Dissecting the urban footprint of unplanned settlements shaping macroinvertebrate communities in Wuye River, Abuja, Nigeria.

Urbanization poses a significant threat to river ecosystems, causing widespread degradation of river health. This study investigates the devastating effects of urbanization on river health, with a focus on the Wuye River in Abuja, Nigeria, and dissects the urban footprint of unplanned settlements on macroinvertebrate communities. Over a six-month period (January-June 2021), we conducted a comprehensive analysis of physicochemical characteristics and macroinvertebrates at four stations, shedding light on the far-reaching consequences of unplanned urban settlements on river ecosystems. The results revealed significant deviations from optimal water quality parameters with reference to WHO guidelines. Station 3, located in unplanned urban settlement, exhibited elevated nitrate concentrations (13.0 mg/L) and heightened turbidity levels (23.6 NTU), indicating compromised water quality. Station 2, located in planned urban settlements, displayed lower nitrate values and turbidity levels. pH values ranged from 7.4 to 7.7 across all stations, suggesting minimal impact on river acidity. Canonical Correspondence Analysis (CCA) showed strong relationships between species abundance and environmental variables. Axis 2 was associated with Naucoris sp., Velia caprai, Chironomus transvalensis, and Cricotopus sp., and was influenced by dissolved oxygen, sulphate, phosphate, nitrate, and turbidity. Axis 1 was linked to seasonally influenced factors, including temperature and electrical conductivity. CCA indicated that Stations 1 and 2 had higher pH concentrations, favouring species like Melanoides tuberculatus, Appasus sp., Neritina lubricate, Bugilies sp. and Bulinus globosus. The findings highlight urgent need for effective management and conservation strategies in water treatment, urban planning and conservation policies to mitigate urbanization's impacts on river health.