Remote sensing technology based methods provides a cost-effective way to investigate soil conditions in inaccessible territories or direct field methods are expensive. Land degradation maps can be generated and are useful for planning soil conservation / reclamation programs, land use planning, for bringing additional areas into cultivation and also to improve productivity levels in degraded lands.
In India, Studies have been carried out in past to prepare soil maps at 1:25,000 and 1:12,500 scales in selected districts in the country. Several studies are carried out on pilot scale for preparation of soil maps at 1:10K scale required for Village level management of soils, delineation of homogeneous management zones for macro nutrient management, precision Agriculture in mono cropped agricultural systems Studies on Soil Carbon Dynamics was carried out as part of National Carbon Project which also provided key inputs to UNCCD towards national land neutrality targets.
Remote sensing based soil maps soils are generated through hybrid approach to address - the close relationship between physiography (landform), lithology, and vegetation type associated with the terrain and soils occurring thereon is utilized during mapping.
Satellite data from IRS sensors of India are being used to generate soil maps through monoscopic (non-stereoscopic) visual interpretation and computer-assisted digital analysis approaches. In visual Interpretation approach, the close relationship between physiography (landform), lithology, and vegetation type associated with the terrain and soils occurring thereon is utilized during mapping. From the soil resources map, the derivative information like land capability, irritability and suitability are assessed using supportive thematic information.
Satellite-based spectral indices, such as Normalized Difference Vegetation Index (NDVI), Normalized Difference Soil Index (NDSI), Tasselled Cap Transformation (TCT), along with Linear Spectral Unmixing Analysis (LSMA) can also be used for the estimation and evaluation of soil erosion processes/status, to investigate soil exposure and assess soil properties
Land Degradation Mapping, Soil health card (for promoting Integrated Nutrient Management through judicious use of chemical fertilizers including secondary and micro nutrients in conjunction with organic manures and bio-fertilizers for improving soil health), soil salinity, Prediction of Soil Organic Carbon content.
