Spatio-Temporal Variations of the Accumulated Litter on the Ground in the Loundoungou-Toukoulaka Forest Management Unit of Congo

Rykielle Grace Josene Mpikou, Yannick Enock Bocko, Freddy Dieu-Merci Mankou Mbika, Jean Joel Loumeto

Abstract: The functioning of tropical rainforests in the Congo Basin is still poorly understood, although their role in climate regulation has been reported for several years. The litter compartment, because of its important role in the transfer of nutrients and organic matter between the vegetation and the soil, contributes to the balance of these forest ecosystems and to the translation of the functioning of these ecosystems. However, there is little information on the forests of Northern Congo. This work focuses on the litter accumulated on the ground in order to contribute to the improvement of the knowledge of the functioning of the forests of North-Congo in general and those of the Loundoungou-Toukoulaka Forest Management Unit (FMU) in particular. Two forest types were chosen: a monodominant Gilbertiodendron dewevrei forest (GF) and a mixed forest (MF). The experimental set-up consisted of three square plots of one hectare each, subdivided into 25 plots of which 5 were selected for sampling. The method used was quarterly sampling of litter from 50 cm x 50 cm areas. The results obtained showed more litter accumulation in the G. dewevrei forest than in the mixed forest, varying respectively from 36.96 t/ha/yr to 25.12 t/ha/yr. These amounts are higher in the wet season than in the dry season for all litter components. However, there was no seasonal variation in woody organs. A weak correlation was observed between rainfall and the different litter components, except for GF reproductive organs.

Keywords: Ground litter, variations, rainfall, north Congo forest