Landsat satellite data, provided by the U.S. Geological Survey, have proven useful for studying the effects of natural and anthropogenic change to the land surface of the planet.
Nevertheless, individual Landsat images are also useful for studying and measuring land units in areas removed from easy access. A good example of the value of Landsat for observing such areas is the Selenge River delta near the border between Russia and Mongolia. The Selenge River bisects northern Mongolia and provides water for the Mongolian .breadbasket,. a region of gently rolling hills and the source of wheat crops for the region. Adjacent to the delta, as the river feeds Lake Baikal, are recently cultivated agricultural fields (noted by the geometric patterns) and lowland shrubs and grasslands. The maze of blue tones identifies the channels as the river covers low lands and swamps.
The Landsat data are used by regional planners to study the spread of the delta, the effects of river drying on adjacent crop lands, and the river flow into the lake.