Delineation of boron status in Tirunelveli district of Tamil Nadu using GIS and GPS techniques

Abstract

A study was undertaken in Tirunelveli district of Tamil Nadu with a view to assess the Boron status of soils at block level. A sum of 1,798 geo-referenced surface soil samples from nineteen blocks of Tirunelveli district representing different soil units as per the soil map prepared on 1:50,000 scales was collected randomly at 0-15 cm depth using Global Positioning System. The soil samples were analysed for available hot water soluble boron and the hot water soluble boron content varied from 0.01to 5.52 mg kg-1 soil. Analytical results and the GPS data was used for the preparation of thematic maps showing spatial distribution of micronutrients status block wise in the district. Locations of soil sampling sites of Tirunelveli district were marked on base map on 1: 50,000 scales prepared from State Revenue Maps and digitized using Arc-info GIS. The delineation study thus clearly indicates that, the hot water soluble boron was found to be low in Pappakudi and Cheranmahadevi blocks and in rest of the blocks it exhibited medium to high status.