Thesis Title

Savanna Restoration Through Prescribed Fire: Demographic and Physiological Responses of Oak and Hickory Seedlings and Saplings to a Changing Light Environment

Date of Graduation

Summer 2004

Degree

Master of Science in Biology

Department

Biology

Committee Chair

Alexander Wait

Keywords

prescribed fire, canopy coverage, savanna restoration, demography, gas-exchange, Quercus spp., light availability

Subject Categories

Biology

Abstract

Prescribed fire is a common tool for restoring and maintaining degraded oak savannas in the Midwest. Long-term success of restoration and maintenance ultimately depends upon new individuals entering the canopy. However, little is known about seedling and sapling response to this periodic disturbance. This study identifies how fire affects community structure and composition of dominant savanna seedlings and saplings, and takes the novel approach of linking conceptually and empirically demographic responses of seedlings and saplings to growth and gas exchange. This study was conducted within the Drury Conservation Area, located in Taney County, Missouri where there is both historical presence of oak savannas, and varying fire histories. Study sites representing unburned closed forest (N=2) and recently burned closed forest (n=2) were established in 2001. Twelve belt transects with an average area of 102m² were established and sampled to determine indirect links between fire history effects on canopy leaf production and the demography and physiology of seedlings and samplings (Quercus spp., Carya spp., Juniperus spp.). Following prescribed burns, canopy light penetration was significantly greater in burned forest sites than in unburned forest sites. Density, basal area, mortality, and recruitment appear to be increasing in burned forest sites relative to unburned forest sites. Maximum and ambient net photosynthetic rates increased between habitats as light availability increased. Data suggest that current prescribed fire regimes are positively affecting white oak regeneration in previously closed forests, while effectively removing cedar seedlings.

Copyright

© Douglas P. Aubrey

Citation-only

Dissertation/Thesis

Share

COinS