Changes in fire intensity have carry-over effects on plant responses after the next fire in southern California chaparral
Article first published online: 13 AUG 2012
© 2012 International Association for Vegetation Science
Journal of Vegetation Science
Volume 24, Issue 2, pages 395–404, March 2013
How to Cite
Moreno, J. M., Torres, I., Luna, B., Oechel, W. C., Keeley, J. E. (2013), Changes in fire intensity have carry-over effects on plant responses after the next fire in southern California chaparral. Journal of Vegetation Science, 24: 395–404. doi: 10.1111/j.1654-1103.2012.01466.x
- Issue published online: 24 JAN 2013
- Article first published online: 13 AUG 2012
- Manuscript Accepted: 15 JUL 2012
- Manuscript Received: 16 NOV 2011
- Spanish Ministry of Education and Science. Grant Number: AP 2003 – 1440
- FUME. Grant Number: ENV-2009-GA243888
- Adenostoma ;
- Ceanothus ;
- Fire cycle;
- Fire regime;
- Fire season;
- Fire severity;
- Post-fire recruitment;
Do variations in fire intensity within a stand determine changes in fire intensity and plant demographics in a subsequent fire?
San Diego (CA, USA); chaparral dominated by Adenostoma fasciculatum (resprouter) and Ceanothus greggii (seeder).
In 2003, a wildfire burned a young (16-yr-old) stand containing a set of experimental plots burned in 1987 with various levels of fire intensity. In 2004, all the 1987 plots were sampled for Adenostoma survival and the recruitment of both species. Similar measures were carried out in the adjacent old (75-yr) stand. Fire intensity in 2003 was estimated by a surrogate fire severity measure [minimum diameter of burned branches (branch diameter)].
In the young stand, branch diameter in 2003 was similar to the control plots in 1987, but lower than in the old stand. Fire intensity in 1987 did not significantly affect branch diameter in 2003. Survival of Adenostoma in the young stand was very low, much lower than after the 1987 burn and that in the old stand. Fire intensity in 1987 did not affect Adenostoma survival. Recruitment in Adenostoma increased, and in Ceanothus decreased, with increased fire intensity in 1987.
We demonstrate that there is a carry-over effect of fire intensity across a whole fire cycle on plant recruitment of the two dominant species. The 2003 fire partially reversed the relative effects on recruitment caused by elevated fire intensity in 1987. Arguably, this effect was driven by the contrasted relationships of the two species to fire intensity. Adenostoma survival in the young stand was much lower in 2003 than in 1987, despite similar branch diameter, and was also lower than in the old stand, despite higher branch diameter in this case. The causes of such mortality are unknown.