Effect of cement production on vegetation in a part of southwestern Nigeria
The impact of cement dust emissions from the factory of West African Portland Cement at Ewekoro in Southwestern Nigeria on the surrounding vegetation was investigated. Sample plots of 20 m x 20 m were established at 1 km intervals from the factory site up to a distance of 10 km intervals from the factory site up to a distance of 10 km in the four cardinal directions. Leaves of common species were randomly selected for chlorophyll content analysis, leaf abundance and leaf area measurement. Woody as well as herbaceous species encountered within the established plots were enumerated, while soil samples (at 0-15 cm) were collected for laboratory analysis. It was found that chlorophyll contents, leaf abundance, leaf area, woody species density and basal area increased significantly with increasing distance from the factory site. Organic matter, total nitrogen, pH and moisture contents of the top soil did not vary significantly across the study site. Available phosphorus decreased in concentration with increasing distance from the factory site. On the whole, cement dust deposition affected the vegetation parameters studied, up to a distance of 5 km from the factory site.