Seed regeneration in native forests of Nothofagus antarctica under silvopastoral use in Southern Patagonia, Argentina

Abstract

The aim of the present study was to evaluate the effect of silvopastoral use in two pure stands of Nothofagus antarctica (ñire, ñirre) growing at two site qualities on the regeneration cycle from production and quality of seeds, and the establishment and mortality of seedling in Southern Patagonia (Argentina). To evaluate seed production four traps were distributed to capture the spatial variation of each stand during seven years (2004-2010). Also, seed viability and germination were evaluated. In each site, permanent sampling plots were used to measure seedling establishment and mortality. Seed production in stands under silvopastoral use varied from 1 to 40 million seeds ha^-1, with no differences compared to seed production in surrounding primary forests of the same site quality. Stands under silvopastoral use showed that seed quality varied among sites being higher in the lower site quality. However, there was no difference in seed quality between silvopastoral use and primary forests stands. Seedling establishment was improved in the stands under silvopastoral use compared to primary forests, but mortality rate was high (or total) in all situations. We concluded that silvopastoral use of the studied stands did not modify substantially seed regeneration compared to primary forests.