Some limnological studies of an aquatic habitat used for fishing and irrigation in Ngala, Borno State, Nigeria

The limnological characteristics of the aquatic habitat were studied with special emphasis on water temperature, calcium hardness and chlorine levels as they affect the abundance of Bulinus globosus and Bulinus forskali on one hand and their interfactorial effects on the other. The single regression analysis showed that calcium hardness was the only factor that showed direct significant (P<0.05) positive effect on abundance of B. globosus and B. forskali. Similarly, water temperature was significantly (P<0.05) negatively correlated with chlorine and calcium hardness levels. Water temperature levels were negatively correlated with the abundance of both snail species. The behavioural patterns of the fishermen exposed them to the risk of infection with schistosomiasis.