Trend in ground water fluctuation in Gidan Kwano Inland Valley of Niger State Nigeria

摘要

Trend in ground water table fluctuation was investigated on an experimental field of 18070.2 m2between June and March of a following year. Five Piezometers were used to monitor the depth of water table at different locations. Findings indicated a depth of water table fluctuation between 0.4 cm above the soil surface and 200 cm below surface. Further analysis carried out on possible relationship between depth of water table and time indicated a non linear polynomial of second order degree (Y =a + b1X + b2X2) with 0.84 as the average regression coefficient (R2). Trend in depth of water table (from ground surface) decreases with increasing rainfall from July to September but increases from September to March as rainfall decreases from September to November. Nevertheless, the sharp decline in rainfall between September and October do not translate to increase in depth of water table, this could be due to over saturation of soil in September that recharged the valley in October. The relationship between rainfall and depth of water table from the ground surface is statistically significant with regression coefficient of 73%.