Characterizing soils of Delbo Wegene watershed, Wolaita Zone, Southern Ethiopia for planning appropriate land management.

Abstract

The soils of the Delbo Wegene watershed of Southern Ethiopia were characterized along toposequence for the development of land management plan for sustainable soil management practices. Four pedons along toposequence were studied. Delbo Wegene watershed is located between 06°52’ 45.9’’ and 06°53’34.8’’ N latitude and between 37°48’ 10.5’’ and 37°48’42.4’’E longitude, with altitude ranging from 2100 to 2300 m.a.s.l. The soils were generally dark reddish brown to very dark brown and very deep (> 150 cm). The overall friable consistency, low bulk density (1.0 to 1.26 gm/cm3), sub angular to angular blocky structure, high total porosity (53 to 61%) indicated that the soils have good physical condition for plant growth. The soils were slightly (pH: 5.8) to moderately acidic (pH: 6.4). Organic carbon content, available micronutrients and cation exchangeable capacity of the soils decrease with soil depth. However, exchangeable cations increase with increasing soils depth. Available phosphorus content of the soils ranged from very low to high. However, available Cu content of the soils were marginal to deficient. The upper and middle pedons with argilic subsurface horizons were classified as Typic Paleustults (Soil Survey Staff, 1999). These soils correlate with Cutanic Luvisols (WRB, 2006). The lower and toe slope pedons with mollic epepedon and cambic subsurface horizon were classified as Typic Haplustepts. These soils correlate with Haplic Cambisols (WRB, 2006). The result indicated that the distribution and properties of the soils vary along the toposequence in the watershed. Key words: Soil characteristics, soil classification, Delbo-Wegene watershed