Newly implemented crop-livestock-forest systems increase available water and aeration in soils of the Brazilian Savannah

Abstract

There is a growing demand for cropping systems that guarantee food production by improving the use efficiency of natural resources such as soil and water. The crop-livestock-forest (CLF) system is a form of sustainable intensification in which biodiversity and yields are increased on the same area. In this study, the physical-hydric properties of a Ferralsol and Cambisol in Central Brazil within the Savannah biome (Cerrado) were investigated 2 and 1 year after implementation of CLF systems. Soil samples were collected at seven soil depths up to 1 meter deep in CLF systems, within and between rows of trees, in a native forest (NF) and in a non-cultivated pasture, which was used as a reference (P-REF) for comparing soil quality with CLF establishment. Statistical analysis of soil water retention capacity considered two soil layers, 0.0-0.3 and 0.3-1.0 m, using clay and gravel contents as covariates in a mixed model. Main differences were noted within 0.0-0.3 m soil layer. In the Ferralsol, the available water was 0.2-0.3 mm higher in the CLF than in the P-REF, mainly due to an improvement in Theta R and microporosity. The Cambisol, in turn, showed in CLF and in NF a higher aeration capacity by up to 0.3 m3 m-3 than in P-REF, as indicated by the Theta S and macroporosity values. The S index values showed that CLF can improve soil physical quality of light textured soils such as Cambisol in the short term compared to P-REF. This improvement in soil quality is key to sustaining food production under tropical conditions.

Keywords

• soil water retention capacity
• pasture
• eucalyptus trees
• integration