Effect of a postfire environment on the establishment of Prosopis caldenia seedlings in central semiarid Argentina

• Published in: Austral ecology 2007-08, Vol.32 (5), p.581-591
• Main Authors: De VILLALOBOS, ANA E, PELÁEZ, DANIEL V, BÓO, ROBERTO M, MAYOR, MIRTA D, ELIA, OMAR R
• Format: Article
• Language: English
• Subjects: Arid zones; early growth; emergence; Forest & brush fires; mortality; Plant populations; postfire conditions; Prosopis caldenia; Soils; survival; Survival analysis; woody encroachment
• ISSN: 1442-9985; 1442-9993
• DOI: 10.1111/j.1442-9993.2007.01731.x

The objective of this work was to evaluate postfire environmental effects on the emergence, survival and growth of Prosopis caldenia seedlings in relation to different controlled fire frequencies, seed scarification methods, and planting site. Seedling emergence was significantly higher in experimental units exposed twice and three times to controlled fire than in unburned experimental units. The highest average seedling survival was recorded with triple exposure to controlled fires. Emergence, survival and growth of seedlings from seeds exposed to acid scarification and 600°C for 5 min were higher in the burned experimental units than in the unburned ones. In the former, seedling survival was higher beneath a P. caldenia canopy than in an adjacent open site, though seedling emergence was similar in both planting sites. Our results suggest that postfire conditions characterized by a reduction in the vegetative cover and competition interference and an increase in soil temperatures and nutrients levels (e.g. nitrogen and phosphorus) may facilitate the establishment of P. caldenia seedlings in the Caldenal.