Effects of fire and water availability on the emergence and

CASILLO, J.; KUNST C.; SEMMARTIN M

AUSTRAL ECOLOGY

WILEY-BLACKWELL PUBLISHING, INC

Año: 2012 vol. 37 p. 452 - 459

1442-9985

Abstract In the semiarid Chaco savannas, the balance between herbaceous and woody species affects landscapeconfiguration and ecosystem services such as forage production.Therefore, understanding the factors that controlthis balance is crucial for management. In a factorial experiment, we assessed the effects of fire and water availabilityon the emergence and recruitment of grasses, forbs and woody species.The results showed that the effects of fireand water availability on early regeneration stages differed among the three functional groups. For grasses, fire andwater addition enhanced emergence when acted solely, but only the positive effects of fire were translated intoa greater recruitment, irrespective of the water availability. For forbs, only water addition, when acted solely,promoted the emergence, although this effect was not translated into a greater recruitment. Lastly, in the case ofwoody species, both fire and water addition reduced emergence and recruitment. Our results support the notionthat both fire and greater water availability would contribute to the maintenance and recovery of a grass-dominatedstate of vegetation through a positive effect of fire on grasses recruitment and a general negative effect of fire andwater on woody species emergence and recruitment.