Los sistemas silvopastoriles de Nothofagus antarctica contribuyen a la producción y fijación biológica de N en Patagonia sur, Argentina

Abstract

Most ñire forests in Argentine Patagonia has been used as silvopastoral systems. In these systems, white clover is a naturalised forage species that enhances livestock diet quality and also improve site quality through nitrogen inputs from biological fixation. This study aimed to evaluate white clover's biological nitrogen fixation (BNF) in silvopastoral systems and how it is affected under varying light, moisture, and soil quality conditions. For this, a trial was established at two sites using a split-plot design to assess forage biomass production, BNF, and N contributions under and between tree canopies. Significant interactions were observed between sites and canopy covers, and between sites and sampling dates. The highest BNF percentage occurred in the 'between canopies' condition at the less fertile site, with lower soil moisture during summer. However, the greatest N contribution in a particular site occurred under tree canopies, despite a lower BNF percentage, due to a larger legume biomass. The BNF percentage was primarily influenced by soil N availability and temperature.