Ecological Characteristics and Functions of Histosols: Implications for Sustainable Wetland Management in Côte d’Ivoire

Abstract

This study examined the ecological characteristics and functions of Histosols in a floodplain of Songon Municipality, southern Côte d’Ivoire, to support sustainable wetland management. Morphological and pedological observations were carried out in two contrasting parts of the site: a hydromorphic zone, where a soil pit was described, and a shallow water zone, where an undisturbed soil core was collected using a PVC pipe. A composite sample from the 0–20 cm horizon was prepared from five subsamples collected from the four corners and the centre of the plot and was analysed for selected physicochemical properties. The field description identified hydromorphic conditions and organic horizons associated with water saturation. In the hydromorphic zone, two horizons were observed: a dark A1 horizon from 0 to 20 cm and an underlying Ag horizon from 20 to 40 cm, with the perched water table occurring at about 40 cm. In the shallow water zone, an O horizon from 0 to 15 cm and an H horizon from 15 to 35 cm were described, with visible partially decomposed roots. Laboratory results indicated the absence of mineral fractions in the analysed sample and showed high organic matter and organic carbon contents of 78.25% and 45.39%, respectively. The soil was acidic, with a pH of 4.72, total nitrogen content of 2.18%, a C/N ratio of 20.79 and a low cation exchange capacity of 3.42 cmol kg-1. Iron, potassium, zinc, calcium, aluminium and phosphorus occurred in low quantities. These findings indicate a peat-rich Histosol with important ecological functions, particularly carbon storage and water regulation, but with limited mineral fertility. Sustainable management should therefore consider both conservation requirements and carefully controlled agricultural use.