Physical and Chemical Characteristics of Dustfall in the Lower Benue Valley Nigeria

Abstract

The increasing amount and duration of dustfall in the Lower Benue valley (Lat. 7.25°N – 8.25°N and long. 8.00°E – 8.50°E) has become an important environmental issue in recent times. Most disturbing is the fact that the characteristics of the dust
are not known; as such its effects on the soil (the ultimate recipient) cannot be assessed. This study was carried out to quantify dustfall, investigate its physical and chemical characteristics and its effects on the soils over which it settles. The study involved the collection of both dust and soil samples in 3 locations in the Lower Benue Valley for 3 consecutive dusts seasons. They were analysed for texture, pH, organic carbon, total N, extractable P, CEC and exchangeable bases. The study revealed that about 300-320 kg of dust/ha was deposited yearly in the area. Of this amount, fine silt accounted for 49%
followed by clay (30%). The dust had higher contents of organic carbon, total N, extractable P, and total exchangeable bases than native soils. Cation exchange capacity and pH values were also higher in the dust than in the native soils. The differential quantitative compositions of the dust and the native soils suggest that the dust could influence soil properties.

Keywords: Physical and Chemical characteristics, dustfall, lower Benue Valley

Nigerian Journal of Soil and Environmental Research Vol. 7 2007: pp.7-14