Seasonal variation in water quality of the Calabar River: Influence of tidal and coastal activities

Abstract

Water quality of the Calabar River Estuary was measured during November, February and May representing the major climatic conditions and during high tide, low tide and mid-tide representing the most important tidally forced hydrodynamic conditions in the estuary. The lowest water quality (<70%) was observed at the bottom levels in May during the wet season. Water quality changes over a cross section transect of the River at Duke Town Harbour did not indicate any significant influence of coastal activities and land use. The homogeneity in water quality is attributed to the high tidal activity. Ionic adsorption/desorption as well as material sedimentation/resuspension induced by tides are the major factors of variability in water quality of the estuary. Any development, which has the potential to modify these processes, may result in large-scale water quality changes with dire consequences on water uses and biological conservation.



Key Words: Water quality, Tidal regimes, Seasonality, Calabar River Estuary, Nigeria.

[Global Jnl Environ Sci Vol.2(2) 2003: 106-111]