Soil Analysis Of ASoil Analysis Of A Volunteer Wetland Volunteer Wetland

Danette Miller

Advisors: Dr. Nairn and Dr. Strevett

University of Oklahoma

OverviewOverview

• Importance of substrate

• Field methods

• Laboratory methods

• Analysis

• Results

• Conclusions

SubstrateSubstrate

• Sink– Long term

retention of metals

• Types– Organic– Mineral

Problem StatementProblem Statement

• Is the substrate in the volunteer wetland a sink for soluble metals in the mine water discharge?

Study SiteStudy Site

Seep A

Seep B

Soil Sampling LocationsBaseline

T1

50N

Soil sampling

T3

00

T4

50

T6

00

T7

50

T1

50S

TW

M

Wetlands rock!

Field MethodsField Methods

• Sample collection– Auger, slide hammer,

manual extraction

• Replicates

• Sample storage

Laboratory MethodsLaboratory Methods

• pH• Moisture content• Particle density

– Pore space

• Bulk density• Total metals

– Microwave Digestion– AA spectrophotometer

ResultsResults

• pH– 6.08 to 7.56

• Moisture content– Surface: 55% to 86%– Subsurface: 25% to 42%

• Particle density– Surface: 0.26 to 0.56 g/cm3

– Subsurface: 0.27 to 0.57 g/cm3

ResultsResults

• Bulk Density– Surface: 0.3 to 0.6 g/cm3

– Subsurface: ND

• Total metals– Stratified trends

Results: Iron (Fe) TrendsResults: Iron (Fe) Trends

Stratified Iron Concentrations

0.0

200000.0

400000.0

600000.0

800000.0

1000000.0

1200000.0

Westmarsh

T-150 N T-150 S T-300 T-600 T-750

Location

Co

nc

en

tra

tio

n (

mg

/kg

)

Surface Subsurface

Results: Zinc (Zn) TrendsResults: Zinc (Zn) TrendsStratified Zinc Concentrations

0.0

10000.0

20000.0

30000.0

40000.0

50000.0

60000.0

70000.0

80000.0

Westmarsh

T-150N

T-150S

T-300T-600T-750

Location

Co

nc

en

tratio

n (m

g/k

g)

SurfaceSubsurface

ConclusionsConclusions

• Substrate is a sink

• Trends– Surface iron concentrations are elevated – Subsurface iron concentrations are similar to

background levels– Zinc trends were similar to iron trends

Future ResearchFuture Research

• Additional metals– Pb, Cd

• Available metals– metal concentration

available for biomassuptake

AcknowledgementsAcknowledgements

• NSF • Dr. Nairn and Dr. Strevett• REU lab research crew• Carrie Evenson and Jane Sund• Jacob Manko and Todd Wolfard • Erin Breetzke and Lisa Hare• Sharon and Janna Robbins• Wetland Willy