Year: 2025
Type: article
Abstract: The objective of this paper was to assess the effect of agricultural runoff on the aquatic health of River Ethiope, Delta State, Nigeria, by integrating physicochemical, nutrient, heavy metal, and biological analyses with socio-economic surveys using appropriate standard procedures with Questionnaire surveys of 120 respondents complemented environmental monitoring. Results revealed significant spatial variation, with the middle course (S2), adjacent to intensive farmlands, exhibiting the most degraded conditions. Nitrate (6.12 mg/L) and phosphate (1.84 mg/L) peaked at S2, coinciding with lowest DO (5.53 mg/L). Pb (0.031 mg/L water; 22.8 mg/kg sediment) and Cd (0.009 mg/L water; 3.4 mg/kg sediment) were elevated, with sediment Pb exceeding sediment quality guidelines. Macroinvertebrate diversity declined at S2 (H′ = 1.82), dominated by pollution tolerant Chironomidae, while sensitive taxa were scarce. Community perceptions aligned with scientific findings: 80% observed increased turbidity, 67% reported fish scarcity, and 70% farmed within 10 m of the riverbank, though only 35% recognized agriculture as a pollution source. Correlation analysis confirmed strong linkages between agricultural land use, nutrient enrichment, heavy metal contamination, and biodiversity loss. The study concludes that agricultural runoff is a major driver of water quality deterioration and ecological decline in River Ethiope and provides the first integrated ecological and socio-economic assessment of runoff impacts on River Ethiope, offering evidence-based insights for sustainable watershed management in the Niger Delta.
Institutions: Delta State University, Southern Delta University, Ozoro
Language: English
Subfield: Water Science and Technology
Field: Environmental Science
Domain: Physical Sciences
Open Access status: diamond
OpenAlex ID: W4416593501