1. Soil carbon sequestration under
Miscanthus x giganteus
A large scale survey
Jesko Zimmermann
Jens Dauber
Michael B. Jones

2. Miscanthus
Miscanthus x giganteus
• Ligno-cellulosic or „second generation“ bioenergy crop
• Rhizomatous perennial grass with a C4 photosynthesis
pathway
• Originates in Asia (tropics and subtropics)
• Remarkable adaptability to cool temperate climates
• Introduction subsidised in Ireland
Soil carbon sequestration potential due to physiological
features and management practices
Picture: Jens Dauber

3. Research questions
Research on carbon sequestration mainly on
experimental fields, however differences can be
expected in commercial plots
This study is focused on commercial large-scale
Miscanthus fields in south east Ireland, looking at:
• Soil carbon sequestration
• Initial soil carbon loss
• What is influencing the processes?
Picture: Susannah Cass

4. Regional-scale study

5. Materials & Methods
Sampling
Nested sampling design
A number of soil cores taken at three
subplots in a Miscanthus field and an
adjacent control site representing the
former land-use
Cores divided into three depth and bulked
over the sub plot.
Additional cores taken for bulk density

6. Materials & Methods
Analyses
The bulked samples were processed in the
lab and following measurements were
taken:
Total organic carbon
13C/12C stable isotope ratio to determine
the Miscanthus-derived carbon (13C
natural abundance method)
Soil bulk density, particle size distribution,
and pH

7. SOC [Mg ha-1] SOC [Mg ha-1]
-10.00 0.00 10.00 20.00 30.00 40.00 -10.00 0.00 10.00 20.00 30.00 40.00
Control Control
10
10
Miscanthus Miscanthus
Control Control
Depth [cm]
Depth [cm]
20
20
Miscanthus Miscanthus
Control Control
C3-derived carbon
C4-derived carbon
30
30
Miscanthus Miscanthus
Tillage Grassland
After Zimmermann et al., (2012) Global Change Biology Bioenergy, Vol. 4, Issue 4.

8. Field-scale study
Picture: Susannah Cass

11. MG14 TCD_2_1
Average patch area 4.357 m2 3.710 m2
Standard deviation 8.702 25.245
No. Patches 901 1243
Sum of patch area 0.393 ha 0.461 ha
Overall field size 4.390 ha 3.982 ha
Share of field 8.95 % 11.58 %
Zimmermann et al. (in prep.)

12. Farm Area [m2] SD Radius [m] SD
MT3 8.672 6.287 1.519 0.691
MT5 8.151 4.111 1.570 0.372
MT6 10.595 6.028 1.772 0.496
MG11 18.185 14.109 2.233 0.923
MG18 4.329 1.965 1.146 0.264
MG20 10.488 6.335 1.751 0.537

14. MG11
MG18
MG20
Farm
MT3
High MT5
Medium
MT6
Low
-50 -40 -30 -20 -10 0
Difference to area of a non-patch field [%]
Zimmermann et al. (in prep.)

15. Miscanthus-derived carbon [Mg ha-1]
-0.50 0.50 1.50 2.50 -0.50 0.50 1.50 2.50
10 10
20 20
High density
30 Open patch 30
Tillage Grassland
Zimmermann et al. (in prep.)

16. Farm scale

18. High MT6_2
Mean
MT6_1
Low
MT5
MT3
MG20
MG18
MG11
-40 -30 -20 -10 0
Difference in Miscanthus-derived carbon to a no-patch field [%]

19. Conclusions
Measurable soil carbon sequestration even 2 to 3
years after planting Miscanthus
No significant loss of soil organic carbon due to
plantation
High variability between farms
Crop patchiness has significant impact on yield and
soil carbon sequestration

20. Acknowledgements
David Bourke Susannah Cass
Kees-Jan van Groenigen Kate Harte
Bas Boots The Simbiosys Team
Katie Wennig
Catherine Fontana The land-owners for their
Zeno Wong kind permission to work on
Maximilian von Sternburg their lands
Erin Jo Tiedeken
Sarah Kimberley
The EPA for funding the project