How CO2 Respiration Near the Mountain Research
Station Relates to Climate Change
By: Sara CrepinsekEBIO 4100 Spring 2010
Mountain Research Station, University of Colorado, Boulder
– Winter Ecology
Introduction
Global Climate Change How microbs may be affected by snowpack
depth Temperature/precipitation trends
Question Are CO2 respiration levels
determined by the amount of snow pack above the soil as well as the precipitation and temperature amounts around the area?
Methods/Data Collection
Snow pits dug near C-1 site Snow pits dug near Mountain Research
Station Snow depths range from 3-70 cm
Search for variation in snow depths for sites CO2 fluxes range from 1.5-16 ppm
Methods: Calculations Graphed Data Points Trendline and Equation Function Calculations
33 62 91 120450460470480490500510520530
f(x) = 9.4 x + 481R² = 0.997291196388262
f(x) = 6.6 x + 472.5R² = 0.999082568807339
Site 1
Site1Series1Linear (Site1Series1)Site1Series2Linear (Site1Series2)
Time (sec)
CO2
(ppm
)
Mean Slopes8
Mean R20.998185
SD1.979898987
SE1.4
Compilation of Snow Depth and CO2 Flux
DataSnow Depth (cm)
Mean CO2 Flux
(ppm)
SE (+/-)
70 16.0333 1.831552 8.85 1.7552 8 1.439 5.95 1.0534 6.05 1.6522 4.1 13 1.5666 0.2962
0 10 20 30 40 50 60 70 8002468
1012141618
Snow Depth v CO2 Flux
Depth v Flux
Snow Depth (cm)
CO2
Flux
(pp
m)
Summary of Snow Depth Data
Increased respiration with increased snow depth Almost linear growth of CO2 flux with snow
depth Possible source of error at one of the sites
Climatological Snow Water Equivalent Data of Niwot Station
(Feb-April)(Natural Resources Conservation Services, 2010)
1966
1968
1970
1972
1974
1976
1978
1980
1982
1984
1986
1988
1990
1992
1994
1996
1998
2000
2002
2004
2006
2008
0
10
20
30
40
50
60
70
f(x) = − 0.062624584717608 x + 36.0870431893688R² = 0.00557961638230253
Snotel Data
Snotel DataLinear (Snotel Data)
Year
Snow
Wat
er E
quiv
alen
t (in
ch)
C-1 Annual Precipitation Summary
Data(Mountain Research Station, 2010)
1952
1955
1958
1961
1964
1967
1970
1973
1976
1979
1982
1985
1988
1991
1994
1997
2000
2003
0
20
40
60
80
100
120
f(x) = 0.0198355104015482 x + 66.2870827285922R² = 0.000394934197607721
C-1 Annual Summary
C-1 Annual SummaryLinear (C-1 Annual Summary)
Year
Prec
ipita
tion
(cm
)
Summary of Precipitation Data
Snotel data: Only available for months Feb-April (Natural Resources Conservation Services, 2010) Shows no significant increase/decrease
C-1 data: Annual data compilation (Mountain Research Station, 2010) Shows no significant increase/decrease
C-1 Annual Air Temperature Summary Data
(Mountain Research Station, (2010)
1952195
5195
8196
1196
4196
7197
0197
3197
6197
9198
2198
5198
8199
1199
4199
7200
0200
3
-3
-2
-1
0
1
2
3
4
f(x) = 0.0225286244154169 x + 1.00870827285922R² = 0.10597739970151
C-1 Summary Temp
C-1 Summary TempLinear (C-1 Summary Temp)
Year
Tem
pera
ture
(de
g C)
Average Soil Temperatures vs. CO2
FluxMean CO2 Flux (ppm)
Ave Temp (deg C)
Snow Depth
16.0333 0.05 708 -1.45 52
1.5666 -1.65 34.1 -1.8 22
8.85 -1.95 525.95 -1.95 396.05 -2.3 34
-2.5 -2 -1.5 -1 -0.5 0 0.502468
1012141618
Soil Temp vs CO2 Flux
Soil Temp vs CO2 Flux
Ave Temp (deg C)
Mea
n CO
2 Fl
ux (
ppm
)
-2.5 -2 -1.5 -1 -0.5 0 0.50
1020304050607080
Soil Temp vs Snow Depth
Soil Temp vs Snow Depth
Ave Temp (deg C)
Snow
Dep
th (
inch
)
Summary of Temperature Data
C-1 data: Air temperature has been increasing since 1952 (Mountain Research Station, 2010)
Soil Temp data: No significant relationship between soil temp/CO2 flux and soil temp/snow depth
Results
There was an increase in CO2 flux with increased snow depth
No significant change in the amount of precipitation occurring near sites
Increase of air temperature near sites Therefore, air temperature is a concern since
temperature affects snow depth Soil temperature data not significant enough to have
an affect on the focus of my data
Discussion: Snow Depth Data vs. CO2
Flux Winter CO2 flux is dependent upon snow
depth More analysis regarding global climate
change and long term affects on snow depth and CO2 flux under the snow pack Assessment of air and soil temperature
changes in the area may help in analysis
Discussion: Precipitation vs. CO2 Flux
Snotel data shows no increase/decrease in snow water equivalent data for the years 1966-2008
MRS data showed no significant signs of increase/decrease precipitation but possibly still affects snow depth
More analysis needed since temp and precip relate to each other If one increases, should the other
decrease/increase?
Other data shows that ‘nutrient cycling activity’ is in relation to the amount of ‘snow cover’ on the ground during the season (Groffman et al, 2009)
Discussion: Air/Soil Temperature vs. CO2
Flux Air temperatures have been increasing
since 1952 Chaotic correlation between soil
temperature and CO2 flux as well as soil temperature and snow depth Possibly due to site error
Other data shows that if ‘atmospheric CO2’ increases over time, so will the ‘rates of soil respiration’ (Jackson et al, 2009)
Conclusion
CO2 flux has a direct correlation to snow depth
Can not tell if precipitation correlates to CO2 flux However, it should since snow depth does
correlate Air temperature has been increasing and will
therefore affect snow depths
Questions?
References
Groffman PM, Hardy JP, Fisk MC, Fakey TJ, Driscoll CT. (2009). “Climate Variation and Soil Carbon and Nitrogen Cycling Processes in a Northern Hardwood Forest”. Ecosystems. 12(6), 927-943.
Jackson RB, Cook CW, Pippen JS, Palmer SM. (2009). “Increased below ground biomass and soil CO2 fluxes after a decade of carbon dioxide enrichment in a warm-temperate forest”. Ecological Society of America. 90(12), 3352-3366.
Mountain Research Station. (2010). C-1 Annual Summary (1). Retrieved February 14, 2010. http://culter.Colorado.EDU/Climate/Summaries/climc1.html
Natural Resources Conservation Services. (2010). Snow Course and Monthly SNOTEL Data Tables. Retrieved February 14, 2010. ftp://ftp.wcc.nrcs.usda.gov/data/snow/snow_course/table/history/colorado/05j42s.txt.
