AGRO-ECOLOGICAL ASSESSMENT OF PHYSICO-CHEMICAL PROPERTIES OF SOIL IN KULFO WATERSHED, SOUTH WESTERN ETHIOPIA

Abstract

The great variation in physical landscape of the Ethiopian highlands gives rise to the formation of different relief features, which are inurn causes for variations in agro-climatic and soil parent materials of the country. The aim of the research was to characterize the physio-chemical properties of soils in Kulfo Watershed, Southwest Ethiopia. In the study both primary and secondary data were used. The primary data was generated from Kebele transect walks, composite soil sample and Soil GPS points of varying land use/ cover types, while secondary data was obtained from satellite imaginaries, National Metrological agency and Central Statistical Agency etc. 36 composite surface soil samples (0-30cm depth) were collected from varying land use/ cover types of three agro-ecologies of the watershed namely, upland, mid and lowlands. Collected soil data Were analyzed in soil laboratory of Arba Minch University. The study result revealed that Kulfo watershed was characterized into four traditional agro ecologies, namely lowland (20.9%), midland (35.9 %), highland (37.4%) and cold high mountain areas (5.8%). The soil analysis results showed that dominantly soils of the watershed are characterized as texturally clay loam to sandy loam and they have no significant textural class difference among soils in all agro-ecologies. The soil reaction varies from moderately acidic (with pH 5.4) to neutral (pH 7.3) status.Grid based climate analysis showed that precipitation and temperature pattern showed gradual decrease from northern to the southern parts of the watershed.Furthermore, the analysis showed that soil chemical properties in the watershed are dominated by medium organic matter, low total nitrogen, very low available phosphorus (3.83-6.65ppm), high potassium and very low to low CEC content. Therefore, in order to rehabilitate theproductivity of soil-chemical properties the application of Soil and Water Conservation measures in the upland, use of organic manure in the low lying areas could be the viable options for promising crop yield in the area Keywords: GIS and Remote Sensing Techniques, physio-chemical properties, transect walk, Agro ecology, Kulfo Watershed.