Assessment of Catchment Hydrology and Soil Fertility Under Different Land Use Systems in Fagita Lekuma District, Ethiopia

Abstract

Acacia decurrens plantations in the Timble-Faguita-Lekma watershed are being actively expanded to accommodate various land uses, mainly to produce charcoal and construction. This study aimed to investigate the effects of various land-use types on the hydrology of a watershed and the physicochemical characteristics of soils. Experiments comprised soil depth (0-15 cm and 15-30 cm) and land cover type (arable land, pasture, 0, 2, and 4-year stand). A 5*2 factorial array of randomized complete block designs (RCBD) with 4 replicates made up the design. The physicochemical parameters of the selected soils were investigated using 40 (5*2*4) composite soil samples. A semi-structured questionnaire and a two-way analysis of variance (ANOVA) were used to investigate selected farmers' perceptions of watershed hydrology. The results revealed that soil particle size (sand, silt, clay) and SOC concentration differed significantly across all land-use types and soil depths studied. Soil pH did not alter with depth (p<0.5605). At 4 years of age, wet aggregate stability (WAS), weight mean diameter (MWD), and geometric mean diameter (GMD) values were significantly different and greater. Two zero-year-old lines from an acacia decurrens plantation (p=0.0264, p<0.0001, and p<0.0161, respectively). Furthermore, WAS, MWD, and GMD scores are highly positively connected with grade (Tone p<0.0096, r=0.83 and SOC p<0.0001, r=0.85). Most households believe that recent land-use adjustments in their acacia decurrens plantations have reduced the severity of soil erosion.

Keywords

• catchment hydrology
• land use
• soil aggregate stability
• soil properties