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 120450

460

470

480

490

500

510

520

530

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)

CO

2 (

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 1.8315

52 8.85 1.75

52 8 1.4

39 5.95 1.05

34 6.05 1.65

22 4.1 1

3 1.5666 0.2962

0 10 20 30 40 50 60 70 800

2

4

6

8

10

12

14

16

18

Snow Depth v CO2 Flux

Depth v Flux

Snow Depth (cm)

CO

2 F

lux (

ppm

)

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

Wate

r Equiv

ale

nt

(inch)

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

Pre

cip

itati

on (

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)

1952

1955

1958

1961

1964

1967

1970

1973

1976

1979

1982

1985

1988

1991

1994

1997

2000

2003

-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

(deg C

)

Average Soil Temperatures vs. CO2

FluxMean CO2 Flux (ppm)

Ave Temp (deg C)

Snow Depth

16.0333 0.05 70

8 -1.45 52

1.5666 -1.65 3

4.1 -1.8 22

8.85 -1.95 52

5.95 -1.95 39

6.05 -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)

Mean C

O2 F

lux (

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

Depth

(in

ch)

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.