Assessment of Periphyton Biomass and Water Quality by Chlorophyll Determination of Ifewara reservoir, Osun State, Nigeria
Publication Date: 10/07/2020
Author(s): Ogunmola O.P., Adeniyi I.F., Adesakin T.A., Aduwo A.I., Daisi O., Akinpelu O., Aanuoluwa I..
Volume/Issue: Volume 3 , Issue 4 (2020)
Abstract:
This study explored the use of taxonomic composition of periphyton and chlorophyll to assess the Ifewara reservoir status. Glass slide was attached to wooden slab and submerge in water between 2 to 5days then removed from water and periphyton samples were scraped from glass slides with a spatula. The scraping was emptied into a sterilized plastic vial containing 20 ml of Lugol’s solution for preservation. 2.0-5.0 liter of surface water-sample is often convenient for measurement of Chlorophyll in the biomass from established stations (inflow, middle and lower lentic basin). The recorded periphyton was microphotographed, counted and identified using various keys and guides. A total number of ninety (90) species of periphyton was recorded belonging to phytoplankton (73) and zooplankton (170 species. Spatially, bacillariophyta (124±52 Org/m3) recorded the highest mean abundance at the upper basin station. Chrysophyta (1.0±0.6 Org/m3) was higher at middle basin station and highest mean abundance for chlorophyta (30±12 Org/m3), chlorophyll a, b and c (3.14±0.39 Org/m3, 2.10±0.46 Org/m3 2.37±0.41 Org/m3) was observed in lower basin station. Temporally, bacillariophyta, cyanophyta, euglenophyta and copepod, cladocera, rotifer, chlorophyll a, b and c recorded the highest mean abundance during the dry season while chlorophyta and chrysophyta were dominant in the rainy season. Chlorophyta were the predominant group and account for 50.68% of total species composition followed by bacillariophyta (32.88%) and least was chrysophyta (1.36%). Among the periphyton fauna, rotifer was dominant with 76.47% and followed by protozoa (11.76%). The study revealed that reservoir is composed of highly diversified periphyton groups with great potential to support aquatic community and fishery production and portray the reservoir as unpolluted, dilute fresh water suitable for its intended primary purpose of water supply to the riparian communities.
