Monitoring salt‐affected soils using remote sensing data

Proper management of salt‐affected soils for agriculture requires timely and reliable information on their nature, extent and distribution. Remote sensing data have been found to provide above mentioned information by virtue of spectral measurements of a large area taken at regular intervals. An attempt has been made in this study to map the salt‐affected soils of Mainpuri district of Uttar Pradesh during 1975 and 1986 period using Landsat‐MSS and TM data, respectively using visual interpretation techniques. The soils are saline‐sodic in nature and qualify as Typic Natrustalfs (USDA, 1975). A comparison of the areal extent of these soils during the above mentioned periods reveals a reduction of 7.7 percent from 1975 to 1986. This is due to reclamation of salt‐affected soils and also due to the adoption of appropriate soil and water management practices by the farmers which was confirmed during the ground truth collection.