Tropicultura (Jan 2013)
Effets de la fragmentation des forêts par l'agriculture itinérante sur la dégradation de quelques propriétés physiques d'un Ferralsol échantillonné à Yangambi, R.D. Congo
Abstract
Effects of Forest Fragmentation by Shifting Agriculture on the Degradation of some Physical Properties of a Ferralsol Sampled at Yangambi, D.R. Congo. The knowledge of changes occurring in the soil cover at the forest edge is needed to better understand the impact of forest fragmentation on soil parameters. The objective of this study is to evaluate the effects of forest fragmentation caused by shifting agriculture on texture, bulk density, total porosity and soil hydraulic conductivity in the layers at 0-10, 10-20 and 20-30 cm depth by the transect method in a perspective of sustainable land management in the region of Yangambi. The results obtained show that the edge between the fallow grassland and dense forest has a width of 70 m. Degradation of all the physical properties of soils relative to the dense forest is very significant (p<0.01) for the studied layers. Fragmentation of forests by shifting cultivation increases the phenomenon of selective loss of clays of the surface soil layers and consequently increases its bulk density and decreases the permeability and porosity with depth under the fallow grass and edge. The texture data associated with textural classes in the FAO textural triangle indicate a change in texture of the soil under different land uses for the tree layers studied.