Date of Award
1-1-2025
Document Type
Thesis
Degree Name
M.S. in Biological Science
First Advisor
John S. Brewer
Second Advisor
Jason D. Hoeksema
Third Advisor
Peter C. Zee
School
University of Mississippi
Relational Format
dissertation/thesis
Abstract
Fire restoration to systems with a history of fire suppression (e.g., eastern deciduous forests) often leads to increases in herbaceous groundcover plant community diversity and density. Precisely how fire interacts with community assembly processes to form species-rich post-fire communities is poorly understood. This study examined the effects of restoration stage (older and more recent) and burn/herbicide treatments to better understand the mechanisms (e.g., seedling recruitment) and assembly processes (niche-based vs. neutral) that determine post-fire plant assemblages in a mesophied upland oak-hickory forest in north-central Mississippi (USA). 21 1-m2 sampling plots were established in each of four 1-ha blocks with varying stages of fire restoration (thinning + repeated burning). Each sampling plot was randomly assigned a treatment (burning, burn + pre-emergent herbicide application, control) in a balanced design. Composition surveys were conducted every year from 2022-2024 to determine how restoration stage and treatments influence legume species richness, abundance and composition. Mature plant leaf and growth traits were also measured to examine the effects of fire on functional trait dispersion and thus the potential for niche partitioning. From 2022 to 2024, the block with the longest history of fire restoration had the greatest increases in legume species richness and abundance. The immediate effects of burning were most evident at later stages of restoration. Legume species composition was significantly different in the latest stage of restoration compared to all other stages. When examining trait responses using community-weighted trait means, fire restoration appeared to favor species with low leaf area; however, a null model analysis revealed that trait responses to restoration using community-weighted trait means were misleading due to a weak relationship between trait expression and species composition. Long-term restoration was associated with increased functional dispersion, but results of a null model analysis suggested that restoration increased functional dispersion indirectly by increasing species density. Results of the short-term fire restoration experiment revealed that fire-stimulated seedling emergence could play an important role in post-fire recruitment strategies. Results support other research indicating that fire restoration increases understory plant diversity, but we found no evidence of niche-based selection determining composition.
Recommended Citation
Jewess, Madeline G., "Linkages Between Functional Traits and Legume Species Composition and Diversity During Restoration of a Fire-Maintained Oak Woodland" (2025). Electronic Theses and Dissertations. 3301.
https://egrove.olemiss.edu/etd/3301