Siembra de pastos nativos para la restauración productiva de pastizales naturales en el sudoeste bonaerense

Abstract

Los pastizales pampeanos están altamente degradados por la agricultura y el sobrepastoreo. Este estudio evaluó la siembra de especies forrajeras nativas para su restauración en el Sudoeste Bonaerense. Se compararon ocho especies nativas con Thinopyrum ponticum (agropiro). Nassella neesiana y N. longiglumis mostraron la mayor emergencia (>75%) y establecimiento, superando al agropiro. Ensayos con diferentes densidades de siembra (200, 350 y 500 semillas/m²) revelaron que densidades más altas incrementan plántulas, pero no siempre el establecimiento final. Ambas Nassella superaron el 10% de establecimiento mínimo recomendado. Se recomienda sembrar a 350–500 semillas/m², priorizando especies nativas con semillas grandes para una restauración eficiente y escalable.The pampas grasslands are highly degraded by agriculture and overgrazing. In the southwest of Buenos Aires, where livestock production in pastures is predominant, overgrazing has displaced key forage species, reducing productivity and affecting biodiversity and ecosystem services (Di Bella et al., 2019). In this context, ecological restoration emerges as a crucial tool, and the appropriate selection of species is critical to its suc- cess. This study evaluated the planting of native forage species for restoration in the southwest of Buenos Aires. Eight native species were compared with Thinopyrum ponticum (wheatgrass). Nassella neesiana and N. longiglumis showed the highest emergence (>75%) and establishment, surpassing wheatgrass. Trials with different planting densities (200, 350 and 500 seeds/m2) revealed that higher densities increase seedlings, but not always the final establishment. Both species of Nassella exceeded the 10% minimum recommended establishment. It is recommended to sow at 350–500 seeds/m2, prioritizing native species with large seeds for efficient and scalable restoration.