Editing Floodplain (section)

=== Oxygen in floodplain soils ===
Floodplain soil composition is unique and varies widely based on microtopography. Floodplain forests have high topographic heterogeneity which creates variation in localized hydrologic conditions.<ref>{{Cite journal |last1=De Jager |first1=Nathan R. |last2=Thomsen |first2=Meredith |last3=Yin |first3=Yao |date=April 2012 |title=Threshold effects of flood duration on the vegetation and soils of the Upper Mississippi River floodplain, USA |url=https://doi.org/10.1016/j.foreco.2012.01.023 |journal=Forest Ecology and Management |volume=270 |pages=135–146 |doi=10.1016/j.foreco.2012.01.023 |issn=0378-1127}}</ref> Soil moisture within the upper 30 cm of the soil profile also varies widely based on microtopography, which affects oxygen availability.<ref>{{Cite journal |last=Krumbach |first=A. W. |date=October 1959 |title=Effects of microrelief on distribution of soil moisture and bulk density |url=http://doi.wiley.com/10.1029/JZ064i010p01587 |journal=Journal of Geophysical Research |volume=64 |issue=10 |pages=1587–1590 |doi=10.1029/JZ064i010p01587|bibcode=1959JGR....64.1587K }}</ref><ref>{{Cite journal |last1=Hupp |first1=Cliff R. |last2=Osterkamp |first2=W. R. |date=June 1985 |title=Bottomland Vegetation Distribution along Passage Creek, Virginia, in Relation to Fluvial Landforms |url=https://esajournals.onlinelibrary.wiley.com/doi/10.2307/1940528 |journal=Ecology |volume=66 |issue=3 |pages=670–681 |doi=10.2307/1940528 |jstor=1940528 |bibcode=1985Ecol...66..670H |issn=0012-9658}}</ref> Floodplain soil stays aerated for long periods in between flooding events, but during flooding, saturated soil can become oxygen-depleted if it stands stagnant for long enough. More soil oxygen is available at higher elevations farther from the river. Floodplain forests generally experience alternating periods of aerobic and anaerobic soil microbe activity, affecting fine root development and desiccation.<ref>{{Cite journal |last=Keeley |first=Jon E. |date=March 1979 |title=Population Differentiation along a Flood Frequency Gradient: Physiological Adaptations to Flooding in Nyssa sylvatica |url=https://esajournals.onlinelibrary.wiley.com/doi/10.2307/1942574 |journal=Ecological Monographs |volume=49 |issue=1 |pages=89–108 |doi=10.2307/1942574 |jstor=1942574 |bibcode=1979EcoM...49...89K |issn=0012-9615}}</ref><ref>{{Citation |last=Kozlowski  |first=T.T. |title=Extent, Causes, and Impacts of Flooding |date=1984 |work=Flooding and Plant Growth |pages=1–7 |url=https://doi.org/10.1016/b978-0-12-424120-6.50006-7 |access-date=2024-04-20 |publisher=Elsevier |doi=10.1016/b978-0-12-424120-6.50006-7|isbn=978-0-12-424120-6 }}</ref><ref>{{Cite journal |last1=Jones |first1=Robert H. |last2=Lockaby |first2=B. Graeme |last3=Somers |first3=Greg L. |date=1996 |title=Effects of Microtopography and Disturbance on Fine-Root Dynamics in Wetland Forests of Low-Order Stream Floodplains |url=https://www.jstor.org/stable/2426631 |journal=The American Midland Naturalist |volume=136 |issue=1 |pages=57–71 |doi=10.2307/2426631 |jstor=2426631 |issn=0003-0031}}</ref>