Effect of integrated soil bunds on key soil properties and soil carbon stock in semi-arid areas of northern Ethiopia

Abstract

Land degradation is a serious global problem. To reclaim degraded land, many soil bunds have been implemented. However, their effectiveness has not been studied in all regions of Ethiopia. The objective of this study was to investigate the effect of soil bunds integrated with tree fodder species on selected soil properties and carbon stock in semi-arid areas of northern Ethiopia. Twenty-seven composite soil samples were collected from 20 cm depth. The soil parameters texture, soil organic matter (SOM), total nitrogen (TN), pH, cation exchange capacity (CEC), available phosphorus (Av.P) and available potassium (Av.K) were analysed. Statistical analyses were performed using one-way ANOVA and mean comparisons were made using Tukey’s honestly significant difference test. Mean values of SOM (2.13%, 1.47% and 0.85%), CEC (150.42, 100.58 and 80.68 cmol kg⁻¹ soil), TN (0.2, 0.14 and 0.08%), Av.P (7.08, 6.03 and 4.36 ppm), Av.K (1.52, 1.34 and 1.27 cmol kg⁻¹ soil), soil carbon stock (SCS; 12.48, 10.47 and 4.7 t ha⁻¹) and soil bulk density (BD; 1.35, 1.43 and 1.44 g m⁻³) were recorded in soil bunds integrated with forage species (ISB), soil bunds alone (SB) and non-conserved cultivated land (NC), respectively. The BD, SOM, CEC, TN and SCS showed a significant difference among the three cropland treatments and Av.P showed a significant difference only between (ISB and SB) and NC. The pH showed no significant differences and Av.K showed no significant difference between SB and NC. The findings indicate that integrating soil bunds with forage species was a better option to improve soil properties than soil bunds alone.