Soil Characterization and Land Suitability Evaluation to Cereal Crops in Yigossa Watershed, Northwestern Ethiopia

Abstract

A study was conducted in 2013 at Yigossa watershed, Northwestern Ethiopia to characterize the soils using FAO criteria and evaluate their suitability to cereal crop producton. Surface soil samples from different soil types were collected and analyzed in the soil laboratory of Amhara Design and Supervision Works Enterprise. The collected soils were analyzed for soil pH, organic matter, total N and available P. FAO guideline was used to evaluate the land suitability for selected cereal crops and geographical information system (GIS) was employed to analyze and map the soils within the watershed. Results indicated that the soils of the watershed were dominantly slightly acidic to slightly alkaline with pH ranging from 5.60 to 7.87. The organic matter content ranged from 1.88% in Nitisols to 3.56% in Gleysols and Regosols; while the total N content ranged from 0.09% in Nitisols to 0.18% in Gleysols and Regosols. Available P contents varied from 1.78 mg kg-1 in Nitisols to 12.3 mg kg-1 in Regosols. Analysis of land suitability analysis showed that 60.9% of Nitisols, 38.2% of Gleysols, 36.1% of Luvisols and 23.4% of Regosols were moderately suitable for maize (Zea mays L.); while 32.5% of the Nitisols, 50.6% of Gleysols, 73.0% of Luvisols and 73.9% of Regosols were moderately suitable for finger millet (Eleusine coracana L.). Moreover, 51.4% of Nitisols, 38.2% of Gleysols, 68.7% of Luvisols and 60.2% of Regosols were moderately suitable for teff (Eragrostis tef Zucc.); whereas 32.5% of Nitisols, 50.6% of Gleysols, 73.0% of Luvisols and 73.8% of Regosols were moderately suitable for rice (Oryza sativa L.). From the result of the study it was possible to conclude that different soils are variably suitable for different crops. In some cases, the same soil could be suitable for different crops bringing competing nature of crop land use types for the same parcel of land. However, yield per unit of land and return to investment dictates farmers’ decision on land allocation for a particular use.