SOIL CHARACTERIZATION AND PHYSICAL LAND SUITABILITY EVALUATION FOR RAINFED MAIZE AND TEF CROPS PRODUCTION AT WOLKITE UNIVERSITY AGRICULTURAL FARM GURAGHE ZONE, ETHIOPIA

Abstract

For precision agriculture, land use planning, and management, the major information sources are soil characterization, classification, and land suitability evaluation. The study was conducted at Wolkite university agricultural farm, Guraghe Zone, Ethiopia, to characterize, classify the soils and physical land suitability evaluation for the crop production. Three representative pedons from three slope categories (0-5, 5-10 and 10-15%) were opened and described. Two major crops (maize(zea) and tef(eragrotis) were used for physical land suitability evaluation using simple maximum limitation approach. Thirteen undisturbed and disturbed soil samples were collected from all identified genetic horizon for laboratory physical and chemical soil parameters analysis. The result of study showed that the textural class of the study area entirely clay. The pH of the soils showed acidic to alkaline reaction (pH 5.02- 8.04). The soils were very low in available P (0.9-0.38), high OC% (4.8), very high TN% (1), high K (7.93-9.85(cmolc kg 1soil), medium Mg (2.14-2.31(cmolc kg 1soil). In all pedons the soil was developed from vertic subsurface horizon and is classified as Calcic Vertisols (Hypereutric) according to the World Reference Base for Soil Resources (WRB). Regarding physical land suitability, mapping unit 1Ac was marginally suitable (S3) for maize production due to CEC and pH as limiting factors and not suitable (N) for tef production due to LGP as limiting factor.mapping unit 2Ac was moderately suitable (S2) for maize CEC and pH as limiting factors and not suitable (N) for tef production due to LGP as limiting factor. mapping unit 3Ac was not suitable (N) for maize and tef production due to high pH and LGP as limiting factors. The mapping units could potentially be highly suitable (S1) for maize production if the soil be treated with lime to raise the pH. All mapping units (1Ac, 2Ac and 3Ac) were not suitable for tef production due to long length of growing period being the limiting factor. It is advisable to search crops that suit the climatic (very long maturing crops, >210 days), soil and landscape situation of the study area. cropping, cultivation and fertilization should be implemented so as optimize and sustain the agricultural production.