Skip to Main Content
Ecosystem and understory water and energy exchange for a mature, naturally regenerated pine flatwoods forest in north FloridaAuthor(s): Thomas L. Powell; Gregory Starr; Kenneth L. Clark; Timothy A. Martin; Henry L. Gholz
Source: Canadian Journal of Forest Research 35:1568-1580
Publication Series: Scientific Journal (JRNL)
Station: Northern Research Station
PDF: Download Publication (1.52 MB)
DescriptionEddy covariance was used to measure energy fluxes from July 2000 - June 2002 above the tree canopy and above the understory in a mature, naturally regenerated slash pine (Pinus elliottii Engelm. var. elliottii) - longleaf pine (Pinus palustris Mill.) flatwoods forest. Understory latent energy (eE) and sensible heat (H) fluxes accounted for 45% and 55% of whole-ecosystem fluxes, respectively, with strong seasonal variation in the proportion of eE attributable to the understory. The partitioning of net radiation (Rnet) to eE and H also changed seasonally, with half-hourly mean ecosystem H in the winter peaking at 175 W?m-2, almost twice as large as eE . In contrast, half-hourly ecosystems eE and H remained almost equal throughout the day in July and August, with mean midday peaks of approximately 200 W?m-2. Maximum hourly evapotranspiration (ET) in the months of July and August was 0.32 and 0.29 mm?h-1 or 2000 and 2001, respectively. For a variety of environmental conditions, mean daily ET was approximately 2.7 mm in the summer and 1.3 mm in the winter. Annual ET for the first year was 832 mm, or 87% of annual precipitation (956 mm). Although leaf area index was higher in the second year, annual ET was only 676 mm, which is considerably lower than that of the previous year, but it still accounted for approximately the same proportion (84%) of the much lower annual precipitation (811 mm). Canopy conductance declined as soils dried, changing patterns of partitioning of Rnet to eE.
- Check the Northern Research Station web site to request a printed copy of this publication.
- Our on-line publications are scanned and captured using Adobe Acrobat.
- During the capture process some typographical errors may occur.
- Please contact Sharon Hobrla, email@example.com if you notice any errors which make this publication unusable.
- 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.
CitationPowell, Thomas L.; Starr, Gregory; Clark, Kenneth L.; Martin, Timothy A.; Gholz, Henry L. 2005. Ecosystem and understory water and energy exchange for a mature, naturally regenerated pine flatwoods forest in north Florida. Canadian Journal of Forest Research 35:1568-1580
- Genetic variation in basal area increment phenology and its correlation with growth rate in loblolly and slash pine families and clones
- Local and general above-stump biomass functions for loblolly pine and slash pine trees
- Use of near infared spectroscopy to predict the mechanical properties of six softwoods
XML: View XML