Seasonal variations of live moisture content and ignitability in shrubs of the Mediterranean Basin
G. Pellizzaro A B , P. Duce A , A. Ventura A and P. Zara AA Institute of Biometeorology, National Research Council (CNR – IBIMET), Via Funtana di lu Colbu 4/a, I-07100 Sassari, Italy.
B Corresponding author. Email: g.pellizzaro@ibimet.cnr.it
International Journal of Wildland Fire 16(5) 633-641 https://doi.org/10.1071/WF05088
Submitted: 21 September 2005 Accepted: 10 August 2007 Published: 26 October 2007
Abstract
The objectives of the present study were (i) to describe the seasonal pattern of ignition delay (ID time) and moisture content of live fine fuel (LFMC) for eight common shrub species of the Western Mediterranean Basin, and (ii) to evaluate the relationships between LFMC and ignitability. The experiment was carried out in a shrubland area located in Sardinia, Italy. LFMC and time to ignition or ID time values were determined monthly or twice a month throughout the year. Ignitability was determined by laboratory tests. Meteorological data were also collected from a weather station located in the study area. Significant linear regression equations of ID time v. LFMC were found for most of the species, with R2 values ranging from 67 to 94%. In general, very low values of ID time were observed when LFMC ranged from 70 to 100%. In addition, two groups of species were identified, depending on seasonal changes of both LFMC and ID time (or ignitability): (i) species with LFMC not greater than 100% and high ignitability values all throughout the year, and (ii) species with large seasonal variability of LFMC and ignitability values that were low in winter and high in summer. Significant differences in ignitability among species were also observed.
Additional keywords: forest fuel, live fuel moisture, maquis species, Mediterranean vegetation, time to ignition.
Acknowledgements
The authors wish to acknowledge the Regional Forest Agency of Sardinia for the technical support provided at the experimental site, and the Department of Economics and Woody Plant Ecosystems (DESA) of the University of Sassari, which made available the use of the chemical laboratory. This research study was partially funded by the Italian Ministry of Education, University and Scientific Research (MIUR), Grant No. PON-13018.
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