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

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

3. 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

4. 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

5. 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 AGEE

6. 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)

7. 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

8. 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
*** *

9. 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

10. Gross primary productivity and NEE versus species number

11. 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

12. Gross primary productivity and NEE versus community scale traits
GPP
NEE

13. NEXT Steps