Margaret F . A . Akwetey

This paper investigates the hydrographic characteristics of the Kakum and Nyan estuaries located on the southwestern coast of Ghana in order to gather baseline information for subsequent monitoring. Surface and bottom measurements of temperature, salinity, dissolved oxygen (DO), pH and turbidity were taken using a water quality checker (TOADK - 22 A) at various sampling stations from August 2011 to July 2012 during low tides. Depth was also measured. During the "peak" dry and wet seasons (February and July respectively), measurements were taken at high and low tides and the extent of saltwater penetration into the estuaries was determined. Temperature and DO were generally similar in both estuaries, but turbidity and pH were higher in Nyan estuary than Kakum estuary for some months. Salinity was higher at the mouths than the other stations. Both estuaries showed characteristics of positive estuaries with higher bottom salinities than surface ones at most stations except th...

This paper on benthic macroinvertebrates of Kakum and Nyan estuaries is meant as baseline information in the wake of offshore oil drilling, mining and land use due to growing human population on the southwestern coast of Ghana. Ekman grab (0.0225 m2) was used to sample benthic macroinvertebrates monthly from August 2011 to July 2012. Crustacea (58.96%) and Annelida (35.23%) dominated the 40 species encountered in the Kakum estuary while Annelida (88.15%) alone dominated the 45 species found in the Nyan estuary. The annelids Nereissp., Capitella capitata and Cossura sp. and the dipteran Chironomus sp.were the main pollution tolerant species recorded while the annelids Scoloplos sp. and Amphiglenasp. were the known pollution sensitive ones found. An unknown amphithoid (Amphithoid 'A') andaGammarussp. dominated the Kakum estuary community with mean densities ranging between 67.27 ± 30.94 ind./m2 to 535.49 ± 275.50 ind./m2 and 26.91 ± 10.71 ind./m2 to 398.25 ± 143.90 ind./m2resp...

In order to enhance ecological knowledge for coastal and mangrove ecosystem conservation in Ghana, the study documents the taxonomic groups of benthic macrofauna and fish assemblages in an urban mangrove swamp as its fundamental objective with emphasis on their composition, richness and diversity. This is because benthic and fish fauna of mangrove habitats are amongst the least studied biota in Ghana. Fish and benthos sampling was undertaken from five randomly selected pools within a mangrove stand during the wet and dry seasons using pole-seine net (7 m long and 1.5 m depth, with stretched mesh size of 5 mm) and an Ekman grab (15 cm × 15 cm dimensions), respectively. All samples were preserved in 10% formalin for laboratory analysis. The results indicated a more diverse macrozoobenthic community in the wet (H¹ = 1.8) than dry season (H¹ = 1.5) . Overall, five out of a total of 13 genera found are intolerant to pollution and four moderately tolerant, while four comprising polychaete...