Assessment of physicochemical parameters and algal species abundance in selected hand - dug wells water in Nasarawa Local Government area, Kano State

Abstract

Hand-dug wells are natural, inexpensive solution to widespread water scarcity; however, they could be contaminated with toxic algae. This study aimed to assess the physicochemical parameters and survey algal species in water from three hand-dug wells in Nassarawa Local Government area of Kano State (11⁰57'53''N; 8⁰30'50''E). Water samples were collected during May and June 2021. Temperature, pH, Total Dissolved Solids (TDS), Electrical Conductivity (EC), Biological Oxygen Demand (BOD) Dissolved oxygen (DO), Turbidity (TBDT), Nitrate and Phosphate were determined according to (APHA, 2005). Algal composition (org/L) and identification were by using the guide of Palmer (1980). Analyses of variance was used to determine significant differences between means at (p<0.05). All parameters were within permissible limits of WHO. Site B (lined with rocks) had the highest mean values of TDS (513.67mg/L), EC (596.70mg/L) and TBDT (4.60mg/L). Mean values for DO and BOD showed significant differences between sites. A total of 430 org/L algae were identified belonging to 13 genera consisting of Cyanophyta (51.1%), Chlorophyta (16.2%) and Bacillariophyta (32.7%). Site A (the oldest and unlined) was the most diverse. Site C (lined with concrete) had the highest total number of organisms (42.3%). Oscillatoria sp., Navicula sp., Phormidium sp and Dictyosphaerium sp. occurred in all sites. Nitszchia, Gomphonema and Fragillaria were the least abundant. Hand-dug wells should be protected and conserved to ensure a sustainable supply of water for various purposes.