Soil Characterization and Classification in Semi-Arid Regions of Varathuru Watershed, Andhra Pradesh, India

Abstract

Eight typical pedons representing Varathuru watershed of Chittoor district, viz Pachigunta (P1 and P2), Kalepalli (P3 and P4), Ramapuram (P5 and P6) and Oogguvaripalli (P7 and P8) in semi-arid ecosystem were studied for morphological, physical, chemical characteristics and their classification. Results indicated that, the colour of the soils varied from dark reddish brown to strong brown with sandy loam to sandy clay loam texture. These soils were slightly acid to moderately alkaline (6.03 to 8.35) in reaction and non-saline (0.02 to 0.36 dSm-1). The bulk density, water holding capacity, particle density, organic carbon (OC), cation exchange capacity (CEC) and base saturation were varied from 1.34 to 1.61 Mgm-3, 28.44 to 48.96%, 2.24 to 2.58 Mgm-3, 0.09 to 0.74%, 3.68 to 20.32 cmol (p+) kg-1 and 51.61% to 91.86%, respectively. Due to the presence of ustic soil moisture regime, isohyperthermic temperature regime and low organic matter content, the soils were classified into Typic Hapustepts (Pedons 2, 3, 4, 6 and 8), Typic Haplustalfs (Pedons 1and 7) and Ultic Haplustalfs (pedon 5).