The Marantaceae family constitutes a bio-indicator of natural forest perturbation. The present study was undertaken with the aim of elucidating the origin of these inhabited herb kinds in the mature Yoko forest stack. The pedoanthracological approach was used to search for the under soil Marantaceae perturbation indicators, to determin their age by the 14C dating and lastly, evaluate the perturbations, incidences on the vegetation of the current forest of the region. Four soil pit excavation established in the Marantacea forests permitted to identify two indocators: the Charcoals and pieces of the ceramic. The analysis of these indicators coupled to the story of the region of the last centuries: (i) the fossil charcoals result either from the burn intinerant agriculture or from the household fire; (ii) the pottery comes from the kitchen ustensils that the human kind used for his survival needs. The Charcoals from de pits which have 14C dating indicate the ancient fire dated 1125 ± 30 years BP and the contemponary fire of 350 ± 30 to 145 ± 30 years BP. These perturbations have got an impact on the actual floristic riches. For some identified taxa like Gilbertiodendron dewevrei (De Wild.) J. Léonard, Monodora sp, Tetraberlinia bifoliata J. Léonard, Pouteria sp, Homalium longistylum Mast, Turraeanthus africanus Welw ex C.DC.) Pellegr), their fossil charcoals were not found in the actual Marantaceae forests.

Food and feeding habits of Hippopotamyrus psittacus (Boulenger, 1897; Pisces: Mormyridae) of Congo river has been undertaken from February to July 2007 by the stomach contents analysis. 44 H. psittacus ranging from 55 to 320 mm of length were captured in the Congo River (Wagenia Falls and Kikongo beach). The total length, the standard length and height of the body were measured with a ribbon meter and weighed using both bood scales of 0- 3000gr. Afterward, stomach contents were taken and conserved in the Laboratory for future analysis. Stomachs contents were examined using a binocular magnifying glass LEICA WILDHEERBRUGG Mg model with a magnification of 10 to x50. The stomachs contents analysis showed that H. psittacus is a carnivorous with an insectivorous tendency by feeding mainly on aquatic insects and other animals remnants. On the other side, the food regime of H. psittacus appeared more diversified during the relatively dry season periods. On the same way, the average stomach contents weight indicates that the feeding activity is more or less different during different season periods with an increasing feeding activity during the relatively dry season periods.