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

Abstract

Syntropic 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.

Topsoil physical properties under a riparian forest in Central Brazil: infiltration and penetration resistance

“…Such increase has previously been documented for a forest within the Brazilian savanna (see Pereira et al 2021). Our resistance to penetration was lower compared to a nearby savana (regionally known as "Cerrado típico") in the same area (Murta et al 2020). Such difference of soil penetration resistance in the riparian forest compared to a savanna might be attributed to the higher and more continuous addition of litter year-round in the forest compared to the savanna (Costa et al 2020).…”

“…Data analysis -Sample sufficency was verified for infiltration capacity using a simple plot of mean and standard deviation versus number of samples. An adequate sample size was considered met when central tendency statistics stabilized for at least three times consecutively (Salemi et al 2020). Residuals of soil penetration resistance were subjected to Shapiro-Wilk test which indicated a lack of gaussian distribution.…”

How does land use cover change affect hydrological response in the Atlantic Forest? Implications for ecological restoration

“…The region is subject to a negative tradeoff that represents a faster increase in evapotranspiration due to increased leaf cover and a gradual improvement in soil water infiltration conditions (Ferraz et al, 2020). In these regions, the recommendation is to identify critical regions in relation to water availability considering climatic conditions (Ponce et al, 2000) and local conditions (of Assis et al, 2011) and, in these areas, give focus more on the restoration of riparian strips aiming at water quality (Souza et al, 2013;Piffer et al, 2021) and adoption of techniques that allow better evolution of soil structure and lower evapotranspiration rates such as agroforestry systems (Murta et al, 2021).…”

Do agroforestry systems improve soil functioning? a comparison with other land uses

“…Increased infiltration rates were found by Murta et al (2021) on an Ferralsol/Oxisol under a agrosilvicultural AF when compared to no-tillage soy-maize rotation system. using computed tomography technics found higher Total Porosity and Macroporosity under agroforestry buffers than under row crop, besides finding lower Bulk Density and higher Saturated hydraulic Conductivity under AF.…”