INVESTIGADORES
FARJI-BRENER Alejandro Gustavo
artículos
Título:
Succession of ground-dwelling beetle assemblages after fire in three habitat types in the Andean forest of NW Patagonia, Argentina
Autor/es:
SASAL, YAMILA; RAFAELLE, ESTELA; FARJI-BRENER, ALEJANDRO GUSTAVO
Revista:
JOURNAL OF INSECT SCIENCE
Editorial:
UNIV ARIZONA
Referencias:
Lugar: Arizona; Año: 2010 vol. 17 p. 1 - 17
ISSN:
1536-2442
Resumen:
Wildfires are one of the major disturbances in the dynamics of forests and shrublands. However, little is known about their effects on insect communities that contribute to faunal biodiversity and play key roles in the ecosystem’s dynamics. An intense and widespread fire occurred in 1999 in the Nahuel Huapi National Park in the Andean forest in northern Patagonia, Argentina. The fire affected adjacent, but different, habitat types. After the fire, beetle abundance, species richness and assemblage composition were compared among three habitats that were structurally different before the fire. These habitats were: 1) lowland rain forests dominated by the evergreen Nothofagus dombeyi (Mirb.) Oerst. (Fagales: Nothofagaceae), with an understory of Chusquea culeou Desvaux (Poales: Poaceae), 2) a mixed forest of the evergreen conifer Austrocedrus chilensis Florin & Boutejie (Pinales: Cupressaceae) and N. dombeyi and 3) a shrubland with a diverse community of shrub species. The relationship between beetle diversity and vegetation structure was investigated over three consecutive years. Ground beetles were collected by pitfall traps, and plant species richness, vegetation cover, and height were measured during three consecutive growing seasons. Beetle communities varied more over years than between habitats during the early regeneration after fire. There was a shift in beetle assemblage composition with time after the fire in all habitat types, probably due to similar colonization rates and microclimatic conditions. Therefore, beetle succession was more influenced by recolonization and survivorship, accompanied by climatic conditions and recovery rate of plant communities over time, than it was influenced by pre-fire habitat conditions. These results suggest that in NW Patagonia, wildfire can have a substantial, short-term impact on beetle abundance and species composition. The pre-fire conditions of each habitat type determined the structure of post-fire communities of plants but not beetle assemblages. Wildfires produce simplification and homogenization of habitat types, and this was reflected by beetle diversity.