Influence of hydrologic modifications on Fraxinus pennsylvanica in the Mississippi River Alluvial Valley, USA

Canadian Journal of Forest Research
By: , and 

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Abstract

We used tree-ring analysis to examine radial growth response of a common, moderately flood-tolerant species (<i>Fraxinus pennsylvanica</i> Marshall) to hydrologic and climatic variability for > 40 years before and after hydrologic modifications affecting two forest stands in the Mississippi River Alluvial Valley (USA): a stand without levees below dams and a stand within a ring levee. At the stand without levees below dams, spring flood stages decreased and overall growth increased after dam construction, which we attribute to a reduction in flood stress. At the stand within a ring levee, growth responded to the elimination of overbank flooding by shifting from being positively correlated with river stage to not being correlated with river stage. In general, growth in swales was positively correlated with river stage and Palmer Drought Severity Index (an index of soil moisture) for longer periods than flats. Growth decreased after levee construction, but swales were less impacted than flats likely because of differences in elevation and soils provide higher soil moisture. Results of this study indicate that broad-scale hydrologic processes differ in their effects on the flood regime, and the effects on growth of moderately flood-tolerant species such as <i>F. pennsylvanica</i> can be mediated by local-scale factors such as topographic position, which affects soil moisture.

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Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Influence of hydrologic modifications on Fraxinus pennsylvanica in the Mississippi River Alluvial Valley, USA
Series title Canadian Journal of Forest Research
DOI 10.1139/cjfr-2015-0138
Volume 45
Issue 10
Year Published 2015
Language English
Publisher NRC Research Press
Contributing office(s) Coop Res Unit Atlanta
Description 10 p.
First page 1397
Last page 1406
Country United States
Other Geospatial Bayou Cocodrie National Wildlife Refuge, White River National Wildlife Refuge
Online Only (Y/N) N
Additional Online Files (Y/N) N