Effects of Different Land Use Types Managed By Smallholder Farmers on Soil Properties in Central Ethiopia

Abstract Background Aim: Land use change causes a remarkable change in soil properties. The nature of change depends on multiple factors such as soil type, type and intensity of land use, climate, and the like. This study investigated the variation in soil physicochemical properties across five common land use practices i.e., enset system, farmland, and grazing-land (closed and open), and Eucalyptus woodlots practiced on originally same soil type and comparable topographic and climatic settings.Methods: A total of 105 disturbed and undisturbed soil samples [5 treatments (land use types) *7 replications (household)* 3 soil depth layers: 0–15cm, 15–30 cm, 30–45cm] were collected for selected soil chemical and physical analyses. Standard soil analytical procedures were followed in carrying out soil analysis. To meet the assumptions of normal distribution and homogeneity of variances, soil data on available phosphors were log-transformed before statistical analysis was undertaken and reported after back transformation. Two way analysis of variable were used to investigate the effects of land use and soil depth and their interaction on soil properties and when the analysis showed a significant difference (p <0.05) among land use and soil depth men separation were made using Turkey’s pairwise comparisons.Results: There were significant differences in physical and chemical properties of soil across land use and soil depth categories. Enset system had significantly higher pH, available phosphorus (P), exchangeable potassium (K+), soil organic carbon (SOC), and total nitrogen (TN) and their stocks than other land use types. Enset fields had higher SOC (78.4%) and soil TN (75%), and SOC and TN stocks of (66%) and (58%), respectively than cereal farmland. This study had also revealed a less expected finding of higher soil organic carbon and total nitrogen under Eucalyptus wood than farm land. Soil carbon and total nitrogen stocks showed a decreasing trend of enset system> closed grazing-land > eucalyptus woodlot > open grazing-land > farmland 0-45cm.Conclusion: Overall, some land use systems (e. g. enset agroforestry) improve the soil biophysical and chemical properties, while others such as cereal production degrade the soil. Hence appropriate land and soil management intervention should be promptly adapted to mitigating the continuous loss of nutrient from the dominantly practiced cereal farm land through maintaining crop residues, manure, crop rotation and scaling up agro-forestry system.