Seasonal hydrology explains interannual and seasonal variation in carbon and water exchange in a semiarid mature ponderosa pine forest in central Oregon Public Deposited

http://ir.library.oregonstate.edu/concern/defaults/5425kc198

Copyrighted by American Geophysical Union.

Descriptions

Attribute NameValues
Creator
Abstract or Summary
  • We analyzed 7 years (2002–2008) of micrometeorological and concurrent biological observations of carbon and water fluxes at a mature ponderosa pine forest in central Oregon in a semiarid climate. We sought to evaluate the extent that gross primary productivity, net ecosystem exchange, ecosystem respiration, net primary productivity, net ecosystem productivity, tree transpiration, and evapotranspiration varied seasonally and interannually in this ecosystem subjected to varying periods and severity of droughts. To explain variation, we found it necessary to define seasons functionally within a hydroecological year rather than by fixed calendar dates. The interannual variability in growing season length was large (45 days), and the end date was more variable than the onset. Plant-available soil water was the main determinant of carbon fluxes. Spring evapotranspiration primarily used shallow water, whereas summer and fall evapotranspiration drew water from deeper in the soil profile. A multiyear drought (2001–2003) had a more severe and fundamentally different impact on carbon and water cycles than a single-year (2005) drought because of carryover effects in soil water and carbohydrate reserves in plant tissue. Calendar year–based analysis was inadequate to diagnose drought years in precipitation and ecosystem drought response. Extension of meteorological records back to 1982 showed that anomalies were coherent across the region and that the observations represented below-average precipitation and above-average temperatures coherent with a warm-phase Pacific Decadal Oscillation. The carbon sink of this seasonally water-limited ecosystem is anticipated to increase with increasing available soil water during the growing season.
Resource Type
DOI
Date Available
Date Issued
Citation
  • Thomas, C. K., B. E. Law, J. Irvine, J. G. Martin, J. C. Pettijohn, and K. J. Davis (2009), Seasonal hydrology explains interannual and seasonal variation in carbon and water exchange in a semiarid mature ponderosa pine forest in central Oregon, J. Geophys. Res., 114, G04006.
Series
Keyword
Rights Statement
Publisher
Language
Replaces
Additional Information
  • description.provenance : Made available in DSpace on 2010-08-05T21:57:19Z (GMT). No. of bitstreams: 1 Thomas_et_al_JGR_2009.pdf: 1414415 bytes, checksum: 9cb584b3b68727f938c91e4b5fd5ff69 (MD5) Previous issue date: 2009-11-10
  • description.provenance : Approved for entry into archive by Sue Kunda(sue.kunda@oregonstate.edu) on 2010-08-05T21:57:19Z (GMT) No. of bitstreams: 1 Thomas_et_al_JGR_2009.pdf: 1414415 bytes, checksum: 9cb584b3b68727f938c91e4b5fd5ff69 (MD5)
  • description.provenance : Submitted by David Moynihan (dmscanner@gmail.com) on 2010-07-29T17:22:18Z No. of bitstreams: 1 Thomas_et_al_JGR_2009.pdf: 1414415 bytes, checksum: 9cb584b3b68727f938c91e4b5fd5ff69 (MD5)

Relationships

Parents:

This work has no parents.

Last modified

Downloadable Content

Download PDF

Items