Skip to Main Content
Experimental Acidification Causes Soil Base-Cation Depletion at the Bear Brook Watershed in MaineAuthor(s): Ivan J. Fernandez; Lindsey E. Rustad; Stephen A. Norton; Jeffrey S. Kahl; Bernard J. Cosby
Source: Soil Science Society of America Journal. 67: 1909-1919.
Publication Series: Miscellaneous Publication
Station: Northeastern Research Station
PDF: Download Publication (1.2 MB)
DescriptionThere is concern that changes in atmospheric deposition, climate, or land use have altered the biogeochemistry of forests causing soil base-cation depletion, particularly Ca. The Bear Brook Watershed in Maine (BBWM) is a paired watershed experiment with one watershed subjected to elevated N and S deposition through bimonthly additions of (NH4)2SO4. Quantitative soil excavations in 1998 measured soil pools of exchangeable base cations 9 yr after treatments began. Stream sampling at the weirs on a weekly and event basin, and weekly precipitation sampling, were used for input-output estimates. The treated watershed had lower concentrations of exchangeable Ca and Mg in all horizons, with evidence for the greater depletion in the 0 horizon compared to underlying mined soh, and in softwoods compared to hardwoods. This difference between watersheds is interpreted to be treatment-induced base-cation depletion, which was reinforced by model simulations. The difference between watersheds was 66 and 27 kg ha-' of exchangeable Ca and Mg, respectively, after accounting for soil mass differences between watersheds. This was comparable with tbe total cumulative excess stream Ca and Mg export in West Bear after 9 yr of treatment of 55 and 11 kg ha-', respectively. Model simulations of watershed response to treatments predicted excess soil exchangeable Ca and Mg losses in the treated watershed of 47 and 9 kg ha-', respectively. These results indicate that the response to a step-increase in N and S deposition during the first decade of treatments in this experimental forested watershed was to invoke cation exchange buffering, resulting in a net decline in soil exchangeable base cations.
- 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, firstname.lastname@example.org 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.
CitationFernandez, Ivan J.; Rustad, Lindsey E.; Norton, Stephen A.; Kahl, Jeffrey S.; Cosby, Bernard J. 2003. Experimental Acidification Causes Soil Base-Cation Depletion at the Bear Brook Watershed in Maine. Soil Science Society of America Journal. 67: 1909-1919.
- The Fernow Watershed Acidification Study: ecosystem acidification, nitrogen saturation and base cation leaching
- The effects of doubling annual N and S deposition on foliage and soil chemistry and growth of Japanese larch (Larix leptolepis Sieb. and Zucc.) in north central West Virginia
- Using Ion-Exchange Resins to Study Soil Response to Experimental Watershed Acidification
XML: View XML