Growth and productivity of Eucalyptus benthamii in integrated crop–livestock systems in southern Brazil

Abstract

Integrated crop–livestock systems (ICLS) are production models that promote sustainable intensification and integrate agricultural and forestry production systems, generating a combination of economic and environmental benefits. Knowledge is still scarce about the growth and productivity of the tree component in ICLS, and there is a lack of long-term landscape-scale assessments about the provision of ecosystem services in ICLS. Our objective was to evaluate the monthly stem volume increment and productivity of Eucalyptus benthamii, at 7 years old, using metal dendrometer bands, for three different models of ICLS that integrate trees to the crop (crop–forestry—CF), livestock (livestock–forestry—LF), or both (crop–livestock–forestry—CLF) in southern Brazil. The form factor decreased while increasing age, with 0.516 at 4 years and 0.437 at 6 years after planting. In ICLS, we found the productivity of E. benthamii similar to the national averages for monoculture forestry in the United States and Brazil. At 6.5 years after planting, the average annual stem volume increment was 22.7 m³ ha⁻¹ year⁻¹ (LF), 24.6 m³ ha⁻¹ year⁻¹ (CLF) and 25.5 m³ ha⁻¹ year⁻¹ (CF), respectively. The CF production system provided trees with greater accumulated stem volume within 7 years of age. The LF system, on the other hand, provided trees with an equal increment in diameter, but less accumulated stem volume, and, therefore, smaller heights, suggesting that there is interference from cattle and pasture management on the growth and productivity of E. benthamii. ICLS are configured as an excellent possibility for vertical expansion of agricultural frontiers, promoting sustainable intensification, as well as can prevent horizontal expansion into new areas, reducing pressure on native forests, and contributing to combating deforestation.