Chemistry and Materials Research www.iiste.org ISSN 2224- 3224 (Print) ISSN 2225- 0956 (Online) Vol.8 No.7, 2016 64 Physico-Chemical Properties and Agricultural Potentials of Soils of Tembaro Woreda, Kembata Tembaro Zone, Southern Ethiopia Tadele Buraka 1 Alemu Lelago 2 1.Department of plant science, Wachemo University, P O Box 138, Durame, Ethiopia 2.Department of Chemistry, Wolaita Sodo University, P O Box 138, Wolaita Sodo, Ethiopia Abstract Physico-chemical properties of soils of a particular area is crucial for determination of its potential and constraints based on which appropriate management interventions could be applied for enhanced and sustained agricultural production and productivity. Therefore, the objectives of this study were to determine physico-chemical properties of the soils of Ambukuna microcachment and to identify its potentials and constraints for crop production. Five sites representing a soil each were opened and profile in each site was described for its morphological, physical and chemical characteristics according to standard procedures. A total of 20 disturbed soil samples and 16 core ring samples were collected from five representative sites. The samples were analyzed in the laboratory for texture, BD, FC, PWP, Soil pH, EC, OC, TN, av.P, av.K, exchangeable bases and CEC. The results of the study showed that the proportions of soil separates varied among sites. The BD varied from 1.13 in the surface site 1 to 1.26 gcm -3 in the site 3. Soil pH ranged from 5.4-6.8 in the surface of all sites with further decrease with depth indicating that the soils in the watershed are strongly acidic to slightly acidic. The OM and TN contents ranged from 2.96- 5.95 and 0.26-0.45% in the surface soil and they were in the low, low to medium and high categories, respectively. Available P was below critical values for all sites except for sites 1 and 4. Exchangeable K was above critical value in all sites. Exchangeable Mg varied from 2.87 in surface soils of site 3 to 3.98 cmolc kg -1 in the surface soils of site 4. The observation with exchangeable K and Mg implies that there is leaching phenomenon in the study area. Ca ranged from 5. 37 cmolc kg -1 in site 5 to 16.80 cmolc kg -1 in site 2. The CEC from 19.22 cmolc kg -1 soil in surface of site 5 to 36.43 cmolc kg -1 soil in the surface soil site 1 indicating they are in the medium to high ranges. Most of the soil physical and some of the chemical characteristics studied could be ranked as good indicating that the area has high potential for agricultural production. However, acidic soil reaction observed in the study area should attract attention for its management now and in the future. P is also found to be the most important limiting nutrient for crop production in the area. Thus, management of P is indispensible for enhanced agricultural production in the area. Maintenance and enhancement of organic matter content of the soil in the watershed is also recommended for improving soil quality and sustainability. Keywords: Morphological Characteristics, exchangeable bases, total nitrogen INTRODUCTION The overall productivity and sustainability of a given agricultural sector are functions of fertile soils and productive lands. However, soil fertility depletion is the fundamental biophysical cause for declining per capita food production in sub- Saharan African countries in general (Sanchez et al., 1997, Sanginga and Woomer, 2009). The study and understanding of soil properties and their distribution over an area has proved to be useful for the development of soil management plan for efficient utilization of limited land resources. Moreover, it is very important for agrotechnology transfer (Buol et al., 2003). Ethiopian agriculture accounted for 41.6% of GDP, 83% of export earrings and 90% of total employment (MoFED, 2014). As a result, agriculture remains to be Ethiopian economy’s most important sector. Ethiopia has great agricultural potential because of its vast areas of fertile land, diverse climate, generally adequate rainfall, and large labour pool (CSA, 2008). The country has a total surface area of 111.8 million ha (Mabbutt, 1984); of which 62.81million ha are estimated agriculturally productive (Mishra et al., 2004). However, Ethiopia’s agriculture is characterized by low production per unit area and the sector is dominated by about 11.7 million smallholders responsible for about 95 percent of the national agricultural production while large farms contribute only 5 percent of the total production (MoA, 2011). This shows that the overall economy of the country and the food security of the majority of the population depend on small-scale agriculture. Although the country has enormous potential for agricultural production (such as in terms of land, climate and water resources), it is not uncommon facing a serious and chronic problem of food crop shortage in the country (Yohannes, 1989). Ethiopia with its immense potential soil resource base suffers from food insecurity (Mishra et al., 2004). This is a paradox, which invites researchers to investigate the causes of the problem and suggest feasible solutions. As Ethiopia is an agricultural country, its development is strongly linked with the agricultural resource base. The soil as one component is the basic resource that provides opportunities and constraints for agricultural development. Therefore, knowledge about the soils of the country is important for technology transfer, decision making and planning and policy formulation. However, the soil information currently available is very limited and