Native tree regeneration in native tree plantations: understanding the contribution of Araucaria angustifolia to biodiversity conservation in the threatened Atlantic Forest in Argentina

MEDINA MICAELA; PEREZ FLORES MAGALI; GOYA JUAN FRANCISCO; CAMPANELLO PAULA INES; PINAZO MARTIN ALCIDES; RITTER LUIS JAVIER; ARTURI MARCELO FABIAN

AUSTRAL ECOLOGY

Ecological Society of Australia

Año: 2020 vol. 45 p. 229 - 239

1442-9985

Abstract Deforestation is a global process that has strongly affected the Atlantic Forest in South America,which has been recognised as a threatened biodiversity hotspot. An important proportion of deforested areaswere converted to forest plantations. Araucaria angustifolia is a native tree to the Atlantic Forest, which has beenlargely exploited for wood production and is currently cultivated in commercial plantations. An important questionis to what extent such native tree plantations can be managed to reduce biodiversity loss in a highly diverseand vulnerable forest region. We evaluated the effect of stand age, stand basal area, as a measure of stand density,and time since last logging on the density and richness of native tree regeneration in planted araucariastands that were successively logged over 60 years, as well as the differences between successional groups in theresponse of plant density to stand variables. We also compared native tree species richness in planted araucariastands to neighbouring native forest. Species richness was 71 in the planted stands (27 ha sampled) and 82 innative forest (18 ha sampled) which approximate the range of variation in species richness found in the nativeforests of the study area. The total abundance and species richness of native trees increased with stand age andtime since last logging, but ecological groups differed in their response to such variables. Early secondary treesincreased in abundance with stand age 3?8 times faster than climax or late secondary trees. Thus, the change inspecies composition is expected to continue for a long term. The difference in species richness between nativeforest and planted stands might be mainly explained by the difference in plant density. Therefore, species richnessin plantations can contribute to local native tree diversity if practices that increase native tree density areimplemented.