ASSESSMENT OF SOIL PHYSICO-CHEMICAL PROPERTIES OF SHONGA IRRIGATION SCHEME FOR IRRIGATED AGRICULTURE

Abstract

Continuous agricultural practices have impacts on soil properties and these impacts may be negative on soil, crop and groundwater quality. This could be as a result of the quality of water used, method of application and the nature of the soil viz the physical and chemical composition of the soil. The physical and chemical characteristics of soil at Shonga irrigation scheme were evaluated to assess the fertility and productivity status of the soils. Five soil samples were collected from different locations at soil depth of 30cm in the study area using soil auger. A random sampling method was used to sample soil and the soil samples were taken to the laboratory for chemical and physical analysis. Physical analysis results showed that the soil of the study area was sandy loam; the available soil moisture contents obtained is low for 0-10cm, 10-20cm and 20-30cm crop rooting depths. The low percent of soil moisture ranged from 1.05 to 1.12%. The particle density, soil bulk density and porosity were 2.63g/cm3, 1.62 g/ cm3 and 38.4% respectively. Chemical analysis results revealed that the value of soil pH lies in the alkaline side and it ranged from 7.80 to 8.81. The organic carbon ranges from 0.52to 0.72% of the entire soil nutrients relating to soil fertility and is available in medium proportion of organi carbon. Electrical Conductivity (EC) values ranges from 0.50 to 0.73dSm−1 and all the soil samples have lower EC values. Available potassium content ranges from 125.31 to 630.15kg/ha with the majority of the soil samples in the study show high available potassium. Nitrogen which is an essential plant nutrient for growth of plant canopy is low in all soil samples. The available phosphorous content of the soil is high which ranged from 15.11to 54.13kg/ha Therefore, it is essential to give attention to proper monitoring of the soil condition of the farm land in order to prevent soil deterioration. It was recommended that For efficient production output, manure or compost should be applied in appropriate proportion to stabilize and correct nutrient deficiency in the soil, periodical test has to be conducted to ascertain any changes in values obtained and careful selection of crop and management alternatives is required if full yield potential is to be achieved.