Abstract:
This research was aimed at investigate the soil depth effect on selected soil physico-chemical properties and farm management under mango plantation: in the case of Ukke Kebele, Angar Gute District, East Wollega, Oromia, Ethiopia. Purposive sampling technique was used to execute the household survey and to obtain soil samples, the farm land was stratified by Zigzag (Z) manner and totally 3 composite soil samples were collected from cultivated land at depth of 0-15, 15-30 and 30-45 cm were taken to Ambo University Laboratory for analysis. The variation in available phosphorous, soil pH, and clay were significant at (p < 0.05) with soil depth. Bulk density, total porosity and cation exchange capacity have positive relationship and highly significant at p ≤ 0.001 with soil depth. The organic carbon, organic matter, electrical conductivity and total nitrogen were insignificant (p >0.05) and negative relationship with soil depth. The bulk density of the soils under the different depths was ranged from 0.97 and 1.07 g cm-3 and the total porosity was ranged from 55% to 59%, which shows that there is less soil compaction in the study area. The higher (9.60) and the lower (9.86) values of soil pH were observed in depth of cultivated land, which indicated that there was soil acidity in study area. The higher (0.032 ds/m) and lower (0.03ds/m) values of electrical conductivity were found in the cultivated land. The mean values of organic matter were ranged 1.075 to 1.015 of cultivated land. However, the total nitrogen ranged from 0.0581 to 0.0157% with mean value 0.036. The value of available phosphorous was ranged from 17 to 15.5 ppm, which implies that there is optimum level of available phosphorous in the study area. All the exchangeable basic cations values were within low to high ranges in tree soil depths. The values of cation exchange capacity were also ranged from 33 to 33.3% rate in a soil depth, which showed there was high soil capability of nutrient reservoir and low leaching. Therefore, the adverse effect of soil depth on selected physico-chemical properties was the remarkable problems and also the proper farm management practice is essential in the study area to enhance crop productivity and sustainable utilization of soil resources
