EXECUTIVE SUMMARY
The menace of erosion globally has a huge impact on the socio-economy of areas were they exist. This is also true for Nigeria where the high number of erosion sites, particularly in the south eastern parts of the country had severe socio-economic impacts including the loss of land, properties, biodiversity and contribution to climate change. As a result, the Federal Government of Nigeria (FGN) in its commitment to transform the Nigerian socio-economy with the help of the International Development Association (IDA) implemented the Nigeria Erosion and Watershed Management Project. The Nigeria Erosion and Watershed Management project (NEWMAP) is an 8-year multi-sectorial and multi-scale program that targets States with acute gully erosion, including Abia, Anambra, Cross Rivers, Ebonyi, Edo, Enugu and Imo States. These States constitute the target intervention for the first phase of the project.
This project is aimed at developing a geographic information system for watershed and land use/land cover dynamics and remote sensing in NEWMAP Phase 1 intervention States. Based on this aim, the following objectives were achieved in this project: acquisition of satellite images covering the seven States; pre-processing of the satellite images acquired; extraction of informational classes from the processed satellite images; visitation to the project areas to collect sample points for the validation of the informational classes extracted; development of Landuse and Landcover dynamics over a period of 14 years (2000 t0 2014), and the development of digital elevation model for the study area.
Results from the study show that the major causes of erosion in these States are majorly anthropogenic activities followed by soil exposure due to increase in construction of buildings roads and other infrastructures. It also revealed that erosion sites are surrounded by high elevations indicating that these areas are lower catchment areas where runoff flows into from higher areas.
Finally, this report lays out a series of recommendations including proper channelling and termination of drainage construction for road construction and water supply schemes to prevent washing off of soil surfaces exposed during such construction works and periodic assessment of land use changes using remote sensing land use dynamics assessment to assist in monitoring and evaluating land use changes that could lead to the development and growth of erosion scourge in Southeast Nigeria. In addition, capacity development of the NEWMAP technical staffs in the seven States was recommended so that the products developed in this project could be used by the States. Similar capacity building had been conducted for NEWMAP staffs at the federal level by the National Space Research and Development Agency.
