Reconciling Podzolic and Redoximorphic Responses to Seasonal Saturation Willie Harris, Rex Ellis, Wade Hurt, Chumki Banik, Scarlett Balboa, Travis Richardson, Chad Rischar, Ashley Phillips Acknowledgments: We thank Mr. Kafui Awuma and Ms. Kimberly Johnson for assistance with various field and laboratory aspects of this project. We also thank the following students for their help in the field with well installation, surveying, photography, etc.: Jeff Brantley, Luke Gommermann, Will Mahler, and Alexandra Rozin. Funding from USDA-NRCS and McIntire-Stennis

“Podzolic” relates to … Podzolization Pedogenic translocation & joint accumulation of C & metals Produces Bh horizon in FL Well expressed Bh = Spodic horizon & Spodosol soil order Eluviation – loss Illuviation – gain A E Bh Florida Spodosol

Spodosol distribution worldwide Mainly restricted to imperfectly-drained sites Commonly well drained Randy Schaetzl What is the role of the water table (WT) in fostering Spodosol formation in Florida?

“Seasonal High Water Saturation” (SHS) SHS commonly about here E Bh Florida Spodosol

“Redoximorphic” relates to … Redoximorphic features: Features associated with wetness – SHS indicators Result from alternating periods of reduction & oxidation of Fe & Mn in soils Concentrations Depletions Images from page 18 of "Field Indicators of Hydric Soils" ftp://ftp-fc.sc.egov.usda.gov/NSSC/Hydric_Soils/FieldIndicators_v7.pdf

Main Objectives Address uncertainties of redoximorphic–podzolic morphological effects along hydrologic gradients Test idea that Fe depletion along hydrologic gradients is a factor explaining association of Florida Spodosols with fluctuating WT

Approach Evaluate hydropedological trends along sandhill-flatwood-wetland transitions Install wells along 4 transects (23 total) Have local experts make SHS calls Monitor WT over a 2-year period Described and sample soils at each well site Determine Al, Fe, and C distribution by horizon

Transect Site Locations – Alachua Co. Austin Carey Memorial Forest (ACMF) – 2 sites 20 km Longleaf Flatwoods Reserve (LFR) – 2 sites 12.4 miles

Transect Site Plant Community Transition Example:“sandhills” to flatwoods @ site 3 Marginal “sandhills” Flatwoods bordering wetland

Oh, yeah! Come over here and say that! What are we “reconciling”? … Bunk! That’s not redox! Oh, yeah! Come over here and say that!

What are we “reconciling”? … (cont.) Overlapping morphological effects of both processes along transition from Spodosols to better-drained soils Evidence of process linkage through redox influence on Fe Jeff Locuta’s image – Pedology class 2012

What are we “reconciling”? … (cont.) Schematic cross section of transition Soils shown were along transition Note trend in water table and degree of podzolization Note “cross-over” between SHS and Bh How are SHS indicators (redox features) affected by Bh? A “Sandhills” “Flatwoods”

A. WT & SHS indicator correspondence Findings A. WT & SHS indicator correspondence

SHS calls vs. WT Late summer Water in all wells Water table fluctuating

Transect 1 - LFR Concentrations Depletions (aka “stripping”)

Conclusions –WT & SHS calls Strong relation between SHS & mean WT depth during periods of fluctuation Highest WT shallower than SHS calls, especially on wettest end Predominant indicator was depletion Depletions were indicators for SHS calls in Bh

Thanks! Questions?