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PRINT ISSN : 2319-7692
Online ISSN : 2319-7706 Issues : 12 per year Publisher : Excellent Publishers Email : editorijcmas@gmail.com / submit@ijcmas.com Editor-in-chief: Dr.M.Prakash Index Copernicus ICV 2018: 95.39 NAAS RATING 2020: 5.38 |
An investigation was carried out to characterize and classify soils of different land uses of lower Brahmaputra valley of Assam. Seven soil profiles were collected from a contiguous area under acacia (P1), bamboo (P2), coconut (P3), sisoo (P4), teak (P5), paddy (P6) and jackfruit (P7) land uses at Horticultural Research Station, Kahikuchi. The soils under different land uses varied in morphological, physical and chemical properties. The hue of the soil was 10YR, value ranged from 5-7 and chroma varied from 2-8. Few, fine, faint to many, coarse, prominent mottles with colours of 7.5YR 6/8 to 7.5YR 7/8 were observed in the subsurface horizons of all the studied land uses. Few to abundant Fe-Mn glaebules were observed in the subsurface horizons of P2 (bamboo), P5 (teak) and P6 (paddy). Soil textural classes varied from sandy clay loam to clayey and the structure was sub angular blocky except in surface horizon of P6 (paddy). The clay content increased with soil depth which indicated fairly development of the soils. Soil organic carbon was highest in the surface horizon of a profile and it decreased regularly with soil depth. Bulk density of the soils varied from 1.31 to 1.47 Mgm-3 and particle density varied from 2.40 to 2.61 Mgm-3. The soil pH was found to be in acidic range (4.7-5.8) and the EC was low (0.01 to 0.09 dSm-1). Free oxides of Fe and Al increased down the profile. Exchangeable Ca2+ was the dominant basic cation followed by Mg2+, K+ and Na+. Exchangeable Al3+ was dominant acid cation. The CEC and ECEC of the soils were low varying from 5.18 to 10.3 cmol (p+) kg-1 soils and 2.97 to 5.32 cmol (p+) kg-1 soils respectively. The base saturation of the soils varied from 35.9– 57.2%. On the basis of morphological, physical and chemical properties, the soils of the study area were classified as Typic Dystrudepts except P6 (paddy) which was classified as Aeric Dystrudepts.