Transcript Poster2008.ppt

Effects of Development on the Big Darby Creek Watershed: Stream Geochemistry
Catherine Maxwell, School of Earth Sciences, The Ohio State University, Columbus, Ohio, 43210-1398
W. Berry Lyons, Byrd Polar Research Center, The Ohio State University, Columbus, Ohio, 43210
1. Introduction
3. Long-Term Time Series Data
5. Discussion
The Big Darby Creek is categorized as a
national scenic river with an array of biological
species. Since this is one of the last pristine
rivers in Ohio, concern has grown in regards
to human disturbances to the system. Its
watershed has been mainly used for
agricultural purposes since early pioneers
settled the area. Recently, the outskirts of
Columbus have been expanding westward
into the watershed. Changes in the land use
from rural to suburban should leave an
impression on the chemistry of the stream
water. Long-term stream chemistry analysis
will show the effect of human activities on the
Big Darby Creek.
•Cl- concentrations in the Little Darby are in the 400 M range in the late 1960s and early 1970s, then in
the 1980s concentrations drastically increase to between 705 M and 1128 M, then remain close to
those high values throughout the rest of the study.
•Concentrations of anions in the Darby are similar to other Ohio Rivers that are influenced by agriculture
such as the Scioto River. NO3- in the stream water is probably from agricultural sources.
2. Methods and Analysis
•Seasonal trends are apparent and are related to human activities and flow variations.
•Cl- concentrations in the Big Darby are between 564 M and 874 M in the late 1960s. The
concentrations increase to over 1000 M by 1992 and drastically increase in 2007 up to the highest
concentration of 2274 M.
•Increase in SO42- over time.
•Increase in Cl- since the 1970s.
•F- m concentrations in the Little Darby stay relatively constant throughout all historical data.
•NO3- relatively constant, but the seasonal variability is greater than the long term variability.
•NO3- concentrations reached a maximum in October of 1965 and have since remained under half of that
concentration, in the Big Darby Creek. In the Little Darby Creek, NO3- concentrations reached a
minimum of 3 M in September of 2000 and a maximum of 815 M in April of 2001.
•Many different human activities can contribute Cl- and SO42- to aquatic systems, therefore they are
good indications either of general human disturbance in the watershed or of population density.
•SO42- concentrations are between 5 M and 97 M in the 1980s, then increase to between 335 M and
815 M in 2000-2001. In 2007 the concentrations remain between 348 M and 590 M.
•Kaushal et al. (2005) have demonstrated that Cl- concentrations have been increasing at high rates in
northeast USA streams due to de-icing operations. The application of de-icing salt Cl- in Ohio averages
about 310 X 103 M km-2 yr-1(Jackson and Jobbagy, 2005). Gardner and Carey (2004) have
demonstrated that in Columbus, winter additions of road salt onto highways are observed influencing Clconcentrations in the Olentangy River throughout the calendar year.
•Samples collected every two weeks at the
Big Darby Creek, and a tributary, the Little
Darby (Figure 1)
•Filtered through 0.4m Nuclepore membrane
filters using prewashed plastic filtration towers
Anions in Big Darby Creek, Darbydale, Ohio
Cl, µM
•Relative standard deviation for F-, Cl-, NO3-,
and SO42- were 5%, 2%, 2%, and 1%,
respectively
N-NO3, µM
F, µM
2500
2500.0
2000
2000.0
Concentration (µM)
Concentration (µM)
•Analyzed for major anions using the ion
chromatograph(IC)
1500
1000
500
Cl, µM
03-1967
09-1972
03-1978
0.0
02-2003
04-2003
06-2003
N-NO3, µM
Values of Anions in Little Darby, West Jefferson,
Ohio
SO4, µM
F, µM
1100
N-NO3, µM
F, µM
SO4, µM
900
400
300
900
800
700
600
500
400
300
800
600
500
300
200
100
100
100
12-1975
06-1981
11-1986
05-1992
07-1996
09-1996
Time
10-1996
12-1996
02-1997
03-1997
Time
•Look for more historic chemical data
400
200
06-1970
6. Future Goals
700
200
0
05-1996
SO4, µM
•Kelly et al. (2008) have observed an annual increase of about 40 M L-1 in chloride in rural streams in
southeast New York state between 1985-2005 (from about ~340 M to 1125 M L-1 ). These authors
estimate that 83% of this increase is due to road de-icing salt.
1000
Concentration (µM)
500
N-NO3, µM
•For comparison in the Scioto River, the Cl- concentrations range from 577 to 2410 M L-1 with the
highest concentrations observed in the late summer and the lowest in the spring (Carey and Lyons,
unpublished). Nitrate concentrations in the Scioto range from 19-474 M L-1 with the lowest
concentrations in the late summer and the highest in the late winter/spring period (Carey and Lyons,
unpublished).
1100
900
600
Cl, µM
• Photographs were
taken by Sarah Fortner
•Nowhere in the Darby system, however, does the concentration reach 7000 M L-1, the recommended
upper limit for the protection of freshwater life.
1200
1000
Concentration (µM)
Concentration (uM)
Cl, µM
1100
1000
700
09-2003
Values of Anions in Little Darby, West Jefferson, Ohio
1200
800
07-2003
Time
1200
0
12-1964
•Below is the view
downstream of the Big
Darby Creek in
Darbydale
1000.0
08-1983
Values of Anions in Little Darby, West Jefferson, Ohio
Cl, µM
•Above is the
downstream view of
Little Darby Creek in
West Jefferson
SO4, µM
1500.0
Time
F, µM
N-NO3, µM
500.0
0
09-1961
Figure 1
Pictures
Anions in Big Darby Creek, Darbydale, Ohio
0
02-2003
04-2003
06-2003
07-2003
09-2003
•Determine SO42- sources
Time
•Gather discharge rate data
•Retrieve population data from census records
4. Seasonal Variation from 2007
Acknowledgements
•F- concentrations are the lowest of all anions, ranging from 16.8 M to 31.6 M
in the Little Darby and 17.3 M to 30.9 M in the Big Darby.
Thank you to Sarah Fortner, Chris
Gardner, Kathy Welch, and Rebecca
Witherow.
•NO3- concentration decreases from 289 M to 9 M in the spring to the summer
and then increases to 265 M in autumn in the Big Darby river. In the Little
Darby Creek NO3- concentrations decrease from 314 M to 10 M.
•SO42- increases steadily from 365 M to 590 M in the Little Darby, and from
374 M to1063 M in the Big Darby.
•Cl- concentrations increase overall in the Big Darby Creek from 772 M to 2274
M. In the Little Darby they fluctuate between 671 M and 819 M.
•Calculate area of pavement in watershed
•Collect data of salt application volume
References
Big Darby Creek Land Use. Ohio EPA Division of Surface Water. http://www.epa.state.oh.us/dsw/permits/GP_ConstructionSiteStormWater_Darby.html, accessed 2 May 2008.
Gardner, C. B. and Carey, A. E., Trace Metal and Major Ion Inputs into the Olentangy River from an Urban Storm Sewer. Environ. Sci. Technol. 2004, 38, 5319-5326.
Jackson, R. B. and Jobbagy, E. G., 2005 From icy roads to salty streams, Proceedings of the National Academy of Sciences, 102, 12, 487-14, 488.
Kaushal, S. S. et al., Increased salinization of freshwater in the northeastern United States, Proceedings of the National Academy of Sciences, 102, 13, 517-13, 520.
Kelly, V. R. et al., Long-Term Sodium Chloride Retention in a Rural Watershed: Legacy Effects of Road Salt on Streamwater Concentration. Environ. Sci. Technol. 2008, 42, 410-415.
USGS National Water Information System. Water Quality Samples for the Nation. http://nwis.waterdata.usgs.gov/nwis/qwdata? accessed 4 May 2008.