The Bioscientist (Apr 2017)
physico-chemical parameters associated with mosquito abundance in rice farms at omor, anambra state, nigeria
Abstract
Mosquito larvae require an aquatic environment for breeding but the physico-chemical water parameters of any habitat may influence the survival and development of the species of mosquito larvae found in it. Mosquito larvae can breed in rice farms, hence rice farmers are potentially at risk of mosquito-borne diseases. A study to determine the physico-chemical parameters influencing mosquito larvae in two selected rice farms at Omor, Anambra State, Nigeria was conducted between May and August, 2017. Mosquito larvae were sampled with ladle dipper while physico-chemical water parameters (Temperature, pH, Total Dissolved Solids, Biochemical Oxygen Demand, Dissolved Oxygen, Total Suspended Solids, as well as Sulphate, Phosphate, Iron, Cadmium, Lead, Arsenic ion concentrations) were determined by standard methods. The mosquito larvae collected were reared to adult stages, and the 81 emergent adults were identified to species level using their external morphologic features. The same mosquito species were collected from both rice farms sampled but their total abundance Culex quinquefasciatus (46.83%), Culex tigripes (26.58%), Aedes albopictus (22.7%) and Mansonia africana (3.79%) was significantly different (χ2=13.736). Mosquito abundance and physico-chemical parameters, excepting pH, TDS and Sulphate, were negatively correlated. These findings suggest that rice farmers in Omor are at risk of mosquito-borne diseases transmitted by the identified species. Since the mosquito species encountered in this study have been shown by other workers to be potential vectors of human diseases, rice-farming communities in Nigeria should be beneficiaries of mosquito-borne diseases control interventions in the country.
