Soil stores approximately twice as much carbon as the atmosphere and fluctuations in the size of the soil carbon pool directly influence climate conditions. We used the Nutrient Network global change experiment to examine how anthropogenic nutrient enrichment might influence grassland soil carbon storage at a global scale. In isolation, enrichment of nitrogen and phosphorous had minimal impacts on soil carbon storage. However, when these nutrients were added in combination with potassium and micronutrients, soil carbon stocks changed considerably, with an average increase of 0.04 KgCm(-2) year(-1) ( standard deviation 0.18 KgCm(-2) year(-1)). These effects did not correlate with changes in primary productivity, suggesting that soil carbon decomposition may have been restricted. Although nutrient enrichment caused soil carbon gains most dry, sandy regions, considerable absolute losses of soil carbon may occur in high-latitude regions that store the majority of the world's soil carbon. These mechanistic insights into the sensitivity of grassland carbon stocks to nutrient enrichment can facilitate biochemical modelling efforts to project carbon cycling under future climate scenarios.
1.Swiss Fed Inst Technol, Inst Integrat Biol, Univ Str 16, CH-8092 Zurich, Switzerland 2.Univ Minnesota, Dept Ecol Evolut & Behav, 1479 Gortner Ave, St Paul, MN 55108 USA 3.Netherlands Inst Ecol, Dept Terr Ecol, Droevendaalsesteeg 10, NL-6708 PB Wageningen, Netherlands 4.Utah State Univ, Dept Wildland Resources, Logan, UT 84322 USA 5.Utah State Univ, Ctr Ecol, Logan, UT 84322 USA 6.Queensland Univ Technol, Gardens Point Campus, Brisbane, Qld 40000, Australia 7.Arizona State Univ, Sch Life Sci, Temple, TX USA 8.Arizona State Univ, Global Drylands Ctr, Temple, TX USA 9.Univ Pretoria, Mammal Res Inst, Dept Zool & Entomol, Pretoria, South Africa 10.Pacific Northwest Natl Lab, Earth & Biol Sci Directorate, Richland, WA 99352 USA 11.Iowa State Univ, Dept Ecol Evolut & Organismal Biol, Ames, IA 50010 USA 12.Univ Nebraska, Sch Biol Sci, Lincoln, NE 68588 USA 13.Univ Kentucky, Dept Plant & Soil Sci, Lexington, KY 40546 USA 14.Univ Guelph, Dept Integrat Biol, Guelph, ON N1G 2W1, Canada 15.Natl Univ INTA CONICET, Dept Forestry Agr & Water, Santa Cruz, Patagonia, Argentina 16.CSIRO Land & Water, Private Bag 5, Wembley, WA 6913, Australia 17.Univ Lancaster, Lancaster Environm Ctr, Lancaster LA1 4YQ, England
Recommended Citation:
Crowther, T. W.,Riggs, C.,Lind, E. M.,et al. Sensitivity of global soil carbon stocks to combined nutrient enrichment[J]. ECOLOGY LETTERS,2019-01-01,22(6):936-945