INVESTIGADORES
DEFOSSE Guillermo Emilio
artículos
Título:
Effects of copetition in the postfire recovery of two bunchgrass species
Autor/es:
DEFOSSÉ, G. E. ; ROBBERECHT, R.
Revista:
JOURNAL OF RANGE MANAGEMENT
Editorial:
Society For Range Management
Referencias:
Lugar: Lakewood; Año: 1996 vol. 49 p. 137 - 142
ISSN:
0022-409X
Resumen:
The effects of competition on the postfire
recovery of Festuca idahoensis Elmer and Agropyron spicatum (Pursh) Scrib
& Smith was examined under natural conditions. Thirty plants of each species were exposed to
fire applied with a portable instrument system that allowed precise control of
fire temperature and duration, so that all plants received statistically
similar fire severity levels inside the meristematic crown region. Treated plants were subjected
to different levels of competition by periodically removing all or part of the
aerial biomass around a monitored bunchgrass plant. Soil water potential, soil temperatures and
plant productivity were determined at monthly intervals during the growing
season for the different competition treatments. No significant mortality due
to fire was observed for plants of either species. Although Festuca
did show meristematic tissue damage after the fire, regrowth that occurred within
15 days after the fire was more rapid than for Agropyron. Only Agropyron plants without competition reached
prefire productivity levels. Soil water potential was significantly more
negative in plots with competition.
Temperatures in the upper 10-cm of the soil profile were significantly
higher in plot with competition.
Competition reduced root production and also restricted aboveground
productivity by approximately 70% for Agropyron
and 115% for Festuca. The capacity of these species to survive fire
appears to be related more to the micro-environmental conditions created
following fire and to their capacity to compete for available soil water, than
to the direct effects of fire on plant tissues.