Effects of fire severity on early recovery of Patagonian steppes

GHERMANDI, LUCIANA*; GONZALEZ, SOFÍA; LESCANO, MARÍA NATALIA, AND ODDI FACUNDO

INTERNATIONAL JOURNAL OF WILDLAND FIRE

CSIRO PUBLISHING

Lugar: Collingwood; Año: 2013 p. 1055 - 1062

1049-8001

Fire severity affects the recovery and biodiversity of plant communities. We compared the early post-fire recovery of plant functional groups in two sites (one burned with high severity and one with low severity) in the northwestern Patagonian steppe. We sampled the post-fire soil seed banks, as well as the composition and cover of aboveground plant species, and calculated richness, diversity, and the percentage of exotic species. Low fire severity increased the diversity of aboveground vegetation and seed banks, while high fire severity reduced the cover of all functional groups, with the exception of fugitive species. Tiller production of perennial grasses decreased due to bud bank mortality. In the seed bank, high severity fire reduced fugitive species and increased exotic species. Fugitive species need fire to recruit, and the combination of fire cues and post-fire environmental conditions can explain the high abundance of these species after fire. It would be difficult to use the results of this study to improve the management of steppe vegetation because fire is considered dangerous. However, Northwestern Patagonia is sparsely populated and the frequent wildfires are not dangerous for the population. It is necessary to increase the knowledge of the ecological processes of Patagonian ecosystems related to fire regime and land use to achieve a reasonable balance between sustainable use and conservation in this region.