Characterization and classification of soils on topo-sequence of Laterite landscape in tropical ecosystem of Goa

Abstract

Five typical pedons representing major laterite landscape in tropical ecosystem of Goa viz., flat topped hills, escarpments, conical hills, undulating hills and colluvial low lands under varying land use were studied for their morphological characteristics, physical and chemical properties, soil genesis and taxonomy. The soils were moderately to strongly acidic in reaction, very shallow to deep in depth Texture of the soils varied from gravelly sandy clay loam to gravelly clay loam on hills, while it varies from sandy loam to clay loam in undulating and colluvial low lands. The clay content, bulk density, AWC, organic carbon, cation exchange capacity, base saturation and exchangeable hydrogen and aluminium in the sols were ranged from 12.0 to 50.8 per cent, 1.37 to 1.53 Mg m-3 , 1.2 to 11.4 cm m-1 , 0.1 to 3.3 per cent, 3.9 to 12.4 cmol (p+) kg-1 , 21.9 to 66.5 per cent, 0.1 to 0.3 cmol (p+) kg-1 and 0.0 to 0.9 cmol (p+) kg-1 respectively. The soils had isohyperthermic temperature regime and ustic soil moisture regime. The soils were grouped under three soil orders viz., Entisols, Inceptisols and Alfisols and further classified into four families viz., Lithic Ustorthents, Lithic Haplustepts, Dystric Haplustepts and Kanhaplic Haplustalfs.