Effects of the Volta dam on the properties of two soil series in the Lower Volta floodplain in Ghana

Abstract

Since the completion of the Volta dam, seasonal floodings of the Lower Volta floodplain have ceased, resulting in a drastic change in the soil environment. Post-dam modal profiles of Amo and Tefle series, in the floodplain, were analyzed and compared with the available pre-dam data. The objectives were to identify changes in the soil properties, and to classify the soils according to the USDA and FAO systems. The data showed that the pH of Amo series decreased from about 6.0 to 4.9 within the 0 - 100 cm depth; its exchangeable acidity, however, increased by 1.0 to 5.0 cmol (+)/kg. Organic matter content in the surface horizons of Tefle series decreased from 60 to 31 g/kg, and its structure improved from massive to blocky. These changes were caused mainly by the change in the moisture regimens of the soils. By the USDA Taxonomy, the Amo and Tefle series are Vertic Dystropept and Alic Dystraquert, respectively.


Ghana Jnl agric. Sci. Vol.30(2) 1997:
171-179