Soil organic matter dynamics in a North America tallgrass prairie after 9 yr of experimental warming
Open Access
- 9 June 2011
- journal article
- Published by Copernicus GmbH in Biogeosciences (online)
- Vol. 8 (6), 1487-1498
- https://doi.org/10.5194/bg-8-1487-2011
Abstract
The influence of global warming on soil organic matter (SOM) dynamics in terrestrial ecosystems remains unclear. In this study, we combined soil fractionation with isotope analyses to examine SOM dynamics after nine years of experimental warming in a North America tallgrass prairie. Soil samples from the control plots and the warmed plots were separated into four aggregate sizes (>2000 μm, 250–2000 μm, 53–250 μm, and 13C and δ15N values. Warming did not significantly effect soil aggregate distribution and stability but increased C4-derived C input into all fractions with the greatest in LF. Warming also stimulated decay rates of C in whole soil and all aggregate sizes. C in LF turned over faster than that in iPOM in the warmed soils. The δ15N values of soil fractions were more enriched in the warmed soils than those in the control, indicating that warming accelerated loss of soil N. The δ15N values changed from low to high, while C:N ratios changed from high to low in the order LF, iPOM, and mSOM due to increased degree of decomposition and mineral association. Overall, warming increased the input of C4-derived C by 11.6 %, which was offset by the accelerated loss of soil C. Our results suggest that global warming simultaneously stimulates C input via shift in species composition and decomposition of SOM, resulting in negligible net change in soil C.Keywords
This publication has 47 references indexed in Scilit:
- Experimental warming and clipping altered litter carbon and nitrogen dynamics in a tallgrass prairieAgriculture, Ecosystems & Environment, 2010
- Large regional-scale variation in C3/C4 distribution pattern of Inner Mongolia steppe is revealed by grazer wool carbon isotope compositionBiogeosciences (online), 2009
- Effects of temperature and fertilization on nitrogen cycling and community composition of an urban lawnGlobal Change Biology, 2008
- Warming increases aboveground plant biomass and C stocks in vascular‐plant‐dominated Antarctic tundraGlobal Change Biology, 2008
- Short-term C4 plant Spartina alterniflora invasions change the soil carbon in C3 plant-dominated tidal wetlands on a growing estuarine IslandSoil Biology and Biochemistry, 2006
- Temperature sensitivity of soil carbon decomposition and feedbacks to climate changeNature, 2006
- Plant nitrogen concentration, use efficiency, and contents in a tallgrass prairie ecosystem under experimental warmingGlobal Change Biology, 2005
- Stable Isotopes in Plant EcologyAnnual Review of Ecology and Systematics, 2002
- Possibilities for carbon sequestration in tropical and subtropical soilsGlobal Change Biology, 1997
- The significance of organic separates to carbon dynamics and its modelling in some cultivated soilsEuropean Journal of Soil Science, 1996