Physical, chemical and macrobenthic invertebrate fauna characteristics of swampy water bodies within University of Lagos, Nigeria

Abstract

A comparative study conducted on three swampy water bodies draining through the University of Lagos into the Lagos Lagoon describes the physical, chemical and macrobenthic invertebrate characteristics of these water bodies at the study sites. Three stations, one at each water body were sampled fortnightly from June to December, 2000. Water temperature, total alkalinity and salinity were the only physical and chemical conditions significantly different at the study stations. The physical and chemical conditions at stations A and B were similar and significantly different from station C exposed to domestic effluent, thereby, reflecting the perturbational stress at that site. A total of 43 benthic invertebrate taxa belonging to five classes, 31 families and 2424 individuals were recorded at the study stations. The study stations can be ranked as B > A > C and B > C > A in terms of number of taxa and number of individuals, respectively. The low number of taxa and individuals in stations A and C is suggestive of habitat instability. The pattern of invertebrate distribution and abundance was influenced by the fluctuations in the abundance of Oligochaeta, Hemiptera and Diptera. The taxon richness (D), genera diversity (H) and evenness (E) estimated for the study sites supported the trends observed in the numbers of taxa occurring and their abundance. The low concentrated dominance (C) calculated for station B compared to stations A and C reflects an ecologically heterogenous and relatively stable site. Morisita-Horn index showed that station C was dissimilar to stations A and B. Jaccard's coefficient indicated that all stations were dissimilar. In general, the faunal comparison showed that the level of exposure to urban discharges, inert pollutants and the presence of aquatic macrophytes influenced the differences in the abundance, occurrence and number of taxa at the three stations.

Factors Affecting Macrobenthic Invertebrates Distribution in Badagry Creek, South Western Nigeria

“…The chemistry of aquatic environment generally depends on the physical and geological features of the environment and some of the parameters evaluated in this study is to ascertain that the physical and chemical parameters estimated were within the range of those reported for similar brackish water [22,23,24,25] in Nigeria. Conductivity and total dissolved solids fluctuated during the wet and dry months and the elevated values of these parameters in the months of the dry periods are said to be due to evaporation while the low levels of these parameters observed in the wet months are a reflection of dilution by rainfall As indicated by the CCA ordination, the environmental variables are correlated with significant part of the variations in the individual species abundance.…”

“…Over-time the benthic invertebrates become dominated by resilient communities that can tolerate stressful environmental conditions in the bottom sediment [1]. Once established, these resilient communities usually alter their environment through physical sediment alteration, enhancing sediment-water fluxes, increasing available area for solute exchange by reworking and bioturbation [6][7][8][9] in addition to promoting community succession, species settlement and populations persistence [10][11][12]9,1].…”

Spatio-temporal variations in water and sediment parameters of Abule Agege, Abule Eledu, Ogbe, creeks adjoining Lagos Lagoon, Nigeria

“…The study locations showed limited concentrations of phosphates as compared with that of nitrates. The increase in nutrients of the study sites can be attributed to the increase in anthropogenic activities (Edokpayi and Ayorinde, 2009;Edokpayi et al, 2010). Sept.…”

“…Ogbe creek is non tidal and experience flooding in the wet season as a result of surface runoff (Nwankwo and Akinsoji, 1992). The stream channel width is about 30 m with an average flow velocity of 0.5 cmS -1 (Edokpayi and Ayorinde, 2009). The station has a coordinate of 3°23.527'E and 6°30.627'N.…”

Morphodynamics in a Tropical Shallow Lagoon: Observation and Inferences of Change

“…Lagos' population is currently about 17 million, up from 2 to 3 million in the 1970s. Despite this pressure, research to date on the lagoon only identifies ecological studies [17][18][19], lagoon sensitivity and pollution studies [17,20,21], fishery and plankton sustainability [22,23] and partial pressures on the lagoon ecosystem habitat. All these, although, are part of the outcome of the impact created by the growing population (about 17 million) of the city of Lagos Nigeria around the Lagos Lagoon.…”