Termite- and mulch-mediated rehabilitation of vegetation on crusted soil in West Africa

The rehabilitation of vegetation on structurally crusted soils by triggerin g termite activity through mulch was studied on three soil types in norther n Burkina Faso, West Africa. A split-plot design was used in a fenced envir onment for the experiment. Insecticide (Dieldrin) was used at a rate of 500 g a.i. (active ingredient)/ha to create nontermite and termite plots. Thre e mulch types consisting of straw (Pennisetum pedicellatum), woody material (Pterocarpus lucens), and a composite mulch (straw and woody material) app lied at a rate of 3, 6, and 4 tons/ha, respectively, were used to trigger t ermite activity. The grasses and woody species on the plots were surveyed. Nontermite plots responded weakly to mulch treatments, but even in the firs t year vegetation established on termite + mulch plots. Termite activity re sulted in the increase of plant cover, plant species number, phytomass prod uction, and rainfall use efficiency. Infiltrated water use efficiency and p lant diversity were not statistically different among treatments during the first 2 years but were in the third. Woody species established only on ter mite plots. The three types of mulch plots showed greater vegetation develo pment than bare plots, which remained bare throughout the experiment. Analy sis of the termite and mulch interaction indicated that mulch plots without termites did not perform better than bare plots, especially in the case of woody plant regeneration. Vegetation rehabilitation was best with composit e and straw mulches with termites, followed by woody mulch with termites; i t was worst on bare plots.