Analysis of Selected Failed Gully Erosion Control Works in Imo State
Gully erosion constitutes the major ecological problem in southeastern Nigeria and requires adequate scientific and proper technical competence in the prevention and control of this menace. An effective control of any phenomena is not possible unless and until the principles and mechanics underlying its behaviour and distribution over time and space are fully understood. Β The objective of this paper is to present some examples of gully erosion control works and the effectiveness of the corrective measures put in place in Imo State. The study revealed that the initiation and development of erosion gullies is facilitated by natural processes (rainfall, topography engineering-geological properties of soils, especially texture, etc) and the activities of man, especially road construction. However, incorrect information, incomplete data or wrong concepts in the application of either method of erosion control have aggravated gully erosion problems. Many of the erosion control measures put in place in Imo State show that hydrological variables (e.g. runoff) which constitute major factors in soil erosion, were not considered in the design and has resulted in deep gullies, instead of checking erosion.
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