Restoration of fertility of gleyic fluvisols to increase rice yields using shellfish products in Toumbokro, Cote dIvoire

A study designed to characterize the effects of shellfish products on the chemical properties of fluvisols gleyic and yield of rice was carried out in Toumbokro, Yamoussoukro’s region, Côte dIvoire. The work has been focused on soil amendment by three types of shells (Achatina spp Donax sppand Ostrea spp). Three doses of shellfish products (500, 1000 and 1500 kg.ha-1) and NPK fertilizer were tested in a split-plot design with three repetitions. At ground level, the study showed that the shellfish products have positive effects very marked on all the physical and chemical characteristics. The effects of these shellfish products on the richness of the soil occur gradually. The increase of pH, due to the products made, creates a condition favorable to microorganisms that become active and mineralize sufficient organic substances. The study indicates that shellfish products induce high levels of production of rice cultivation. The average of yield of the experiments carried out is set at 5.41 t.ha-1 in Toumbokro. These performances, never recorded in-subsistence agriculture, are explained by the effective correction of mineral deficiencies unsuspected soil by the flow of shellfish products. All the variables studied define the contribution of 1000 kg.ha-1 shredded shells of Achatina spp, as the optimum for soil amendment.