IMBIV   05474
INSTITUTO MULTIDISCIPLINARIO DE BIOLOGIA VEGETAL
Unidad Ejecutora - UE
artículos
Título:
Fire incidence along an elevation gradient in the mountains of central Argentina
Autor/es:
BELLIS, LM; CINGOLANI, AM; ARGAÑARAZ, JP; GIORGIS, MA
Revista:
ECOLOGÍA AUSTRAL
Editorial:
ASOCIACIÓN ARGENTINA DE ECOLOGÍA
Referencias:
Lugar: Buenos Aires; Año: 2020 vol. 30 p. 268 - 281
ISSN:
0327-5477
Resumen:
ABSTRACT. In mountain ecosystems, vegetation distribution along elevation has been traditionally interpretedin terms of the decreasing temperature from base to top, but wildfires may co-vary with the elevation gradient,also playing an important role. In the mountains of central Argentina (500-2800 m a. s. l.) wildfires are one ofthe main disturbances, which may have an important role in shaping vegetation dynamics along elevation.However, to date, no study described the fire pattern along the elevation gradient. We compared fire incidenceamong five elevation intervals using an 18-year spatially explicit fire database derived from remote sensing.For each interval, we discarded unburnable areas and calculated fire incidence per year as the percentage ofburned area. Fire incidence showed a hump-shaped pattern along the elevation gradient. The highest fireincidence occurred at intermediate elevations, in the 1301-1700 m and 901-1300 m intervals, with averages of3.2 and 2.7% of the area being burned annually, respectively. The lowest fire incidence occurred at the lowestinterval (500-900 m), with 1.3% being burned annually on average. The greater fire incidence observed atintermediate elevations is consistent with a sharp increase in the cover of grasslands above 900 m a. s. l., withan associated reduction in forest occupation. Towards higher elevations, the lower fire incidence is consistentwith the presence of topographic breaks, greater proportion of unburnable surfaces that work as firebreaksand moister conditions. The greater fire incidence observed at intermediate elevations may be limiting forestexpansion in those areas. At higher elevations the low forest cover may be explained by a combination of fireand livestock pressure. Our study is the first to show how fire incidence varies along the complete elevationgradient, bringing an important tool to understand vegetation distribution and plan future conservation andrestoration strategies.