redoximorphic features and hydric soils nc state university department of soil science nc state...
TRANSCRIPT
Redoximorphic Features Redoximorphic Features and Hydric Soilsand Hydric Soils
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
Redoximorphic Features Formed by changes in redox conditions in
saturated soil Reduction and oxidation of C, Fe, Mn, and
S compounds Translocation of C, Fe, Mn, and S
compounds
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
Redox TransformationsCoating of Fe2O3
Remove Fe
Brown Soil Fe3+
Fe2+
Gray Soil
2e- + 6H+ + Fe2O3 2Fe(II) + 3H2ONC STATENC STATE UNIVERSITY UNIVERSITY
DEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCENC STATENC STATE UNIVERSITY UNIVERSITY
DEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCENC STATENC STATE UNIVERSITY UNIVERSITY
DEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCENC STATENC STATE UNIVERSITY UNIVERSITY
DEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
Redox features are like M&Ms
=
In order to form features:
• must have anaerobic conditions (reduced and saturated)
• must have Fe and/or Mn (electron acceptor)
• must have microbes (bugs)
• must have carbon (food for the bugs)
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
Redoximorphic Features
• Redox concentrations – zone where Fe - Mn oxides have accumulated
• Redox depletions – zone where of Fe – Mn oxide have been stripped out
• Reduced matrix – low chroma matrix that changes color when exposed to air
Redox depletions (Fe depletions)
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
Fe depletionsFe depletion on ped face
Fe depletion on pore
Fe depletion in ped interior
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
Fe depletions
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
Concentrations and depletionsConcentrations and depletions
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
Redox concentrations (Fe masses, Fe pore linings)
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
Fe masses and Fe pore linings
Pore lining on root channel
Pore lining on Ped surface
Nodule
Fe massin matrix
Concretion
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
Fe pore linings
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
Fe masses
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
Reduction, oxidation and Reduction, oxidation and translocation = saturationtranslocation = saturation
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
1. Plant root grows into 1. Plant root grows into soilsoil2. Root dies and starts 2. Root dies and starts to decomposeto decompose
3. Water table rises3. Water table rises
4. Bacteria continue 4. Bacteria continue to decompose rootto decompose root
Oxygen reducedOxygen reduced
Nitrate reducedNitrate reduced
Fe reduced and Fe reduced and removed, soil turnsremoved, soil turns graygray
5. Reduced Fe moves 5. Reduced Fe moves away from decomposing away from decomposing rootroot
Reduced Fe oxidizes, Reduced Fe oxidizes, soil turnssoil turns redred
7. Root completely 7. Root completely decomposeddecomposed
6. Water drains from 6. Water drains from root channelroot channel
8. Water table drops8. Water table drops
Redox depletionRedox depletion
Redox Concentration Redox Concentration (Pore lining)(Pore lining)
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
NC STATENC STATE UNIVERSITY UNIVERSITYDEPARTMENT of DEPARTMENT of SOIL SCIENCESOIL SCIENCE
Lithochromic mottle
Redox depletion
Concepts of Wetlands, Hydric Soils, and
Wetland Hydrology
What is a wetland?
Wetland Definition (as defined by FSA Manual and
COE 1987 Manual)
• has wetland hydrology
• has a predominance of hydrophytic vegetation
• the presence of hydric soil
Wetland hydrology occurs when:
• the water table is at or near the surface (12 inches) and,
• present for at least 5 percent (consecutive) of the growing season.
0
6
12
18
24
30
36
42
48
1 2 3 4 5 6 7 8 9 10 11 12
Month
Dep
th (
in.)
Determining Wetland Hydrology
Determining the Growing Season
• Use NRCS County Soil Survey for beginning and end dates
• Determine number of days in season
• Multiply by 0.05
• Usually between 12 and 14 days in this region
Definition of Hydric Soil
A hydric soil is a soil that formed under conditions of saturation,
flooding, or ponding long enough during the growing season to
develop anaerobic conditions in the upper part
Field Indicators of Hydric Soils
Field indicators of hydric soils are designed for on-site identification of
hydric soils
Field Indicators of Hydric Soils in the United States
Version 5.01