The influence of three soil management systems and two vegetative covers on water infiltration into a Yellow Latosol from Manaus, AM, Brazil

Abstract

A field study was conducted at the Centro Nacional de Pesquisa de Seringueira e Dendê (CNPSD) at Manaus, AM, Brazil, to evaluate the effects of three management systems and two vegetative covers on the infiltration of water into a heavy clayey Yellow Latosol. Equilibrium infiltration rates were much higher under rubber with tropical kudzu (Pueraria Phaseoloides Benth.) and virgin forest treatments (28.5, 22.7 and 22.3 cm/hour, respectively) than under rubber with grass (3.3 cm/ hour), and rubber x coffee treatments (5.9 cm/hour). The higher infiltration rates of soils under the three first systems were due to changes in soil physical conditions brought about by their respective covers. The comparatively low values of infiltration rates of rubber with grass and rubber x coffee systems, on the other hand, were attributed in the first case to wheel-induced soil compaction as a result of excessive machinery traffic, and to lack of a vegetative cover to protect the soil and enhance good tilth in the rubber x coffee intercropping system. These results emphasize the beneficial effects of canopy covers, when adequately managed, on the preservation and/or improvement of the physical condition of the soil which in turn reduces erosion and runoff hazard.