From forest to shrubland: Structural responses to different fire histories in Prosopis flexuosa woodland from the Central Monte

CESCA, E.M.; .VILLAGRA, P.E.; ALVAREZ, J.A

JOURNAL OF ARID ENVIRONMENTS

ACADEMIC PRESS LTD-ELSEVIER SCIENCE LTD

Lugar: Amsterdam; Año: 2014 vol. 110 p. 1 - 7

0140-1963

In many ecosystems, fire modifies the population structure of woodland species through changes in their natural regeneration and growth habit. The objective of this study was to analyze the current structure of P. flexuosa woodlands with seven different fire histories in the Central Monte. The structure of stems showed that unburned woodland and woodlands with longest post-fire recovery time presented higher proportion of stems with basal diameter (BD) > 5 cm , whereas on sites with higher recurrence of fire there were very few stems with BD > 5 cm and many stems/ha with BD < 5 cm . Tree height and crown diameter showed a significant decrease at sites recently burned or with high fire recurrence. All woodlands studied present a good health status. The data analyzed in this study suggest that P. flexuosa woodland structure in the southeast of Mendoza is strongly controlled by its fire history. Fire generates an environment dominated by individuals with numerous smaller-sized stems, which becomes more evident in environments where fire recurrence is higher. Structural changes induced by fire indicate that logging may not be possible in the area, necessitating development of techniques for post-fire management of the burned areas. Based on the factors that predispose to fire and on models of climate change, an increase in fire frequency is to be expected in the area, and therefore a modification of the population structure of P. flexuosa, leading to woodland conversion to shrubland and loss of capacity for natural recovery.