Pedological investigation of soil quality indicators in Tapioca growing soils

Manihot esculenta, the most important tropical root crop which supply dietary staple food for about 800 million populations worldwide. Twenty soil profiles that represent the soil Pedology and soil quality are similar in their concept in relation to soil formation. In this regards, soil quality can be considered as part of the science of pedology. Significant differences in yield of Tapioca (Manihot esculenta) with selected soil properties and subsequent interpretations as influenced by land use are explained.

Soil samples were taken from designated pedogenic horizons for physico-chemical properties in the laboratory. Soil textural class, saturated hydraulic conductivity, Cation Exchange Capacity, Base Saturation Percentage, soil organic carbon, exchangeable cations, available N, P, K content and available micronutrients were analysed. The general fertility of the soils in the area is discussed highlighting their potentials and constraints.

A comprehensive analysis of soils in the study area showed that shallow soil depth of <47 cm and more clay of 44% with high bulk density of 1.4 gcc^-1, low hydraulic conductivity of 0.12 cmhr^-1, low base saturation percentage of 77%, more exchangeable sodium percentage of 7.96% with low available N, P and K of 110, 10.75 and 142.25 kg ha^-1, respectively in low yielding soils are the major constraints in the tract might behind the yield differences in Cassava.