Soil respiration in a northeastern US temperate forest: a 22-year synthesis
2013 (English)In: Ecosphere, ISSN 2150-8925, Vol. 4, no 11, UNSP 140- p.Article in journal (Refereed) Published
To better understand how forest management, phenology, vegetation type, and actual and simulated climatic change affect seasonal and inter-annual variations in soil respiration (R-s), we analyzed more than 100,000 individual measurements of soil respiration from 23 studies conducted over 22 years at the Harvard Forest in Petersham, Massachusetts, USA. We also used 24 site-years of eddy-covariance measurements from two Harvard Forest sites to examine the relationship between soil and ecosystem respiration (R-e). R-s was highly variable at all spatial (respiration collar to forest stand) and temporal (minutes to years) scales of measurement. The response of R-s to experimental manipulations mimicking aspects of global change or aimed at partitioning R-s into component fluxes ranged from similar to 70% to +52%. The response appears to arise from variations in substrate availability induced by changes in the size of soil C pools and of belowground C fluxes or in environmental conditions. In some cases (e.g., logging, warming), the effect of experimental manipulations on R-s was transient, but in other cases the time series were not long enough to rule out long-term changes in respiration rates. Inter-annual variations in weather and phenology induced variation among annual R-s estimates of a magnitude similar to that of other drivers of global change (i.e., invasive insects, forest management practices, N deposition). At both eddy-covariance sites, aboveground respiration dominated R-e early in the growing season, whereas belowground respiration dominated later. Unusual aboveground respiration patterns-high apparent rates of respiration during winter and very low rates in mid-to-late summer-at the Environmental Measurement Site suggest either bias in R-s and R-e estimates caused by differences in the spatial scale of processes influencing fluxes, or that additional research on the hard-to-measure fluxes (e.g., wintertime R-s, unaccounted losses of CO2 from eddy covariance sites), daytime and nighttime canopy respiration and its impacts on estimates of R-e, and independent measurements of flux partitioning (e.g., aboveground plant respiration, isotopic partitioning) may yield insight into the unusually high and low fluxes. Overall, however, this data-rich analysis identifies important seasonal and experimental variations in R-s and R-e and in the partitioning of R-e above-vs. belowground.
Place, publisher, year, edition, pages
2013. Vol. 4, no 11, UNSP 140- p.
ecosystem respiration, eddy covariance, flux partitioning, Harvard Forest, phenology, soil respiration
Environmental Sciences Ecology
IdentifiersURN: urn:nbn:se:su:diva-98068DOI: 10.1890/ES13.00183.1ISI: 000327380900008OAI: oai:DiVA.org:su-98068DiVA: diva2:682296
U.S. National Science Foundation's; Division of Environmental Biology (DEB); Division of Biological Infrastructure (DBI); Long-Term Ecological Research (LTER) program; Faculty Early Career Development (CAREER) program; U.S. Department of Energy's Office of Science (BER); National Institute for Climatic Change Research (NICCR) 2013-12-272013-12-272013-12-27Bibliographically approved