Variation in runoff and sediment loss in fallow and abandoned farmland in Agoi- Ekpo, Cross River State, Nigeria

Abstract

A study was carried out to assess soil erosion and associated losses on abandoned cassava farmland, 3-year, 10-year and 5-year fallows in a part of the rainforest zone of southern Nigeria. The study showed that the 5- year fallow yielded the most losses as a result of its scanty herbaceous cover and existence of canopy gaps followed by the abandoned cassava farmland, while the 10-year experienced the lowest losses in runoff and sediment. Runoff loss (F = 16.089; p<0.05) and sediment loss (F = 6.355, p<0.05) varied significantly among the treatments. The study revealed erosional losses occurred in all plots and that fallows with sparse herbaceous cover were less effective in suppressing soil erosion. To reduce unproductive loss of rich topsoil, farmers were encouraged to maintain adequate herbaceous cover during cropping to speed up ecological restoration after land abandonment.

Keywords: Fallow vegetation, Soil erosion, Erosional losses