Efecto de la labranza sobre la materia orgánica y la actividad enzimática de un inceptisol venezolano

In Venezuela, information about the effect of agricultural management on microbial properties of soil is scarce. Because of this, it was studied the effect of tillage and plant residue use on the organic carbon (OC) content, fulvic and humic acid ratio (FA/HA), and phosphatase acid (PA) and dehydrogenase activity (DA) of an Inceptisol located in Guanare, Portuguesa State. Four treatments were applied: reduced tillage with residue use; reduced tillage without residue use; no-tillage with residues use and no tillage without residue use. The results indicated that, soil with low OC content, and slightly acid pH, the soil OC content and the PA and DA activities were increased, at least temporarily, as a consequence of treatment, particularly when organic residues were used in the absence of tillage. No significant decrease of FA/HA ratio was observed for the notillage treatment.