You are here: Home
/ Publication Information
Title: Increased nitrogen leaching following soil freezing is due to decreased root uptake in a northern hardwood forest
Author: Campbell, John L.; Socci, Anne M.; Templer, Pamela H.;
Source: Global Change Biology. 20(8): 2663-2673.
Publication Series: Scientific Journal (JRNL)
Description: The depth and duration of snow pack is declining in the northeastern United States as a result of warming air temperatures. Since snow insulates soil, a decreased snow pack can increase the frequency of soil freezing, which has been shown to have important biogeochemical implications. One of the most notable effects of soil freezing is increased inorganic nitrogen losses from soil during the following growing season. Decreased nitrogen retention is thought to be due to reduced root uptake, but has not yet been measured directly. We conducted a 2-year snow-removal experiment at Hubbard Brook Experimental Forest in New Hampshire, USA to determine the effects of soil freezing on root uptake and leaching of inorganic nitrogen simultaneously. Snow removal significantly increased the depth of maximal soil frost by 37.2 and 39.5 cm in the first and second winters, respectively (P < 0.001 in 2008/2009 and 2009/2010). As a consequence of soil freezing, root uptake of ammonium declined significantly during the first and second growing seasons after snow removal (P = 0.023 for 2009 and P = 0.005 for 2010). These observed reductions in root nitrogen uptake coincided with significant increases in soil solution concentrations of ammonium in the Oa horizon (P = 0.001 for 2009 and 2010) and nitrate in the B horizon (P < 0.001 and P = 0.003 for 2009 and 2010, respectively). The excess flux of dissolved inorganic nitrogen from the Oa horizon that was attributable to soil freezing was 7.0 and 2.8 kg N ha-1 in 2009 and 2010, respectively. The excess flux of dissolved inorganic nitrogen from the B horizon was lower, amounting to 1.7 and 0.7 kg N ha-1 in 2009 and 2010, respectively. Results of this study provide direct evidence that soil freezing reduces root nitrogen uptake, demonstrating that the effects of winter climate change on root function has significant consequences for nitrogen retention and loss in forest ecosystems.
Keywords: climate change, root uptake, snow, soil frost, soil solution, stable isotopes
- 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.
- This publication may be available in hard copy. 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.
XML: View XML
Campbell, John L.; Socci, Anne M.; Templer, Pamela H. 2014. Increased nitrogen leaching following soil freezing is due to decreased root uptake in a northern hardwood forest. Global Change Biology. 20(8): 2663-2673.
Get the latest version of the Adobe Acrobat reader or Acrobat Reader for Windows with Search and Accessibility