69th SWCS International Annual Conference "Making Waves in Conservation: Our Life on Land and Its Impact on Water" July 27-30, 2014 Lombard, IL

1. Sediment source tracking in mid-west agricultural
basin 30 years after implementation of
conservation resource management
Tanja Williamson
Vicki Christensen
Bill Richardson
Jeff Frey
Allen Gellis
Kristen Kieta
Faith Fitzpatrick
July 23, 2014 SWCS
U.S. Department of the Interior
U.S. Geological Survey

2. WHY West Fork Beaver Creek?
Meanconcentration(mgL-1)
PercentageofRetiredLand
Low
High
Christensen V.G. and others.
2009. Water-quality and
biological characteristics and
responses to agricultural land
retirement in three streams of
the Minnesota River Basin, water
years 2006-08, U.S. Geological
Survey Scientific Investigations
Report 2009-5215. pp. 52.
http://pubs.usgs.gov/sir/2009/5215/

3. Hypotheses
1) Fine-grained sediment (<0.063 mm)
source would be discernible based on a
combination of stable isotopes and
elemental concentrations
- including land retired from agricultural
production 1-10 years before study began
2) Source contribution would vary in
association with land retirement

4. Study Design
Sediment Sources
Active Cropland (38)
Retired Cropland (17)
Streambanks (15)
Roads (5)

5. Study Design
control
control
buffered
mixed
wetland
NW SE
WFB
Fluvial Target Samples
Suspended Sediment (SS)
Channel Bed Sediment (B)
integrators

6. Do the fluvial targets differ?
NW SE WFB
Organic Carbon (mg g-1)
Median grain size (D50; mm)
p = 0.00059
60
30
0.006
0.003
SS – Suspended sediment
B – Channel bed sediment

7. Stable
Isotopes
Carbon
Forms
Macro-
elements Micro-elements
‰ mg g-1 mg g-1 mg kg-1
d13C CO3 C As In Sb
d15N Organic-C N Ba La Sc
C:N Al Be Li Sn
Ca Bi Mn Sr
Fe Cd Mo Th
K Ce Nb Tl
Mg Co Ni U
46 Na Cr P V
S Cu Pb W
Ti Ga Rb Y
Zn
Geochemical Fingerprint

8. Linear Discriminant Analysis
Gellis A.C., Noe G.B., Clune J.B., Myers M.K., Hupp C.R., Schenk E., Schwarz G. 2013.
Sources of Fine-Grained Sediment in Linganore Creek watershed, Maryland: 2008 to
2010, Scientific Investigations Report 2013-xxxx, U.S. Geological Survey.
Element Discriminant Tracer For Adjusted For
NW SE WFB D50 OC
Indium Y Y Y St, Cr, Rd Cr, Rd
Phosphorus Y Y Y St, Cr St, Cr, Ret
Total Carbon Y Y Y St, Cr
Beryllium Y St, Cr Cr
Thallium Y St, Cr, Ret Cr
Thorium Y Y St, Rd Cr, Ret
Titanium Y St St, Cr, Ret
NW SE
WFB
St – streambank Cr – cropland
Rd – road Ret – retired land

9. Separation of
Sediment
Sources
Suspended sediment
Channel bed sediment

10. Proportion of sediment
attributed to each source
Where more retired buffer:
• Lower % CROPLAND sediment
• Lower % STREAMBANK sediment
RETIRED LAND
• Present in channel bed
• NOT in suspended sediment
during high flow
SS – suspended
B – channel bed
CONTROL
BUFFERED
MIXED
INTEGRATOR
Road + Cropland + Retired Land + Streambank = 100%
SS – Suspended sediment
B – Channel bed sediment
c – control b – buffered
m – mixed i – integrator
* - significant difference SS vs. B
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11. Questions?
https://dl.sciencesocieties.org/publications/jeq/
abstracts/0/0/jeq2013.12.0521