Gully Erosion and Landslides in Southeastern Nigeria: Causes, Consequences and Control Measures

In southeastern Nigeria, soil and gully erosion and landslides are responsible for the widespread destructions of human, animal and plant lives, domestic, industrial and commercial property, transportation and communication systems, degradation of arable lands, contamination of surface and groundwater supplies, isolation of settlements and migration of communities. This account presents some of the results of research and studies of gully erosion and landslides carried out over the years in parts of southeastern States of Abia, Anambra, Enugu, Ebonyi and Imo States. Gully erosion is attributed to natural and anthropogenic causes, with the latter being most prevalent. Gully initiation is the result of localized erosion by surface runoff and soil eluviation associated with rainfall events of high intensity. Erosion is frequently concentrated where the forest cover has been removed for agricultural, urbanization and construction purposes and also at sites of uneven compaction of surface soils through surficial changes and movements. Based on rigorous reviews and research, interactions and personal experiences, the gullying mechanisms and processes were evaluated and the control measures suggested includes: avoiding human induced Soil/gully erosion initiation; public awareness; planting of vegetation on flood plains to be encouraged; laws guiding construction and building codes should be enacted by governments and relevant agencies; construction of special road infrastructure must be emplaced on solid engineering structures for soil and gully erosion control as well as regular maintenance of roads and drainages. Federal and State governments and community leaders should, therefore, inform and engage the inhabitants of the communities within the study area to successfully halt the initiation of gully erosion and landslide.

Keywords:Landslide; Erosion; Environmental disaster; Southeastern nigeria