Increasing human activities in coastal areas of Ghana have led to the degradation of many surface
waterbodies, with significant consequences for the ecosystems in the affected areas. Thus, this
degradation extremely affects the health of ecosystems and disrupts the essential services they
provide. The present study explored the use of benthic macroinvertebrates as an indicator of
estuarine degradation along the coast of Ghana. Water and sediment samples were collected
bimonthly from Ankobra, Kakum and Volta estuaries for physicochemical parameters, nutrients
and benthic macroinvertebrates. The findings revealed the dominance of pollution-tolerant taxa
such as Capitella sp., Nereis sp., Heteromastus sp., Tubifex sp., Cossura sp. and Chironomous sp. in
Kakum Estuary while pollution-sensitive taxa such as Scoloplos sp., Euridice sp., Lumbriconereis sp.
and Pachymelania sp. in the Volta Estuary. The species-environment interactions showed dissolved
oxygen, temperature, salinity, orthophosphate, nitrates, ammonium, electrical conductivity,
turbidity, and chemical oxygen demand as the most significant parameters that
complement the use of benthic macroinvertebrates as indicators of environmental quality in the
studied estuaries. There were correlations of some benthic macroinvertebrate taxa with environmental
factors in the estuaries suggesting low, moderate and high levels of pollution in the
Volta, Kakum and Ankobra estuaries, respectively. Nevertheless, the study finds Kakum Estuary to
be the ecologically healthiest estuary than the Volta and Ankobra Estuaries. Therefore, the study
has shown benthic macroinvertebrates as a key indicator of ecosystem health alterations, and it is
recommended that they should be incorporated with other environmental data for pollution
monitoring in Ghanaian coastal waters. |
University of Cape Coast