INVESTIGADORES
FARJI-BRENER Alejandro Gustavo
artículos
Título:
Exotic thistles increase native ant abundance through the maintenance of enhanced aphid populations
Autor/es:
LESCANO, N.; FARJI-BRENER, AG
Revista:
ECOLOGICAL RESEARCH
Editorial:
SPRINGER TOKYO
Referencias:
Año: 2011 p. 827 - 834
ISSN:
0912-3814
Resumen:
Exotic species change the structure and composition
of invaded communities in multiple ways, but
the sign of their impact on native species is still controversial.
We evaluated the effects of the thistles
Carduus thoermeri and Onopordum acanthiumtwo of
the most abundant exotic plant species in disturbed
areas of the Patagonian steppeon the native tending
ant assemblage. Exotic thistles showed an increased
number of plants with aphids and had greater aphid
density than native plants. Since native tending ants
were present only in plants with aphids, their abundance
was higher in infested thistles than in native plants. Path
analyses confirmed that ant activity depended more on
aphid density than on thistle traits. Our results suggest
that the presence of exotic thistles in disturbed areas of
NW Patagonia indirectly benefit the native ant assemblage
through the maintenance of an increased aphid
population. This illustrates how the impact of exotic on
native species can depend on the ecological context.