PALAEOECOLOGICAL STUDIES OF TWO LENTIC ECOSYSTEMS IN AKWA IBOM STATE, SOUTHERN-NIGERIA

Abstract

This study aimed to conduct palaeoecological investigations on two aquatic ecosystems, Ikot-Akpa Erong (Lake) and Akpa Utong (Pond) within Ibesikpo Asutan Area in Akwa Ibom State. The primary objectives were to assess past and present-day pollen flora in the study area, evaluate factors influencing pollen deposition, characterize the pollen, and establish a baseline pollen calendar. The study locations were selected based on their ecological significance and distinct environmental features. Soil samples collected from depths of 15 cm and 30 cm were subjected to acetolysis for pollen morphology assessment. Microscopic analysis revealed a diverse palynomorph assemblage, including Gliomastix spp., Striatotricolporites spp., Encephalartos spp., Verrucatosporites usmensis, Annoria spp., Symphonia spp., and others, totaling 45 selected pollen types. Notably, Gliomastix spp. dominated across both sites, contributing to a significant portion of the pollen assemblage. The physicochemical analysis of sediments exhibited variations in parameters such as pH (8.475), temperature (30.05°C), total dissolved solids (41 mg/L), electrical conductivity (65.2 ds/m), and particle size distribution (% Sand: 9%, % Silt: 21.15%, % Clay: 69.85%). The observed dominance of Gliomastix spp. may be attributed to its adaptive advantages in response to specific environmental conditions. In conclusion, this study provides valuable insights into the paleoecology of the selected aquatic ecosystems, highlighting the dominance of Gliomastix spp. as a noteworthy feature. Further investigations on the ecological roles of Gliomastix spp. and continuous monitoring of these ecosystems for comprehensive environmental management strategies is recommended