The Shift of Plant Characteristics in Response to a Complex Disturbance in Temperate Deciduous Forest.
Mentor 1
Stefan Schnitzer
Location
Union Wisconsin Room
Start Date
24-4-2015 10:30 AM
End Date
24-4-2015 11:45 AM
Description
Humans have caused massive compositional shifts of plant species in eastern deciduous forests by altering historic disturbance patterns. Long-term fire suppression and clear-cutting have altered light availability in the understory, which affects many understory plant species. Additionally, the elimination of top predator species has resulted in an overabundance of herbivores such as white tailed deer. These factors may be altering the way in which plants interact with each other as well as their environment. Plant functional traits may provide insights into how plants shift strategies to adapt to changing conditions. To understand how plants adapt to complex changes in eastern deciduous forests, we measured four key plant leaf traits that are important to temperate forest plants (specific leaf area, leaf toughness, leaf ignitibility, and leaf thickness). We examined 10 understory species within the context of a fully factorial experimental manipulation of controlled burns, canopy gap formation, and fences that excluded large terrestrial herbivores (mainly deer) in 64 plots in northwestern West Virginia. We found that when plants are exposed to a combination of fire and deer browsing they had significantly thicker leaves (p=0.021, t-statistic=2.303, df=1269). Leaves were significantly tougher when deer are experimentally removed (both in forest burns and when canopy gaps were added; p<0.05 for all fenced treatments). When plants were exposed to fire regularly every 10 years, the amount of time it takes for leaves to ignite increased significantly when deer were removed (p=0.0002, t =3.714, df=1269 and p=0.0328, t =2.137, df=1269). These findings suggest that deer alter plant leaf construction and thus their overabundance may have important ramifications for plant functional strategies in eastern deciduous forests.
The Shift of Plant Characteristics in Response to a Complex Disturbance in Temperate Deciduous Forest.
Union Wisconsin Room
Humans have caused massive compositional shifts of plant species in eastern deciduous forests by altering historic disturbance patterns. Long-term fire suppression and clear-cutting have altered light availability in the understory, which affects many understory plant species. Additionally, the elimination of top predator species has resulted in an overabundance of herbivores such as white tailed deer. These factors may be altering the way in which plants interact with each other as well as their environment. Plant functional traits may provide insights into how plants shift strategies to adapt to changing conditions. To understand how plants adapt to complex changes in eastern deciduous forests, we measured four key plant leaf traits that are important to temperate forest plants (specific leaf area, leaf toughness, leaf ignitibility, and leaf thickness). We examined 10 understory species within the context of a fully factorial experimental manipulation of controlled burns, canopy gap formation, and fences that excluded large terrestrial herbivores (mainly deer) in 64 plots in northwestern West Virginia. We found that when plants are exposed to a combination of fire and deer browsing they had significantly thicker leaves (p=0.021, t-statistic=2.303, df=1269). Leaves were significantly tougher when deer are experimentally removed (both in forest burns and when canopy gaps were added; p<0.05 for all fenced treatments). When plants were exposed to fire regularly every 10 years, the amount of time it takes for leaves to ignite increased significantly when deer were removed (p=0.0002, t =3.714, df=1269 and p=0.0328, t =2.137, df=1269). These findings suggest that deer alter plant leaf construction and thus their overabundance may have important ramifications for plant functional strategies in eastern deciduous forests.
