The dendroclimatic signal of Quercus alba in the Blue Ridge Ecoregion near Brevard, NC.
Start Date
12-4-2024 2:15 PM
Location
CLC Ballroom
Document Type
Presentation
Abstract
White oak (Quercus alba) is a well-known proxy for the effects of changing climates using the science of dendroclimatology, which was established in the 1920’s with the observation that tree ring growth patterns are affected by yearly differences in moisture and temperature in the areas in which the trees are growing. The degree to which a specific tree species responds to local climates can vary in relation to the tolerances that a tree will have to moisture availability, but some trees are more sensitive to others and will produce growth rings that more closely reflect these abiotic factors vs. others. White oak is an excellent tree with respect to sensitivity to moisture availability by producing narrow rings during dry years and broader rings during wet years. Several research projects at Presbyterian College have already established white oak’s reliability in the Piedmont region of South Carolina, but similar studies of white oak have not been accomplished in higher elevation environments at the edge of white oaks natural environment. This study looked at the dendroclimatic signal of white oak from the Blue Ridge ecoregion of North Carolina, in a wooded forest near Brevard, NC. Standard dendrochronology techniques were utilized to extract cores from white oaks living in a varied topographic setting, which was also considered to be a variable of interest given the effects of water availability for trees living on a slope. Cores were taken to the lab and prepared for examination using a microscope and a Velmex computerized measuring system. Core widths were then compared to the Palmer Drought Severity Index (PDSI) which is a measure of water availability and has a historical record back to the early 1900’s. The results from the trees sampled showed that white oak has a variable signal. During certain years, tree rings and the PDSI were very highly correlated (r=.93). During other growth segments, tree rings were well below acceptable correlation levels when compared to the PDSI. The particular area in which the trees were growing has a highly variable topographic profile, and this area in particular is also known to have a much higher rainfall rate than the NOAA moisture collecting site near Asheville NC. It may also be possible that the growth pattern for white oak is variable for other reasons that are not tied directly to the availability of moisture.
Keywords
Quercus alba, dendroclimatology, Blue Ridge, abiotic factors
The dendroclimatic signal of Quercus alba in the Blue Ridge Ecoregion near Brevard, NC.
CLC Ballroom
White oak (Quercus alba) is a well-known proxy for the effects of changing climates using the science of dendroclimatology, which was established in the 1920’s with the observation that tree ring growth patterns are affected by yearly differences in moisture and temperature in the areas in which the trees are growing. The degree to which a specific tree species responds to local climates can vary in relation to the tolerances that a tree will have to moisture availability, but some trees are more sensitive to others and will produce growth rings that more closely reflect these abiotic factors vs. others. White oak is an excellent tree with respect to sensitivity to moisture availability by producing narrow rings during dry years and broader rings during wet years. Several research projects at Presbyterian College have already established white oak’s reliability in the Piedmont region of South Carolina, but similar studies of white oak have not been accomplished in higher elevation environments at the edge of white oaks natural environment. This study looked at the dendroclimatic signal of white oak from the Blue Ridge ecoregion of North Carolina, in a wooded forest near Brevard, NC. Standard dendrochronology techniques were utilized to extract cores from white oaks living in a varied topographic setting, which was also considered to be a variable of interest given the effects of water availability for trees living on a slope. Cores were taken to the lab and prepared for examination using a microscope and a Velmex computerized measuring system. Core widths were then compared to the Palmer Drought Severity Index (PDSI) which is a measure of water availability and has a historical record back to the early 1900’s. The results from the trees sampled showed that white oak has a variable signal. During certain years, tree rings and the PDSI were very highly correlated (r=.93). During other growth segments, tree rings were well below acceptable correlation levels when compared to the PDSI. The particular area in which the trees were growing has a highly variable topographic profile, and this area in particular is also known to have a much higher rainfall rate than the NOAA moisture collecting site near Asheville NC. It may also be possible that the growth pattern for white oak is variable for other reasons that are not tied directly to the availability of moisture.