Complex terrain alters temperature and moisture limitations of forest soil respiration across a semiarid to subalpine gradient

Journal of Geophysical Research: Biogeosciences
By: , and 

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Abstract

Forest soil respiration is a major carbon (C) flux that is characterized by significant variability in space and time. We quantified growing season soil respiration during both a drought year and a nondrought year across a complex landscape to identify how landscape and climate interact to control soil respiration. We asked the following questions: (1) How does soil respiration vary across the catchments due to terrain-induced variability in moisture availability and temperature? (2) Does the relative importance of moisture versus temperature limitation of respiration vary across space and time? And (3) what terrain elements are important for dictating the pattern of soil respiration and its controls? Moisture superseded temperature in explaining watershed respiration patterns, with wetter yet cooler areas higher up and on north facing slopes yielding greater soil respiration than lower and south facing areas. Wetter subalpine forests had reduced moisture limitation in favor of greater seasonal temperature limitation, and the reverse was true for low-elevation semiarid forests. Coincident climate poorly predicted soil respiration in the montane transition zone; however, antecedent precipitation from the prior 10 days provided additional explanatory power. A seasonal trend in respiration remained after accounting for microclimate effects, suggesting that local climate alone may not adequately predict seasonal variability in soil respiration in montane forests. Soil respiration climate controls were more strongly related to topography during the drought year highlighting the importance of landscape complexity in ecosystem response to drought.

Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Complex terrain alters temperature and moisture limitations of forest soil respiration across a semiarid to subalpine gradient
Series title Journal of Geophysical Research: Biogeosciences
DOI 10.1002/2014JG002802
Volume 120
Issue 4
Year Published 2015
Language English
Publisher American Geophysical Union
Publisher location Richmond, VA
Contributing office(s) Geosciences and Environmental Change Science Center
Description 17 p.
First page 707
Last page 723
Online Only (Y/N) N
Additional Online Files (Y/N) N