Evaluation of Soil Fertility Status and Soil Carbon Stock Under Acacia Abyssinica -Based Parkland Agroforestry Practice in Borena District, Amhara Regional State, Ethiopia

Parkland agroforestry is one of the oldest traditional practices characterized by planting scattered trees on farmland for socio-economic and cultural purposes. In Ethiopia, there are limited studies that emphasize the impact of Acacia Abyssinica agroforestry practices on soil fertility and climate change mitigation. The study was conducted in Borena District of Amhara Regional State, Ethiopia, to evaluate the impact of Acacia Abyssinica -based parkland agroforestry on soil fertility and carbon stock potential. A mixture of purposive and random sampling techniques were employed to select sample kebeles. 54 soil samples were collected from sample Acacia Abyssinica at half of the tree canopy, edge of the canopy, and 5 meters away from the canopy edge. The results showed that organic carbon percentage and soil organic carbon stock were significantly and positively affected (p < 0.05) by both main effects and interaction effects. The highest mean values of organic carbon (2.23) and soil organic carbon stock (75.037) were recorded at a soil depth of 0–30 cm at half of the tree canopy, while the lowest mean values were observed at a soil depth of 30–60 cm at 5 meters away from the canopy edge. Bulk Density, Total Nitrogen, Available Water Content, available Phosphorus, Cation Exchange Capacity, Exchangeable Potassium and Magnesium were significantly influenced (P < 0.05) by distance from the tree and soil depth. The study uncovered the environmental contribution of Acacia Abyssinica though further studies are required to explore how and why farmers maintain the trees on farmlands and their divers economic, social and environmental contribution.