial, municipal, and county or district administrative boundaries	Clipping boundaries, zonal statistics, administrative unit preparation

If you only want to create a background map, start with the Satellite Imagery Download Tool. If you need rasters that can be used directly in analysis, the Surface Data Download Tool is usually the right choice. If you need administrative boundary polygons, use the Administrative Boundary Download Tool.

Satellite Imagery Download Tool

This tool essentially saves an online basemap as a local GeoTIFF. It does not download raw remote sensing data. Instead, it downloads already rendered online tiles and automatically mosaics them into an output file.

According to the current help documentation, the common layers in the interface are Tianditu-related layers:

• Vector basemap (without labels / with labels)
• Imagery basemap (without labels / with labels)
• Terrain hillshade
• Global boundaries

There are several points worth clarifying first:

• The download result is an RGB raster suitable for display, comparison, and map production, not editable vector features.
• The tool works with Tianditu TileMatrixSet = w, which corresponds to Web Mercator EPSG:3857.
• The larger the area and the higher the zoom level, the more tiles are required and the longer the download takes.

This tool is therefore better suited for tasks such as:

• Preparing a stable offline basemap for a project
• Comparing current project data with an online basemap
• Preparing background imagery or road network labels before thematic map production

Related article:

• Satellite Imagery Download Tool Guide

Administrative Boundary Download Tool

This tool retrieves boundary data from the Tianditu administrative region API and outputs a vector file. Unlike the basemap download tool above, it produces polygon features that can be used directly for clipping, statistics, or overlay analysis.

According to the current documentation, the tool supports step-by-step selection by administrative level:

• Province
• City
• County or district

The output usually includes these fields:

• gb: administrative division code
• pgb: parent administrative division code
• name: administrative region name
• level: administrative level
• center_lng / center_lat: center point coordinates

The coordinate reference system is EPSG:4490, which is the CGCS2000 geographic coordinate system.

The three most common uses of this tool are:

• Quickly downloading administrative boundaries for a project area
• Using the boundaries as raster clipping extents or statistical zones
• Joining business tables by administrative region code

Related article:

• Administrative Boundary Download Tool Guide

Surface Data Download Tool

This tool is the easiest one to misunderstand. "Surface data" here does not refer only to land surface data in the narrow sense. It is a unified download entry for a set of base raster datasets in the platform. Typically, you select a data type first, then choose a source, year, or version, and finally export a GeoTIFF by area.

Based on the current help documentation, several commonly used data categories have already been organized in this tool.

Downloadable Data

1. Vegetation Index Data: NDVI

The documentation explicitly mentions annual NDVI data.

• Landsat 8 NDVI
  • Data source: Microsoft Planetary Computer landsat-c2-l2
  • Platform filter: landsat-8
  • Spatial resolution: 30 m
  • Result format: annual average NDVI
• Sentinel-2 NDVI
  • Data source: Microsoft Planetary Computer sentinel-2-l2a
  • Spatial resolution: 10 m
  • Result format: annual average NDVI

This type of data is generally used for vegetation cover change, regional comparison, or preliminary assessment of ecological conditions.

2. Land Cover Data

The land cover section is currently the most complete and already lists several common public data sources.

• ESA WorldCover
  • Resolution: 10 m
  • Coverage: global
  • Years: the current documentation lists 2020 and 2021
  • Characteristics: high resolution, suitable for interpreting current land cover conditions
• GlobeLand30
  • Resolution: 30 m
  • Years: 2000, 2010, 2020
  • Current platform note: downloads are currently available for China
  • Characteristics: a mature Chinese product system, suitable for domestic regional applications
• MODIS MCD12Q1
  • Resolution: approximately 500 m
  • Time range: annual series
  • Characteristics: long time span, suitable for long-term change analysis

If resolution is more important, WorldCover or GlobeLand30 is usually the first choice. If multi-year change matters more, MODIS is often easier to use.

For more information, see:

• Land Use Data Download and Usage Guide

3. Soil Data

The soil dataset explicitly mentioned in the current help documentation is HWSD v2. This type of data is generally not just a single-band result. Instead, it is organized by soil attribute and depth layer.

According to the documentation, common cases include:

• Downloadable parameters such as clay, sand, silt, organic carbon, and calcium carbonate
• Typically 7 depth layers
• Output is usually a multiband raster, with different bands corresponding to different soil layers

This type of data is better suited for soil attribute analysis or as base input for ecological and agricultural environment topics.

4. Terrain Data

The current documentation lists two terrain datasets:

• ASTER GDEM v3
• AW3D30 DSM

Both are base elevation datasets. Common use cases include:

• Terrain analysis
• Slope and aspect calculation
• Hillshade analysis
• Data preparation before hydrological analysis

If you only need to prepare elevation data for a project area, this tool is much more convenient than downloading tiles manually and mosaicking them yourself.

5. Climate and Meteorological Data

The example given in the current help documentation is the MODIS annual evapotranspiration product:

• Example product: MOD16A3GF.061
• Example layer: ET_500m
• Resolution: approximately 500 m
• Temporal resolution: annual

This type of data is commonly used as background indicators in ecology, hydrology, or regional assessment.

Tianditu Administrative Regions

Administrative region vector data usually includes these fields:

• gb: administrative division code
• pgb: parent administrative division code
• name: administrative region name
• level: administrative level
• center_lng / center_lat: center point coordinates

The coordinate reference system is EPSG:4490, which is the CGCS2000 geographic coordinate system.

What to Check Before Use

Although the workflow has been simplified, it is still recommended to confirm the following points before using the data in a project:

• Whether you need a rendered basemap or an analysis-ready raster
• Whether the data coordinate reference system matches the project CRS
• Whether the resolution meets the business scale requirements
• Whether the data coverage is global, China-wide, or limited to a local area
• Whether the year and version meet the project's temporal requirements

The simplest way to decide can be summarized in three sentences:

• For display basemaps, use the Satellite Imagery Download Tool.
• For raster analysis, use the Surface Data Download Tool.
• For administrative clipping and zonal statistics, download administrative boundaries first.

Related documentation:

• Satellite Imagery Download Tool Guide
• Surface Data Download Tool Guide
• Administrative Boundary Download Tool Guide