Changes in channel width along the dasin-gereng segment of river Benue, Adamawa State, Nigeria

Abstract

This paper assesses the spatio-temporal adjustments in stream channel width in response to geotechnical characteristics along the Dasin-Gereng segment of River Benue. The active channel width of this segment of river Benue was measured on multi temporal satellite imageries (Viz LandSat MSS Images of 1975 and LandSat ETM Images of 1987 and 2005). ArCGIS 9.3 was used to undertake the extraction of the channel outlay and measurement of the channel width on the imageries. Paired t–test was used to compare changes in channel width for the 1975 –1987 and 1987 – 2005 and1975-2005 periods. The result of the Paired t-test suggests that there is a significant variation in channel width with t-values of 7.406 for 1975 –1987 period, -2.76 for 1987 – 2005 period and 3.015 for 1975-2005 period. Based on the findings of this study, it is recommended that a buffer zone be established along the bank line of the segment with a view to stabilizing the bank.

Key Words: Bank material, Dasin-Gereng, Channel Adjustment, Channel Segment, River Benue, Urban Settlement.