Understanding the effect of an agroforestry system with high litter input on topsoil permeability

Abstract

AbstractSyntropic agroforestry systems (SYS) are a type of agroforestry in which very large amounts of organic matter (50–100 t ha−1 year−1) are added to the soil annually from pruning. However, information on the physical, chemical and biological effects of this management on soil is lacking. We characterized a SYS in terms of topsoil permeability (Mini‐Disk infiltrometer), soil organic matter (ignition method) and penetration resistance (Stolf penetrometer); we compared the results with those for a no‐till soy‐maize rotation and those within a native vegetation area (Brazilian Tropical Savanna), all on the same oxisol. The SYS had an infiltration capacity similar to that in the native vegetation area but which was higher than in the no‐till arable rotation. We relate this difference to both a lower penetration resistance and a high organic matter content in the SYS, possibly associated with higher litter input and with a greater above and belowground biomass. Our results indicate that SYS can be an efficient system for maintaining water infiltration at levels similar to those observed within natural ecosystems.