Biogeochemistry

, Volume 50, Issue 1, pp 73–93

Throughfall chemistry in a loblolly pine plantationunder elevated atmospheric CO2 concentrations

Authors

  • J. Lichter
    • Department of BotanyDuke University
  • M. Lavine
    • Institute of Statistics and Decision ScienceDuke University
    • Nicholas School of the EnvironmentDuke University
  • K.A. Mace
    • Department of BotanyDuke University
  • D.D. Richter
    • Nicholas School of the EnvironmentDuke University
  • W.H. Schlesinger
    • Department of BotanyDuke University
    • Nicholas School of the EnvironmentDuke University
Article

DOI: 10.1023/A:1006337132631

Cite this article as:
Lichter, J., Lavine, M., Mace, K. et al. Biogeochemistry (2000) 50: 73. doi:10.1023/A:1006337132631

Abstract

Accelerated tree growth under elevatedatmospheric CO2 concentrations may influencenutrient cycling in forests by (i) increasingthe total leaf area, (ii) increasing the supplyof soluble carbohydrate in leaf tissue, and (iii) increasing nutrient-use efficiency. Here wereport the results of intensive sampling andlaboratory analyses of NH4+, NO3, PO43−, H+, K+, Na+,Ca2+, Mg2+, Cl, SO42−, and dissolved organic carbon (DOC) in throughfallprecipitation during the first 2.5+ years of the DukeUniversity Free-Air CO2 Enrichment (FACE)experiment. After two growing seasons, a largeincrease (i.e., 48%) in throughfall deposition of DOCand significant trends in throughfall volume and inthe deposition of NH4+, NO3, H+, and K+ can be attributed to the elevatedCO2 treatment. The substantial increase indeposition of DOC is most likely associated withincreased availability of soluble C in plant foliage,whereas accelerated canopy growth may account forsignificant trends toward decreasing throughfallvolume, decreasing deposition of NH4+,NO3, and H+, and increasing deposition of K+ under elevated CO2. Despiteconsiderable year-to-year variability, there wereseasonal trends in net deposition of NO3,H+, cations, and DOC associated with plant growthand leaf senescence. The altered chemical fluxes inthroughfall suggest that soil solution chemistry mayalso be substantially altered with continued increasesin atmospheric CO2 concentrations in the future.

atmosphere-canopy interactionatmospheric CO2atmospheric depositiondissolved organic carbonFACE experimentloblolly pine (Pinus taeda L.)throughfall chemistry

Copyright information

© Kluwer Academic Publishers 2000