Advertisement

Ecosystems

, Volume 7, Issue 5, pp 468–481 | Cite as

Components and Controls of Water Flux in an Old-growth Douglas-fir–Western Hemlock Ecosystem

  • Michael H. UnsworthEmail author
  • Nathan Phillips
  • T. Link
  • Barbara J. Bond
  • Matthias Falk
  • Mark E. Harmon
  • Thomas M. Hinckley
  • Danny Marks
  • Kyaw Tha Paw U
Article

Abstract

We report measurements of rates of sap flow in dominant trees, changes in soil moisture, and evaporation from coarse woody debris in an old-growth Douglas-fir–western hemlock ecosystem at Wind River, Washington, USA, during dry periods in summer. The measurements are compared with eddy-covariance measurements of water-vapor fluxes above the forest (Ee) and at the forest floor (Eu) to examine the components of ecosystem water loss and the factors controlling them. Daily values of Eu were about 10% of Ee. Evaporation from coarse woody debris was only about 2% of Ee. Transpiration (Et), estimated by scaling sap-flow measurements accounted for about 70% of (Ee− Eu); transpiration from subdominant trees may account for the remainder. The daily total change in soil moisture (Es) in the top 30 cm was larger than the net change, probably because of hydraulic redistribution of soil water by roots. Observed differences between Es and Ee were probably because roots also extract water from greater depth, and/or because the measuring systems sample at different spatial scales. The ratio of Et to Es decreased with decreasing soil water content, suggesting that partitioning in water use between understory and overstory changed during the season. The rate of soil drying exceeded Ee early in the day, probably because water vapor was being stored in canopy air space and condensed or adsorbed on tree stems, lichens, and mosses. The daily variation of Ee with vapor-pressure deficit showed strong hysteresis, most likely associated with transpiration of water stored in tree stems and branches.

Keywords

sap flow soil moisture eddy covariance transpiration evaporation condensation hydraulic redistribution hysteresis 

Notes

Acknowledgements

We thank Tom King for microclimate data, and Dave Shaw for logistical support during many of these measurements. We also thank two anonymous reviewers for several very helpful suggestions. Much of this research was supported by the Office of Science, Biological and Environmental Research Program (BER), US Department of Energy (DOE), through the Western Regional Center (WESTGEC) under of the National Institute for Global Environmental Change (NIGEC) through Cooperative Agreement DE-FC03-90ER61010. Other support was from the National Science Foundation (DEB 9632929). Any opinions, findings, and conclusions or recommendations expressed herein are those of the authors and do not necessarily reflect the view of the DOE.

References

  1. Amiro, BD, Wuschke, EE 1987Evapotranspiration from a boreal forest drainage basin using an energy balance/eddy covariance techniqueBoundary-layer Meteorol3812539Google Scholar
  2. Anthoni, PM, Law, BE, Unsworth, MH 1999Carbon and water vapor exchange of an open-canopied ponderosa pine ecosystemAgric For Meteorol9515168CrossRefGoogle Scholar
  3. Baldocchi, DD, Meyers, TP 1991Trace gas exchange above the floor of a deciduous forest: 1. Evaporation and CO2 effluxJ Geophys Res96727185Google Scholar
  4. Baldocchi, DD, Vogel, CA 1996A comparative study of water vapor, energy and CO2 flux densities above and below a temperate broadleaf and a boreal pine forestTree Physiol16516PubMedGoogle Scholar
  5. Baldocchi, DD, Vogel, CA 1997Seasonal variation of energy and water vapor exchange rates above and below a boreal jack pine forest canopyJ Geophys Res102939951CrossRefGoogle Scholar
  6. Black, TA, Kelliher, FM 1989Processes controlling understory evapotranspirationPhilos Trans R Soc Lond [B]32420731Google Scholar
  7. Blanken, PD, Black, TA, Yang, PC, Neumann, HH, Nesic, Z, Staebler, R, Hartog, G, Novak, MD, Lee, X 1997Energy balance and canopy conductance of a boreal aspen forest: partitioning overstory and understory componentsJ Geophys Res102915927CrossRefGoogle Scholar
  8. Brooks, JR, Meinzer, FC, Coulombe, R, Gregg, J 2002Hydraulic redistribution of soil water during summer drought in two contrasting Pacific Northwest coniferous forestsTree Physiol2211071117PubMedGoogle Scholar
  9. Burgess, SSO, Adams, MA, Turner, NC, Ong, CK 1998The redistribution of soil water by tree root systemsOecologia (Berl)11530611CrossRefGoogle Scholar
  10. Cermak, J, Kucera, J, Baurle, W, Hinckley, TM .In reviewWater storage in old-growth Douglas-fir trees: assessment from sap flow, tissue water content and dimensional changes..Google Scholar
  11. Cienciala, E, Lindroth, A, Cermak, J, Hallgren, J-E, Kucera, J 1994The effects of water availability on transcription, water potential and growth of Picea abies during a growing seasonJournal of Hydrology1555771CrossRefGoogle Scholar
  12. Dawson, TE 1993Hydraulic lift and plant water use: implications for water balance, performance and plant–plant interactionsOecologia (Berl)9556574Google Scholar
  13. Dawson, TE 1996Determining water use by trees and forests from isotopic, energy balance and transpiration analyses: the roles of tree size and hydraulic liftTree Physiol1626372PubMedGoogle Scholar
  14. Denmead, OT 1984Plant physiological methods for studying evapotranspiration: problems of telling the forest from the treesAgric Water Manage816789CrossRefGoogle Scholar
  15. Diawara, A, Loustau, D, Berbigier, P 1991Comparison of two methods for estimating the evaporation of a Pinus pinaster (Ait.) stand: sap flow and energy blance with sensible heat flux measurements by an eddy covariance methodAgricultural and Forest Meteorology544966CrossRefGoogle Scholar
  16. Fitzjarrald, DR, Moore, KE 1994Growing season boundary layer climate and surface exchanges in the northern lichen woodlandJ Geophys Res991899917CrossRefGoogle Scholar
  17. Fritschen, LJ, Doraiswamy, P 1973Dew: an addition to the hydrologic balance of Douglas firWater Resour Res989194Google Scholar
  18. Goldstein, G, Andrade, JL, Meinzer, FC, Holbrook, NM, Cavelier, J, Jackson, P, Celis, A 1998Stem water storage and diurnal patterns of water use in tropical forest canopy treesPlant Cell Environ21397406CrossRefGoogle Scholar
  19. Granier, A 1985Une nouvelle methode pour la mesure de flux de seve brute dans le tronc des arbesAnnales des Sciences Forestieres42193200Google Scholar
  20. Granier, A 1987Evaluation of transpiration in a Douglas-fir stand by means of sap flow measurementsTree Physiology3309320PubMedGoogle Scholar
  21. Harmon, ME, Bible, K, Ryan, MG, Shaw, DC, Chen, H, Klopatek, J, Li, X 2004Production, respiration, and overall carbon balance in an old-growth PseudotsugaTsuga forest ecosystemEcosystems7.[this issue]Google Scholar
  22. Hogg, EH, Black, TA, Hartog, G, Neumann, HH, Zimmermann, R, Hurdle, PA, Blanken, PD, Nesic, Z, Yang, PC, Staebler, R, others,  1997A comparison of sap flow and eddy fluxes of water vapor from a boreal deciduous forestJ Geophys Res10292937CrossRefGoogle Scholar
  23. Jarvis, PG, Masseder, JM, Hale, SE, Moncrieff, JB, Rayment, M, Scott, SL 1997Seasonal variation of carbon dioxide, water vapor and energy exchanges of a boreal black spruce forestJ Geophys Res102953966Google Scholar
  24. Kelliher, FM, Black, TA, Price, DT 1986Estimating the effects of understory removal from a Douglas fir. forest using a two-layer canopy evapotranspiration modelWater Resour Res22189199Google Scholar
  25. Kelliher, FM, Leuning, R, Schulze, E-D 1993Evaporation and canopy characteristics of coniferous forests and grasslandsOecologia (Berl)9515363Google Scholar
  26. Kelliher, FM, Whitehead, D, McAneney, KJ, Judd, MJ 1990Partitioning evapotranspiration into tree and understory components in two young Pinus radiata DDon stands. Agric For Meteorol5021127CrossRefGoogle Scholar
  27. Monteith, JL, Butler, D 1979Dew and thermal lag: a model for cocoa podsQ J R Meteorol Soc10520715CrossRefGoogle Scholar
  28. Monteith, JL, Unsworth, MH 1990Principles of environmental physics2Edward ArnoldLondon291Google Scholar
  29. Oren, R, Phillips, N, Katul, G, Ewers, E, Pataki, DE 1998Scaling xylem sap flux and soil water balance and calculating variance: a method for partitioning water flux in forestsAnn Sci For55191216Google Scholar
  30. Paltineanu, IC, Starr, JL 1997Real-time soil water dynamics using multisensor capacitance probes: laboratory calibrationSoil Science Society of America Journal6115761585Google Scholar
  31. Parker, GG, Harmon, ME, Lefsky, MA, Chen, J, Pelt, R, Weiss, SB, Thomas, SC, Winner, WE, Shaw, DC, Franklin, JF 2004Three-dimensional structure of an old-growth Pseudotsuga-Tsuga canopy and its implications for radiation balance, microclimate, and gas exchangeEcosystems7.[this issue]Google Scholar
  32. Paw U, KT, Falk, M, Suchanek, TH, Ustin, SL, Chen, J, Park, Y-S, Winner, WE, Thomas, SC, Hsiao, TC, Shaw, RH 2004Carbon dioxide exchange between an old-growth forest and the atmosphereEcosystems7.[this issue]Google Scholar
  33. Phillips, N, Bond, BJ, McDowell, NG, Ryan, MG 2002Canopy and hydraulic conductance in young, mature and old Douglas-fir treesTree Physiol2220511PubMedGoogle Scholar
  34. Price, DT, Black, TA 1990Effects of short-term variation in weather on diurnal canopy CO2 flux and evapotranspiration of a juvenile Douglas-fir standAgric For Meteorol5013950CrossRefGoogle Scholar
  35. Roberts, J 1983Forest transpiration: a conservative hydrological processJ Hydrol6613341CrossRefGoogle Scholar
  36. Ryan, MJ, Yoder, BJ 1997Hydraulic limits to tree height and tree growthBioscience4723542Google Scholar
  37. Schuepp, PH, Leclerc, MY, MacPherson, JI, Desjardins, RL 1990Footprint prediction of scalar fluxes from analytical solutions of the diffusion equationBoundary-layer Meteorol5035573Google Scholar
  38. Schulze, ED, Cermak, J, Matyssek, R, Penka, M, Zimmermann, R, Vasicek, F, Gries, W, Kucera, J 1985Canopy transpiration and water fluxes in the xylem of the trunk of Larix and Picea trees: a comparison of xylem flow, porometer and cuvette measurementsOecologia (Berl)6647583Google Scholar
  39. Seyfried, MS, Murdock, MD 2001Response of a new soil water sensor to variable soil, water content and temperatureSoil Sci Soc Am J652834Google Scholar
  40. Shaw, DC, Franklin, JF, Bible, K, Klopatek, J, Freeman, E, Greene, S, Parker, GG 2004Ecological setting of the Wind River old-growth forestEcosystems7.[this issue]Google Scholar
  41. Tan, CS, Black, TA, Nnyamah, JU 1978A simple vapor diffusion model applied to a thinned Douglas-fir standEcology59 122129Google Scholar
  42. Thomas, SC, Winner, WE 2000Leaf area index of an old-growth Douglas-fir forest estimated from direct structural measurements in the canopyCan J For Res30192230CrossRefGoogle Scholar
  43. Yoder, BJ, Ryan, MJ, Waring, RH, Schoettle, AW, Kaufmann, MR 1994Evidence of reduced photosynthetic rates in old treesFor Sci4051327Google Scholar
  44. Winner, WE, Thomas, SC, Berry, JA, Bond, BJ, Cooper, CE, Hinckley, TM, Ehleringer, JR, Fessenden, JE, Lamb, B, McCarthy, S, McDowell, NG, Phillips, N, Williams, M 2004Canopy carbon gain and water use: analysis of old-growth conifers in the Pacific NorthwestEcosystems7.[this issue]Google Scholar

Copyright information

© Springer-Verlag 2004

Authors and Affiliations

  • Michael H. Unsworth
    • 1
    Email author
  • Nathan Phillips
    • 2
  • T. Link
    • 3
  • Barbara J. Bond
    • 4
  • Matthias Falk
    • 5
  • Mark E. Harmon
    • 4
  • Thomas M. Hinckley
    • 6
  • Danny Marks
    • 7
  • Kyaw Tha Paw U
    • 5
  1. 1.College of Oceanic and Atmospheric ScienceOregon State UniversityCorvallisUSA
  2. 2.Geography DepartmentBoston UniversityBostonUSA
  3. 3.Department of Forest ResourcesUniversity of IdahoMoscowUSA
  4. 4.Department of Forest ScienceOregon State UniversityCorvallisUSA
  5. 5.Department of Land, Air and Water ResourcesUniversity of CaliforniaDavisUSA
  6. 6.College of Forest ResourcesUniversity of WashingtonSeattleUSA
  7. 7.Northwest Watershed Research CenterUSDA Agricultural Research ServiceBoiseUSA

Personalised recommendations