<p> Hydrologic connectivity in the Atchafalaya River Basin has been dominated by anthropogenic structures for the past 50+ years. To better understand how these structures have affected the Basin, two techniques were used to assess the hydrologic connectivity within tracts of land near Bayou Sorrel. The first technique used historical and current aerial imagery to create a canopy change map in ArcMap 10.3. Three classifications—full canopy, partial canopy, and open water—were used for the analysis. The canopy change map showed that from 1957 to 1998, “full canopy” decreased by 18%, “open water” increased by 4%, and “partial canopy” increased by 26%. The second technique used tree-ring width and ring-to-ring carbon isotope measurements on seven bald cypress trees (<i>Taxodium distichum </i>) to test whether or not evolution of a regional distributary channel has a measurable effect on tree growth. Neither the carbon isotope data nor the tree-ring widths correlated with channel evolution, but tree-ring width did correlate with monthly temperature during the growing season, suggesting an overarching climate signal on tree-ring growth at this site. Frequent flooding at the site may be responsible for the lack of any correlation between tree-ring carbon isotope measurements and channel evolution or climate; however, additional work to test the effect of flooding on tree stress is needed. I conclude that canopy change maps can be a useful tool for assessing changing hydrology within the Atchafalaya River Basin.</p><p>
| Identifer | oai:union.ndltd.org:PROQUEST/oai:pqdtoai.proquest.com:10608445 |
| Date | 08 May 2018 |
| Creators | Valentine, Leslie A. |
| Publisher | University of Louisiana at Lafayette |
| Source Sets | ProQuest.com |
| Language | English |
| Detected Language | English |
| Type | thesis |
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