Environmental assessment of gully erosion in parts of Enugu north, Southeastern Nigeria

Abstract
Objectives: To assess gully erosion in parts of Enugu north, Southeastern Nigeria using some geotechnical parameters. Method: The soil samples were collected from different gully point and some geotechnical parameters was analyzed in Soil Science Department, University of Nigeria in accordance with the specified standard procedures. Finding: The assessment of gully erosion inparts of Enugu north, southeastern Nigeria, has been carried out. Soil samples were collected from the four major gully points, at the depth range of 0.5 to 1.0m using soil auger, core samplers and hammer. The soil classification shows that the textural characteristics were predominantly sandy, loamy and clayey. Liquid limit (LL) ranged from 16.67 to 46.89%. Plastic limit (PL) was 33.45% in Igbo-Eze South and 22.38% in Nsukka. None plastic limit were observed in Igbo-Eze North and Udenu. Percentage plasticity index (PI) of 13.44% was depictedin Igbo-Eze South and 9.90% in Nsukka. Zero plasticity indexes were noted in Igbo-Eze North and Udenu. Bulk density test ranged from 1.39 to 1.56 g/cm3. Porosity ranged from 41.13 to 47.55%. The hydraulic conductivity and moisture content are ranged from 8.89 to 22.73 m/day and 7.07 to 31.73% respectively.These results indicate presence of coarse sand, fine sand, low amount of clay and silt in small proportion, loosed soil with low binding materials, instability of soil structure, low moisture content and other bio-activities that contribute to the rate of increase of gully erosion in the study area. Novelty : The estimated geotechnical parameters, including Atterberg limit (plastic limit, liquid limit and plasticity index), hydraulic conductivity of the soil, soil aggregate stability, particle size distribution, bulk density, total porosity proffers solutions to the gully problem in the area. Keywords: Enugu north; gully erosion; geotechnical