Evaluation of Tef [Eragrostistef (Zucc.) Trotter] Genotypes for Acid Soil Tolerance Using Stress Indices

Abstract

Select physico-chemical parameters of Bonny Estuary were investigated in order to gauge the obvious threat of human activities along the estuarine catchments on the estuary. This is crucial because of the diverse human activities of crude oil loadings, indiscriminate refusing dumping, residential housing and unrestricted fishing activities going on in the catchment. Samples were collected and investigated from five sampling stations representing fuel depot site, refuse dump, fishing spots, residential quarters and an upstream station far removed from direct human impacts (control). Water samples were collected for six months representing wet and dry seasons. Samples were analyzed for Nitrate (NO3), Sulphate (SO4), Phosphate (PO4 3-) Dissolved Oxygen (DO), Biochemical Oxygen Demand (BOD) and Turbidity. Result from the investigation reveal that there were significant seasonal differences in measured parameters (p<0.05). There were no significant differences between sample stations (p>0.05). However, station 5 (control) exhibited relatively lower values in almost all measured parameters compared to other stations, suggesting greater ecological stability in the control station. BOD values were inversely correlated to DO values. Values of Nitrate, sulphate, phosphate and turbidly exceeded recommended safe limit. Based on the findings of this work, it can be concluded that Bonny estuary is under mild threat from land based activities.