Long-term interval burning alters fine root and mycorrhizal dynamics in a ponderosa pine forest

Journal Article · Sat Jan 01 04:00:00 EST 2005 · Journal of Applied Ecology

DOI:https://doi.org/10.1111/j.1365-2664.2005.01055.x· OSTI ID:937125

Hart, Stephen C ^[1]; Classen, Aimee T ^[2]; Robert, Wright J. ^[1]

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1. Northern Arizona University
2. ORNL

1. Plant roots and their mycorrhizal symbionts are critical components of forest eco- systems, being largely responsible for soil resource acquisition by plants and the main- tenance of soil structure, as well as influencing soil nutrient cycling. Silvicultural treatments should be guided by knowledge of how these below-ground components respond to different forest management practices. 2. We examined the cumulative effects of 20 years of prescribed burning at 2-year inter- vals. We measured fine root length density and fine root and mycorrhizal root biomass in the upper 15 cm of mineral soil in a south-western ponderosa pine forest over a com- plete burn cycle. 3. Repeated burning reduced fine root length, fine root biomass and mycorrhizal root biomass, as well as the amount of nitrogen and phosphorus stored in these below- ground pools. 4. Estimates of fine root production, fine root decomposition and nutrient dynamics were similar in burned and control plots. 5. Synthesis and applications . Although repeated-prescribed fire may be an effective, low-cost approach for reducing fuel loads and lessening the chance of a catastrophic wildfire in ponderosa pine forests, our results suggest that this strategy may negatively affect below-ground biomass pools and nutrient cycling processes in the long term. We recommend that mechanical reductions in fuel loads be conducted in these and similar forests that have not experienced fire for decades, before fire is reintroduced as a man- agement tool.

• Research Organization: Oak Ridge National Laboratory (ORNL)
• Sponsoring Organization: SC USDOE - Office of Science (SC)
• DOE Contract Number: AC05-00OR22725
• OSTI ID: 937125
• Journal Information: Journal of Applied Ecology, Journal Name: Journal of Applied Ecology Vol. 42; ISSN 0021-8901; ISSN JAPEAI
• Country of Publication: United States
• Language: English

Related Subjects

09 BIOMASS FUELS
Arizona
BIOMASS
ECOSYSTEMS
FORESTS
MAINTENANCE
MANAGEMENT
NITROGEN
NUTRIENTS
PHOSPHORUS
PINES
PRODUCTION
SOILS
SYNTHESIS
ecological restoration
ectomycorrhizae
fine roots
prescribed fire