Do plant functional traits predict carbon sequestration in grasslands? Katja Klumpp Marie-Terese Sebastia Jean François Soussana

C sequestration (Mg ha-1 yr-1) Röscher et al. 2005 Ecology Letters Aboveground productivity Tilman et al. 2006 Science C sequestration (Mg ha-1 yr-1) soil root

With grassland mesocosms low disturbance field treatment high disturbance field treatment 48 monoliths In the field (14-yr) grazing treatments (high and low disturbance) Low – sheep grazed 1x High – sheep grazed 4x + 1cut Experiment Low – uncut High – 5 cut + fertilization low high High ->low Low ->High

Annual C- balance of grassland moonoliths g C m-2yr-1 NEP NBP B-NBP low - low 1668 977 low-high 1623 942 678 high-low 1303 542 high-high 1376 769 465

Below-ground C storage versus NEP and ANPP Trade off!! Increased soil C storage and declined ANPP at low compard to high disturbance. Klumpp et al. 2007 AGEE

Species number affects main C fluxes (including C sequestration ) at low, but not at high, experimental disturbance. Closed symbols - low disturbance Open symbols - high disturbance (Klumpp et al. Submitted)

Correlation between C-fluxes and community scale above and belowground plant traits GPP Rs Reco NEP NBP ANPP Soil C storage SOM -new -old SpeciesNb -0.47 -0.23 -0.63 0.26 0.05 -0.27 0.36 -0.44 0.66 Leaf-traits SLA -0.28 -0.39 0.15 0.03 -0.31 -0.01 LDMC 0.20 0.19 0.27 -0.08 0.42 -0.21 0.31 LNC 0.16 0.10 0.00 -0.51 0.47 -0.26 0.39 -0.33 Root&Rhizome SpecificLength 0.24 0.09 -0.29 -0.43 0.58 -0.55 0.11 -0.65 Dens 0.35 0.46 0.56 0.04 Diameter -0.45 -0.56 0.18 0.29 -0.60 0.48 0.69 NC 0.40 -0.06 0.14 0.13 -0.12 0.33 -0.17

direct (experimental disturbance and year) ANCOVA, testing direct (experimental disturbance and year) indirect (plant functional traits and species number) ANCOVA (n=32) ANPP Soil C storage Soil-old Specfic Length 0.03 0.04 0.02 Species NB 0.31 0.48 0.00 Year 0.54 0.90 Experiment 0.01 0.22 Year*Experiment 0.37 0.13 0.45 R2 0.67 0.43 0.71 p-model *** *

Campaign on Flux-trait comparison of european grassland Country Site Participation 1 CZ Bilykriz 2 ES Val d’Alinya 3 F Laqueuille EXT Laqueuille INT 4 HU Bungac 5 CH Oensingen No manpower 6 NL Cabauw Haastrecht Hostermeer Reeuwjk 7 DE Grillenburg 8 PT Tojal Cut already 9 IT Amplero 10 Mitra 11 Majadas

Gross primary productivity and NEE versus species number

SLA versus leaf dry matter content and leaf N content On species level: SLA versus leaf dry matter content and leaf N content Each species is weight by the percentage of its presence ☻ community scale

Gross primary productivity and NEE versus community scale traits GPP NEE

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