1 / 16

Differences in soil r espiration rates based on vegetation type

Differences in soil r espiration rates based on vegetation type. Maggie Vest Winter Ecology 2013 Mountain Research Station. Introduction. Estimated 20% of the annual soil respiration occurs during the winter. Estimates range from 3% to 50% (Hobbie et al. 2000).

jamuna
Télécharger la présentation

Differences in soil r espiration rates based on vegetation type

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Differences in soil respiration rates based on vegetation type Maggie Vest Winter Ecology 2013 Mountain Research Station

  2. Introduction • Estimated 20% of the annual soil respiration occurs during the winter. • Estimates range from 3% to 50% (Hobbie et al. 2000). • High variability across small spatial scales (Scott-Denton et al. 2002). • Lack of understanding of the controlling factors in mid- and high-latitude systems (Hobbie et al. 2000). • Soil temperature is the best predictor for soil respiration (Scott-Denton et al. 2002).

  3. Vegetation and Soil Respiration • Connection between vegetation type and soil respiration at the landscape scale (Grogan 2012). • Total CO2 flux ranged from 34 to 126g CO2/C m^2 for various vegetation types in the low arctic tundra in Canada. • Ecosystem-specific interactions between snow depth, vegetation cover, moisture, and litter production also affect CO2 flux • Different decomposition rates between evergreens and deciduous trees (Hobbie et al. 2000).

  4. Hypothesis • The aim of this study is to determine the degree of significance that surrounding vegetation has on soil respiration during wintertime. • Question: Does the surrounding vegetation significantly impact soil respiration rates in the subalpine forests? • Hypothesis: Deciduous trees are likely to have higher rates of soil respiration than conifers.

  5. Methods • 3 vegetation types • Aspen • Lodgepole • Spruce • 3 Replicates for each site • Trees with 30cm< snow depth • Measured CO2 concentrations over a 2 minute period • Recorded site features: temperature of soil surface, snow depth, soil moisture, amount of organic litter, litter composition

  6. Results Aspen-Lodgepole P Value: 0.11 Aspen-Spruce P Value: 0.46 Lodgepole-Spruce P Value: 0.10

  7. Other Factors Affecting Soil RespirationSnow Depth

  8. Other Factors Affecting Soil RespirationSoil Temperature

  9. Other Factors Affecting Soil RespirationGround Litter

  10. Results • Overall results were insignificant • Aspen CO2 flux and snow depth were only significant data • Results suggest expected trends of aspens having higher soil respiration than the evergreens

  11. Discussion • Vegetation potentially impacts the rate of soil respiration • Errors • Short time scale of project • Small sample size • Further research is needed in order to determine the degree of significance that vegetation has on soil respiration rates.

  12. Summary • Winter time soil respiration has the potential to significantly impact the annual net carbon balance (Grogan 2012). • Results suggest expected trends of aspens having higher soil respiration than the evergreens. • Further research is needed in order to determine the degree of significance that vegetation has on soil respiration rates.

  13. Acknowledgements • Thank to Rob for being a field partner • Thanks to Tim, Derek, and the CU Mountain Research Center The End

  14. References • Brooks, Paul D., S. K. Schmidt, and M. W. Williams. 1997. Winter production of CO2 and N2O from alpine tundra: environmental controls and relationship in inter-system C and N fluxes. Oecologia110: 403-413. • Grogan, Paul. 2012. Cold season respiration across a low arctic landscape: the influences of vegetation type, snow depth, and interannual climatic variation. Arctic, Antarctic, and Alpine Research 44:446-456. 1938-4246-44.4.446. • Hobbie, Sarah E., J. P. Schimel, S. E. Trumbore, and J. R. Randersons. 2000. Controls over carbon storage and turnover in high-latitude soils. Global Change Biology6:196-210. • Scott-Denton, Laura, K. L. Sparks, R. K. Monson. 2003. Spatial and temporal controls of soil respiration rate in a high-elevation, subalpine forest. Soil Biology and Biochemistry 35: 525-534. • Schadt, Christopher, M. P. Martin, D. A. Lipson, S. K. Schmidt. 2003. Seasonal Dynamics of previously unknown fungal lineages in tundra soils. Science 302: 1359-1361. • Tuomi, M, T. Thum, H. Jarvinen, S. Fronzek, B. Berg, M. Harmon, J. A. Trofymow, S. Sevanto, J. Liski. 2009. Leaf litter decomposition-estimates of global variability based on Yasso07 model. Ecological Modeling 220: 3362-3371.

  15. Appendix CO2 Flux

  16. AppendixResults

More Related