Evapotranspiration and water yield of a pine-broadleaf forest are not altered by long-term atmospheric [CO 2 ] enrichment under native or enhanced soil fertilityAuthor(s): Eric J. Ward; Ram Oren; Hyun Seok Kim; Dohyoung Kim; Pantana Tor-ngern; Brent E. Ewers; Heather R. McCarthy; A. Christopher Oishi; Diane E. Pataki; Sari Palmroth; Nathan G. Phillips; Karina V.R. Schäfer
Source: Global Change Biology
Publication Series: Scientific Journal (JRNL)
Station: Southern Research Station
Download Publication (1.0 MB)
Changes in evapotranspiration (ET) from terrestrial ecosystems affect their water yield (WY), with considerable ecological and economic consequences. Increases in surface runoff observed over the past century have been attributed to increasing atmospheric CO2 concentrations resulting in reduced ET by terrestrial ecosystems. Here, we evaluate the water balance of a Pinus taeda (L.) forest with a broadleaf component that was exposed to atmospheric [CO2] enrichment (ECO2; +200 ppm) for over 17 years and fertilization for 6 years, monitored with hundreds of environmental and sap flux sensors on a half-hourly basis. These measurements were synthesized using a one-dimensional Richard's equation model to evaluate treatment differences in transpiration (T), evaporation (E), ET, and WY. We found that ECO2 did not create significant differences in stand T, ET, or WY under either native or enhanced soil fertility, despite a 20% and 13% increase in leaf area index, respectively. While T, ET, and WY responded to fertilization, this response was weak (<3% of mean annual precipitation). Likewise, while E responded to ECO2 in the first 7 years of the study, this effect was of negligible magnitude (<1% mean annual precipitation). Given the global range of conifers similar to P. taeda, our results imply that recent observations of increased global streamflow cannot be attributed to decreases in ET across all ecosystems, demonstrating a great need for model–data synthesis activities to incorporate our current understanding of terrestrial vegetation in global water cycle models.
- You may send email to firstname.lastname@example.org to request a hard copy of this publication.
- (Please specify exactly which publication you are requesting and your mailing address.)
- We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
- This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.
CitationWard, Eric J.; Oren, Ram; Kim, Hyun Seok; Kim, Dohyoung; Tor-ngern, Pantana; Ewers, Brent E.; McCarthy, Heather R.; Oishi, A. Christopher; Pataki, Diane E.; Palmroth, Sari; Phillips, Nathan G.; Schäfer, Karina V.R. 2018. Evapotranspiration and water yield of a pine-broadleaf forest are not altered by long-term atmospheric [CO2] enrichment under native or enhanced soil fertility . Global Change Biology. https://doi.org/10.1111/gcb.14363.
- Water yield responses to climate change and variability across the North–South Transect of Eastern China (NSTEC)
- Biomass increases attributed to both faster tree growth and altered allometric relationships under long‐term carbon dioxide enrichment at a temperate forest
- Terrestrial water fluxes dominated by transpiration: Comment
XML: View XML