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Aquatic Insects Diversity and Water Quality Assessment of a Tropical Freshwater Pond in Benin City, Nigeria
KOMOLAFE, BO & IMOOBE, TOT
Abstract
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’s 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.
Keywords
Aquatic insects; bioindicators; biodiversity; water quality; pond
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