Effects of Industrial Effluents on Catfish Ecosystem In Ilorin Metropolis, Nigeria

Abstract

The ecological balance of aquatic ecosystems, particularly those supporting vital species like catfish, is increasingly threatened by industrial effluents. This study assessed the toxicological effects of industrial effluents on the catfish ecosystem in Ilorin metropolis. The objectives were to determine the physico-chemical properties of water from a natural fish pond on industrial land-use; compare the physicochemical properties of the water with the standards of WHO and FEPA; examine the growth indicator of catfish in the study area; and assess the relationship between the physico-chemical properties of the water and the growth of the catfish in the study area. Primary and secondary data were gathered and the sampling involved taking 1% of catfish from three natural ponds on industrial land, each with earthen ponds of 50 by 70 meters with a capacity of up to 5000. Water samples were collected from the river and the natural fish pond over a six-week period, divided into three phases corresponding to different developmental stages of the fish. These water and fish samples were subjected to laboratory analysis. Descriptive and inferential methods used in the study were percentages, graphs, charts, the chi-squared test, and a correlation matrix for data analysis. This study revealed that industrial effluents raised the level of parameters such as iron, copper, lead, and electrical conductivity in the water sampled beyond the recommended levels of WHO and FEPA Standard’s guidelines, with mean values of 7.843, 0.23, 1.01, and 260.667 mg/l, respectively. Chemical parameters such as Fe, Mn, Cu, Co, Pb, and I in the water had no significant effect on fish growth as their p-values (0.472, 0.493, 0.180, 0.672, 0.328, and 0.511, respectively) were higher than the 0.05 level of significance. The physical parameters such as pH (0.918), temperature (0.367), nitrate level (0.292), total solids (0.495), and total soluble solids (0.502) did not show any impact on the growth of catfish. The study concluded that fish growth is affected by the availability of zinc in the fish pond, the increase in electrical conductivity, dissolved oxygen, and total dissolved solids in the water. It is recommended that water quality monitoring be conducted to ensure the good functioning of the aquatic ecosystem for increased fish productivity.