INVESTIGADORES
GHERMANDI luciana
artículos
Título:
Disentangling Fabiana imbricata (Solanaceae) regeneration: The
Autor/es:
LUCIANA GHERMANDI A,*, JORGELINA FRANZESE A, SOFÍA L. GONZALEZ A,
Revista:
JOURNAL OF ARID ENVIRONMENTS
Editorial:
ACADEMIC PRESS LTD-ELSEVIER SCIENCE LTD
Referencias:
Lugar: Amsterdam; Año: 2013 vol. 97 p. 9 - 13
ISSN:
0140-1963
Resumen:
In Mediterranean ecosystems, fire influences plant population dynamics and changes plant community
structure by affecting germination and establishment of seeder shrubs. Fabiana imbricata is a long-lived
seeder shrub with a broad distribution in South America. In Northwestern Patagonia grasslands there are
many records of F. imbricata recruitment after fires.We hypothesized that recruitment is promoted by: 1)
soil erosion that exposes deeply buried seeds; 2) direct fire effects such as heat that could break seed
dormancy; 3) indirect fire effects (i.e. increase of light availability and elimination of allelopathic substances)
and 4) water availability in spring. In field conditions, we tested the effects of shading and soil
disturbance on F. imbricata recruitment and seed availability and distribution in the soil profile. Under
controlled conditions, we investigated the influence of leaf leachate, light, heat and water on seed
germination and seedling emergence. Seed germination was inhibited by leachate, and seedling emergence
was inhibited by seed heated to 80 C and 120 for 5 min. F. imbricata seedlings only emerged in
germination treatments that simulated wet and very wet spring conditions. Fire and postfire wind that
favor seed exposure, combined with high precipitation early in the growing season, would be necessary
for successful shrub recruitment. When F. imbricata shrubland colonizes the grassland, it strongly
modifies local vegetation structure, reduces species richness and increases fuel loads. F. imbricata is a key
species in the ecosystem specially related to fire regime. Information on the postfire regeneration of this
species would provide valuable knowledge of the changes in biomass accumulation in a fire-prone
Mediterranean ecosystem.