000198578 001__ 198578
000198578 005__ 20190829172524.0
000198578 0247_ $$2doi$$a10.1007/s10533-013-9928-z
000198578 022__ $$a0168-2563
000198578 02470 $$2ISI$$a000333080400017
000198578 037__ $$aARTICLE
000198578 245__ $$aLong-term organic carbon turnover rates in natural and semi-natural topsoils
000198578 260__ $$bSpringer$$c2014$$aDordrecht
000198578 269__ $$a2014
000198578 300__ $$a16
000198578 336__ $$aJournal Articles
000198578 520__ $$aWe combined published and new radiocarbon and ancillary data for uncultivated topsoils (typically 15 cm depth), to make two databases, one for the United Kingdom (133 sites), and one global (114 sites). Forest topsoils are significantly higher in radiocarbon than non-forest soils, indicating greater enrichment with "bomb carbon" and therefore faster C turnover, if steady-state conditions are assumed. Steady-state modelling, taking into account variations in atmospheric (CO2)-C-14, including the effects of 20th century nuclear weapons testing and radioactive decay, was used to quantify soil carbon turnover rates. Application of a model with variable slow (20 year mean residence time, MRT) and passive (1,000 year MRT) carbon pools partitioned the topsoil C approximately equally, on average, between the two pools when the entire data set was considered. However, the mean slow:passive ratio of 0.65:0.35 for forest soil was highly significantly different (p < 0.001) from the 0.40:0.60 ratio for non-forest soils. Values of the slow and passive fractions were normally distributed, but the non-forest fractions showed greater variation, with approximately twice the relative standard deviations of the forest values. Assuming a litter input of 500 g C m(-2) a(-1), average global C fluxes (g C m(-2) a(-1)) of forest soils are estimated to be 298 (through a fast pool of MRT 1 year), 200 (slow pool) and 2.0 (passive pool), while for non-forest soils, respective average fluxes of 347, 150 and 3.3 g C m(-2) a(-1) are obtained. The results highlight the widespread global phenomenon of topsoil C heterogeneity, and indicate key differences between forest and non-forest soils relevant for understanding and managing soil C.
000198578 6531_ $$aCarbon
000198578 6531_ $$aModelling
000198578 6531_ $$aRadiocarbon
000198578 6531_ $$aSoil
000198578 6531_ $$aTurnover
000198578 700__ $$0246025$$g221827$$uEcole Polytech Fed Lausanne, Sch Architecture Civil & Environm Engn ENAC, Lab Ecol Syst ECOS, CH-1015 Lausanne, Switzerland$$aMills, R. T. E.
000198578 700__ $$uLancaster Environm Ctr, Ctr Ecol & Hydrol, Lancaster LA1 4AP, England$$aTipping, E.
000198578 700__ $$uNat Environm Res Council Radiocarbon Facil Enviro, E Kilbride G75 0QF, Lanark, Scotland$$aBryant, C. L.
000198578 700__ $$aEmmett, B. A.
000198578 773__ $$j118$$tBiogeochemistry$$k1-3$$q257-272
000198578 909C0 $$xU11021$$pECOS$$0252129
000198578 909CO $$qENAC$$particle$$ooai:infoscience.tind.io:198578
000198578 917Z8 $$x133834
000198578 937__ $$aEPFL-ARTICLE-198578
000198578 973__ $$rREVIEWED$$sPUBLISHED$$aEPFL
000198578 980__ $$aARTICLE