7. Composition of the Invasive Macrophyte Community in three river basins in the Okyeman Area, Southern Ghana

Abstract

A survey was carried out to study the composition of the invasive aquatic macrophyte community including submerged forms, in three river basins the Okyeman area namely the Ayensu, Birim and Densu basins. Of prime interest was the presence of any one of these four species, Pistia stratiotes (water lettuce), Eichhornia crassipes (water hyacinth), Azolla species (fairy fern) and Salvinia molesta (Kariba weed), a floating water fern, which are alien to Africa. The number of invasive macrophytes encountered in the survey of the macrophytes was low with Eichhornia crassipes (water hyacinth) conspicuously missing. A concerted effort to exclude these species from our freshwater bodies is suggested as the presence of any of these four is regarded as detrimental to aquatic life, because once they become established they tend to prevent the growth of native ones.