Seasonal variation of the hydro-environmental factors and phytoplankton community around waters in Tincan Island, Lagos State, Nigeria

Abstract

The phytoplankton diversity, pigment, abundance and distribution in relation to physico-chemical parameters were studied from four stations for a period of five months (May – September 2018) and were analysed using standard procedures. Rainfall was highest (329.5 mm) in September and lowest (142.7 mm) in July. The total suspended solid (TSS) had a mean value of 63.10±12.81 mg/L and the total dissolved solids (TDS) had the highest value of 15189 mg/L in May which was not significantly different around the sampling points {P > 0.05}. The pH and nitrate level recorded had a mean value of 7.25±0.33 and 3.11±1.33 mg/L respectively. Microscopic identification revealed a total of 129 species belonging to 62 genera, 22 families and five divisions in the following order of specie abundance: Bacillariophyceae (65 taxa) > Cyanophyceae (27 taxa) > Chlorophyta (20 taxa) > Dinophyceae (10 taxa) > Euglenophyceae (7 taxa). The high dominance of Microcystis aeruginosa observed was indicative of organic pollution. The range of community structure indices were as follows: Margalef Index (0.1406 – 5.295) and Shannon – Weiner Index (0.02644 - 0.4979). The relatively high nutrient status favours the high abundance of phytoplankton which is understood to be deleterious to the ecosystem. Municipal wastes must be treated or recycled before discharge and a continuous environmental surveillance is required to maintain the biological integrity of this area.
 Keywords: Phytoplankton, Physicochemical Parameters, Nutrient Status and Tincan Island

Phytoplankton community of the Isaka-Bundu waterway in Rivers State, Nigeria; A polluted tidal mangrove wetland

“…The study showed spatial variations in phytoplankton abundance, where the relative abundance of the phytoplankton families recorded varied greatly, with more species in the control. This agrees with studies by [38] who reported a similar trend. While the low abundance of species in stations 1, 2, and 3 as compared to the control could be likened to the collapse of the phytoplankton community [34]; [39].…”

“…The reasons for such elevation in biomass are more solar irradiation and increased water retention time [33] and more directly, efficient utilization of light and nutrients, and reduced algal wash-out [35]. The higher species diversity and richness in the control as revealed by the Shannon-Wiener and Margalef's indices respectively were due to higher species composition observed in the station during the period of study while the lower Shannon-Wiener diversity and Margalef's indices in the other stations could be associated with lower salinity and temperature as reported by [38]. This observed decrease in the species diversity and richness could also be attributed to changes in environmental variables due to pollution resulting from industrial effluent discharge into the river.…”

Assessment of Interstitial and Surface Water Quality of Ibaka Creek Rivers State, Nigeria: The Case of Artisanal Refinery Activities

“…The higher pH in interstitial water can be influenced by factors such as biological activity, decomposition of organic matter, and buffering capacity of sediments [22]. The higher pH in interstitial water also suggests a more alkaline condition, which could be influenced by the presence of alkaline substances [51]. The lower pH in surface water may be due to acidic inputs from atmospheric deposition or organic matter decomposition [24].…”

Minerals and Trace Elements Content of Selected Shellfish from Opuro-ama Waterfront: An Impacted Tidal Creek in Rivers State, Nigeria

“…The pH could also be influenced by the acidity of the bottom sediment and biological activities in the sediment [22]. The variation in the high density of leaf-littered around the sediment and the subsequent decay could have contributed to the slightly acidic nature of the interstitial water from the creek [25]. The pH range of the interstitial water also falls within the optimum range of most aquatic organisms which are 6.5-8.5°C, 6-9°C, and 6.5-8.5°C respectively, and will support rich primary productivity, shrimp and fish production as reported by [20,21,26].…”