DETERMINATION OF VEGETATION AND RELIEF THRESHOLDS FOR GULLY INITIATION IN KEREKE WATERSHED OF THE LOWER BENUE TROUGH

Gully erosion is a serious environmental problem causing lot of havocs to the globalenvironment including Kereke Watershed of the Benue Trough. This study therefore determinesthe thresholds of vegetation and relief parameters as intrinsic threshold factors for gullyinitiation in the Kereke Watershed of the Benue Trough, to enhance gully erosion control. Thesystematic sampling procedure was used to select thirty-two settlements in the study area ascatchment areas for data collection. Data on vegetation, relief parameters and gullyintensity/frequency were collected from direct field measurements and participatoryobservation. Percentages and means were used to depict variations in the data set. Plot scattergraphs were used to establish the relationship between vegetation, relief and gullyfrequency/intensity to determine threshold values for gully initiation. Findings of the studyshows that the critical thresholds of 69% for vegetation cover, 5cm for depth of litter cover, 2ofor valley slope angle and 71m for elevation above sea level, are essential for gully initiation inthe Kereke Watershed. The study established that Kereke watershed exceeded the thresholdvalues of vegetation cover, depth of litter cover and slope gradient for gully initiation, andtherefore gullies were incised in some parts of the watershed. It is therefore recommended thatgovernment and individuals should engage in afforestation by planting of trees to help improvevegetal cover, depth of litter cover and slope stability in the study area.This will help to reducethe intensity of gully initiation in the study area for enhanced environmental management.