Stand restoration burning in oak–pine forests in the southern Appalachians: effects on aboveground biomass and carbon and nitrogen cycling

• Published in: Forest ecology and management Vol. 190; no. 2; pp. 311 - 321
• Main Authors: Hubbard, Robert M, Vose, James M, Clinton, Barton D, Elliott, Katherine J, Knoepp, Jennifer D
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 22-03-2004; Elsevier
• Subjects: Animal and plant ecology; Animal, plant and microbial ecology; biogeochemical cycles; Biological and medical sciences; biomass; carbon dioxide; carbon sequestration; Coarse woody debris; dead wood; fermentation; forest litter; forest regeneration; forest soils; forest stands; Forestry; Fundamental and applied biological sciences. Psychology; General forest ecology; Generalities. Production, biomass. Quality of wood and forest products. General forest ecology; Kalmia latifolia; Litter; mineralization; mixed forests; nitrogen; overstory; Oxydendrum arboreum; Pinus; Pinus strobus; Pinus virginiana; prescribed burning; Prescribed fire; Quercus; Quercus alba; Quercus coccinea; Quercus falcata; Quercus montana; Soil CO 2; soil organic matter; soil temperature; soil water content; Synecology; Terrestrial ecosystems; understory; watersheds; Appalachian region; Tennessee; Georgia; Appalachians; North America; America; USA, Appalachian Mts; Soil CO 2; Litter; Prescribed fire; Coarse woody debris; Burned ground; Carbon cycle; Forests; Nitrogen cycle; Understory; Watershed; Carbon dioxide
• ISSN: 0378-1127; 1872-7042
• DOI: 10.1016/j.foreco.2003.10.021

Understory prescribed burning is being suggested as a viable management tool for restoring degraded oak–pine forest communities in the southern Appalachians yet information is lacking on how this will affect ecosystem processes. Our objectives in this study were to evaluate the watershed scale effects of understory burning on total aboveground biomass, and the carbon and nitrogen pools in coarse woody debris (CWD), forest floor and soils. We also evaluated the effects of burning on three key biogeochemical fluxes; litterfall, soil CO
2 flux and soil net nitrogen mineralization. We found burning significantly reduced understory biomass as well as the carbon and nitrogen pools in CWD, small wood and litter. There was no significant loss of carbon and nitrogen from the fermentation, humus and soil layer probably as the result of low fire intensity. Burning resulted in a total net loss of 55
kg
ha
−1 nitrogen from the wood and litter layers, which should be easily replaced by future atmospheric deposition. We found a small reduction in soil CO
2 flux immediately following the burn but litterfall and net nitrogen mineralization were not significantly different from controls throughout the growing season following the burn. Overall, the effects of burning on the ecosystem processes we measured were small, suggesting that prescribed burning may be an effective management tool for restoring oak–pine ecosystems in the southern Appalachians.