Present address: Department of Parasitology (SWEPAR), National Veterinary Institute and Swedish University of Agricultural Sciences, 751 89 Uppsala, Sweden.
Effects of inter-fire intervals on the reproductive output of resprouters and obligate seeders in the Proteaceae
Article first published online: 9 JUN 2005
Volume 30, Issue 4, pages 407–413, June 2005
How to Cite
KNOX, K. J. E. and MORRISON, D. A. (2005), Effects of inter-fire intervals on the reproductive output of resprouters and obligate seeders in the Proteaceae. Austral Ecology, 30: 407–413. doi: 10.1111/j.1442-9993.2005.01482.x
- Issue published online: 9 JUN 2005
- Article first published online: 9 JUN 2005
- Accepted for publication September 2004.
- fire ecology;
- fire frequency;
- obligate seeders;
Abstract Fire is often used as a management tool in fire-prone communities to reduce fuel loads with the intention of reducing the severity and extent of unplanned fires, often resulting in the increased occurrence of fire in the dry sclerophyll vegetation of Australia. This study examined the effects of fire frequency (length of the inter-fire interval) on the reproductive output of seven plant species in the Proteaceae, including obligate seeding shrubs (Hakea teretifolia, Petrophile pulchella), resprouting shrubs (Banksia spinulosa, Isopogon anemonifolius, Lambertia formosa) and resprouting trees (Banksia serrata, Xylomelum pyriforme). Reproductive output (measured as either number of confructescences or follicles) and relative size were estimated for 100 individuals at each of five sample sites, covering a range of past fire frequencies over 26 years including repeated short inter-fire intervals. Patterns in reproductive output (after standardizing for size) were related to the life-history attributes of the species. In areas that had experienced short inter-fire intervals, obligate seeders had greater reproductive output compared with longer intervals, and the reproductive output of resprouting shrubs was less. Fire frequency did not affect reproductive output of the resprouting trees. The decreased reproductive output of the resprouting shrubs could be due to the allocation of resources to regrowth following fire rather than to reproduction. It is less clear what process resulted in the increased reproductive output of obligate seeders in high fire frequency areas, but it could be due to the most recent fires being more patchy in the areas experiencing shorter inter-fire intervals, or it may have resulted from the selection for early reproduction in the high fire frequency areas. These results highlight the need to take into account past fire frequency at a site, in addition to time since the last fire, when planning prescribed fires.