10 research outputs found
Assessment of Zooplankton Community Structure of the Bahir Dar Gulf of Lake Tana, Ethiopia
The zooplankton composition of the Bahir Dar gulf of Lake Tana was studied in June and July, 2007. A total of forty four zooplankton species made up of 16 species of rotifers, 16 species of cladocerans and 12 species of copepods and their developing stages were recorded in the following order of dominance; Rotifera > Cladocera > Cylopoida > Calanoida. The number of species was not too different among the three sampling
Stations, however, average zooplankton abundance, was significantly higher (
Assessment of the Impact of Effluent from a Soft Drink Processing Factory on the Physico-Chemical Parameters of Eruvbi Stream Benin City, Nigeria
An investigation of the impact of industrial effluent discharged into Eruvbi stream was carried out in the wet season months of March to August, 2009. Water samples from three selected points in the stream were analysed for temperature, total dissolved solids, turbidity, pH, electrical conductivity, dissolved oxygen, biochemical oxygen demand (BOD5), total alkalinity, chloride, hardness, calcium, magnesium and nitrate. Samples were collected at three sites, designated as station 1 (upstream of effluent discharge point), station 2 (effluent discharge point) and station 3 (downstream of effluent discharge point). Water temperature, turbidity, alkalinity, hardness, calcium and magnesium were found to be significantly higher at the discharge point (Station 2). The parameters when compared with Federal Environmental Protection Agency (FEPA) limit for discharge into Nigeria surface waters and WHO guidelines, turbidity in stations 2 and 3 were found to exceed the maximum allowable limit (5NTU) while dissolved oxygen level at all stations were lower than the minimum allowable limit (5mg/L) for aquatic life. All other physiochemical parameters including biochemical oxygen demand were below the recommended limits in all stations. This physico-chemical regime is an indication of the deteriorating water quality of the stream at the discharge point and downstream due to the effluent inflow.
Keywords: Benin City, Industrial effluent, Physicochemical, Stream, Water qualit
Aquatic Insects Diversity and Water Quality Assessment of a Tropical Freshwater Pond in Benin City, Nigeria
Aquatic insects are species of significant importance to water bodies
because they serve various purposes including nutrient cycling, vectors
of pathogens and bioindicators of water quality. Analyzing their
community structure is a veritable tool in studies of biodiversity and
quality of limnetic ecosystems. Therefore, we investigated the health
status of a pond in Benin City, Nigeria using insect\u2019s abundance,
composition, distribution and physicochemical parameters of the
waterbody. Insects were sampled using sweep nets and identified to the
species level while water samples were collected and analyzed using
in-situ and ex-situ methods to determine the physicochemical properties
in three sampling stations. The results of the physicochemical
assessment of the water indicated that conditions did not differ widely
between sites (P > 0.05) except for total alkalinity, and the
recorded values were well within the ambient FMEnv permissible limits
for surface water except for dissolved oxygen, turbidity and phosphate.
A total of 10 insect taxa, comprising of 103 individuals in 2 orders
were recorded in the study and among the orders, Hemiptera comprised of
7 species and Coleoptera comprised of 3 species. Majority of the insect
fauna found in this study are typically found in similar water bodies
in the tropics. However, the obsereved insect community structure
revealed a relatively low taxa richness with a dominance of
pollution-resistant species which suggests a moderately polluted
condition of the waterbody