Application of Geotechnics in Soil Survey and Land Evaluation

Extensive and reliable information on soil and land resources are prerequisites for efficient and effective management planning of these vital natural resources. The information on soils with regard to their nature, physico-chemical characteristics and spatial distribution is of paramount importance in formulating any optimal land use plan. Generation of large-scale spatial database on soil and land resources by conventional method is a time consuming and highly expensive process. The application of Remote Sensing Technology has been universally recognized as a highly effective and inevitable tool for soil resource mapping and watershed management. Indian Remote Sensing Satellite (IRS) data are being extensively used for soil resource-mapping purposes. It is found to be superior over topographical map for soil mapping. The Standard False Color Composite (FCC), satellite imagery on 1:50,000 scale widely being used for soil resource inventory in semi-detail and reconnaissance survey (Karale et al. 1991).  However, with the availability of  high  resolution PAN (5.8 m) and LISS III (23 m) data from IRS-1C/1D satellites and multispectral high resolution (5.8 m) data from Resourcesat (IRS- P6) satellite , it is now possible to utilize these data for large-scale soil mapping, i.e. up to 1:12,500 scale for village-level  planning. Cartosat-1 with 2.5 m spatial resolution and Cartosat-2 satellites (to be launched) with better than 1 m spatial resolution will be quite useful to generate larger scale soil maps.