Assessment of water balance indices in Nigeria over two years with contrasting moisture condition
Keywords:
Water balance indices, actual evapotranpiration, potential evapotranspitraion, water deficit, water surplus.Abstract
A routine study of water balance is a veritable tool in monitoring the amount of water that will be available in the
soil of any particular place at a particular time for optimal crop production and other uses. This study assessed
water balance indices in Nigeria over two years with contrasting moisture condition. Mean monthly air
temperature and monthly rainfall data for 1983 and 2003 were sourced from the archives of the Nigerian
Meteorological Agency (NIMET) with respect to twenty-seven weather stations across Nigeria. The data were
subjected to Thornwaite’s and Climatic water budgeting procedure to estimate water balance indices such as
potential evapotranpiration, actual evapotranspiration, water deficit and water surplus. Paired sample test
revealed that there is a significance difference between the water balance indices of a dry year and a wet year
and across different locations in Nigeria [p=.000]. This study concluded that there is no uniformity in the pattern
of water balance indices across Nigeria for over two years. It is recommended that more functional irrigation
projects be established in those locations where water deficit is higher in order to boost their crop production
throughout the year in Nigeria.
