Optimization of wood production in

Julien Toillon
Emilie Kartner
Bénédicte Rollin
Erwin Dallé
Laurent Roux
Laureline Besdeberc
Romain Leray
Nicolas Marron
Context and objectives
Material and methods
Intensive tree plantations for bioenergy (short rotation coppice, SRC) are
often synonymous with soil depletion. To maintain productivity in the long
term while reducing inputs (water, fertilizer), an optimized matching between:
A network of collaborations and plantations has been
established in France in order to answer practical
questions about SRC itineraries through the study of
eight factors on productivity and water and nitrogen use
efficiencies (WUE* and NUE, respectively), e.g. planting
density, fertilization, N fixing species introduction, etc.
1. plant material characteristics (genera, species, genotypes, mixed or not)
particularly in terms of efficiencies of resource use (especially water and
nitrogen),
- SYLVABIOM: New concepts of sustainable energy crops with
woody species (ANR Bioenergy project, 2009-2012),
The approach taken to meet this objective is to study the effects of the three
categories of above factors on productivity and its determinants through the
study of carbon, nitrogen and water cycles in a network of plantations spread
throughout northern France.
When should we harvest,
spring vs. fall?
Is it relevant to fertilize SRC plantations?
22
4.7
Wood carbon isotope discrimination (‰)
Protocol: Biomass, resprouting, WUE and NUE
estimations in a willow plantation in Kerguéhennec (56)
in fall 2009 and 2010, and spring 2010 and 2011.
0.3
19.2
0.25
4
19
0.2
Objective: Effect of the cultural antecedent (rich vs.
poor) on biomass production and WUE and NUE.
*
0.4
Protocol: Biomass, WUE and NUE estimations
in four willow plantations in French Ardennes (8) differing
by their antecedent, grassland vs. maize cultivation
4.5 0.35
21.4
21.2
4.4
21
4.3
0.3
0.25
20.8
0.2
4.2 0.15
20.6
0.1
4.1
20.4
Wood nitrogen content (%)
Wood carbon isotope discrimination (‰)
19.4
Wood nitrogen content (‰)
4.6
21.6
0.35
19.6
5
0.5
0.45
C
0.05
B
B
A
Unfertiliz ed
Unfertiliz ed
Unfertilized
I214
Koster
20.2
4
Unfertilized
Fertilized
Dorskamp
B
900
C
C
A
Unfertilized
Unfertilized
Unfertilized
I214
Koster
20.5
Tree height (cm)
0
Carbon isotope discrimination (‰)
800
Fertilized
Unfertilized
Miscanthus
Fertilized
Dorskamp
Fertilized
20
700
Miscanthus
600
3
2
1
0
Answer: No. There is no
significant yield and N
content increases
in the poplar
Answer: Despite a constant decrease in N wood content harvest
fertilized plots.
after harvest, there is no clear trend concerning yield and WUE.
Re-growth has to be monitored for a longer period.
A
A
B
C
Fall 2009
Spring 2010
Fall 2010
Spring 2011
18.6
0.1
18.4
0.05
A
B
A
A
Fall 2009
Spring 2010
Fall 2010
Spring 2011
A
B
BC
C
Fall 2009
Spring 2010
Fall 2010
Spring 2011
19
Clump dry mass (kg)
400
300
2
200
100
1.5
18.5
A
C
B
B
Amagne (grassland)
Asfeld (grassland)
Ambly-Fleury (maize)
Semuy (maize)
0
0
18.2
19.5
500
2.5
0.15
18.8
forest
Situation: To avoid concurrence with food
agriculture, SRC plantations will be preferably
installed on marginal, less fertile sites.
Protocol: Biomass, WUE and NUE estimations in a poplar plantation (4
clones) in Estrées-Mons (80) where some of the blocks were fertilized.
21.8
plantation
What is the best
cultural antecedent?
Objectives: Effect of chemical fertilization on biomass production, WUE and NUE,
and comparison with fertilized and unfertilized miscanthus plots.
Objective: Effect of harvest period during the year
on re-growth, WUE and NUE.
6
- Intens&Fix: Ecological intensification of
ecosystems (ANR Systerra project, 2011-2014)
Situation: Bioenergy crops are fertilized, but is it useful to fertilize SRC plantations?
Situation: When harvest is only possible during
the leafy period, leaf exportations are likely to alter
soil fertility.
Clump dry mass (kg)
- CREFF: Cost reduction and efficiency improvement of SRC (ERANet Bioenergy project funded by ADEME and FNR, 2009-2012),
And, 3. soil and climate conditions is to find.
UMR INRA – Nancy University, Forest
Ecology and Ecophysiology (EEF),
54280 Champenoux, France
7
This network is part of three research projects:
2. cultural practices (spraying, densities, pruning, etc.),
A
A
B
B
Amagne (grassland)
Asfeld (grassland)
Ambly-Fleury (maize)
Semuy (maize)
18
17.5
1
Answer: Yield was not linked to the cultural antecedent.
However, willow trees showed a better efficiency to use water
on the poorer sites (grassland antecedent).
0.5
A
A
B
Unfertilized
Unfertilized
I214
Koster
0
Unfertilized
Fertilized
Dorskamp
Is it interesting to variegate
plantations with N fixing species?
Do we have to coppice
at the end of the first year?
Estrées-Mons
Situation: First year coppicing can stimulate the re-growth
during the next year, but it can also affect weak plants when
the first year growth has been poor.
Amagne
Ambly-Fleury Semuy
La brosse
Montceaux
Pleyber-Christ
Objective: Effect of a first year coppicing on biomass
production, re-growth and WUE and NUE.
Lamballe
Saint-Gilles
Kerguéhennec Les Cormiers
Height time course (cm)
29.0
28.0
Tora
Uncoppiced
100
Protocol: Biomass production,
WUE and NUE estimations
in a poplar / black locust
plantation in Saint-Cyr-en-Val (45) with pure and mixed
blocks (alternating rows) of the two species.
Institut National de la Recherche
Agronomique
26.0
Coppiced
Forêt, Cellulose, Bois-construction,
Ameublement
Uncoppiced
Coppiced
Uncoppiced Coppiced
TORA
Uncoppiced
TORHILD
Coppiced
Answer: Yes, but the relevance of a 1st year coppicing depends on the 1st
year growth. Here, coppiced trees were almost as big as uncoppiced trees
after 2 years.
Situation: Sludge spreading in SRC could be
a way to valorize these wastes, but do the trees
need this additional fertilization?
Objective: Effect of a clonal mixing on biomass production,
WUE and NUE.
Protocol: Biomass, resprouting, WUE and NUE estimations
in a poplar plantation in Vatan (36) with pure and mixed
blocks of different clones.
Clone *** - Mixing ns - CxM ns
20.0
Carbon isotope discrimination (‰ )
Tree fresh weight (kg)
Institut pour le Développement
Forestier
Laboratoire des Interactions
Microorganismes Minéraux Matière
Organique dans les Sols
Is there an optimal planting density?
23
600
1500 plants/ha
7500 plants/ha
500
Situation: Mixture of clones and varieties is a way to limit
pathogen development, but what is the effect on biomass
production due to more intense competition?
Clone *** - Mixing ns - CxM **
Chambres d’Agriculture
Is sludge spreading
a relevant practice?
Do we have to use monoclonal
blocks or mixtures of clones?
180
Answer: The mixture of eucalyptus with acacia in Brazil or in
Congo has not shown a clear effect on biomass production. In
Europe, the experiments are in progress.
INTENS&FIX
INGER
Objective: Effect of different quantities of sludge on
biomass production, WUE and NUE.
400
300
200
Clone *** - System *** - CxS ***
0
Bulk leaf carbon isotope discrimination (‰)
18-Nov
4-Oct
3-Nov
19-Oct
4-Sep
19-Sep
6-Jul
5-Aug
21-Jul
20-Aug
6-Jun
21-Jun
22-May
7-Apr
7-May
22-Apr
23-Mar
25.0
Stem height (cm)
50
1500 plants/ha
7500 plants/ha
22
21
20
19
18
Clone *** - System *** - CxS ***
0
110
132
154
176
198
220
242
264
Date (day of the year 2010)
Protocol: Biomass production, resprouting, WUE and NUE
estimations in a willow plantation in Brinon-sur-Sauldre (18)
with sludge inputs or not.
Situation: How does competition
among plants in dense plantations
affect biomass production?
19.8
160
19.6
140
19.4
120
19.2
100
19.0
80
18.8
60
18.2
Pure
Pure
Mixture
18.4
Mixture
18.6
40
20
Echigey
27.0
150
0
Brinon-sur-Sauldre
Association d’Initiatives Locales
pour l’Energie et l’Environnement
Tordis
200
Objective: Effect of mixture
of poplar with black locust
on biomass production,
WUE and NUE.
Sélestat
La ferme du Bouchet
Saint-Cyr-en-Val
Vatan
Clone ***
Coppicing ns
CxC ns
Inger
250
Saint-Sulpice
-des-Landes
Padoux
Attigny
Carbon isotope discrimination (‰)
350
300
Blois
Nouzilly
Guémené-Penfao
Protocol: Biomass, resprouting, WUE and NUE estimations
in a willow plantation (3 clones) in Saint-Sulpice-des-Landes (44)
where a part only has been coppiced at the end of the first year.
400
Le Chesnoy
Gennes sur Seiche
Moyenvic
Champenoux
Darnieulles
La prénessaye
Saint-Ségal
Kerlavic
450
Situation: Mixture of poplar, willow or eucalyptus with N
fixing species (black locust, acacia, alder) can be a way to
improve or to maintain soil fertility in intensive plantations.
Asfeld
18.0
0
Beaupré
Bolaere
Hunnegen
Raspalje
Cima
Luisa Avanzo
Triplo
Beaupré
Bolaere
Hunnegen
Raspalje
Cima
Luisa Avanzo
Answer: Clonal mixture has no significant effect
on biomass production, but it is recommended
to prevent pathogen development.
Triplo
Answer: The experiment is still in
progress. Results are likely to be
dependent on soil fertility: SRC on rich
soils does not need additional nutrient
inputs and elements will probably not be
assimilated by plants and remain on the soil.
Objective: Effect of planting density
(SRC, 1500 vs. very SRC, 7500 trees
/ ha) on productivity, WUE and NUE.
Protocol: Biomass, WUE and NUE
estimations in a 2-year old poplar
plantation in Echigey (21) with
different planting densities.
Answer: After two years,
trees were higher
in the denser plantation.
However, they were more
water-use efficient in the less dense plantation.
Nouveaux concepts de cultures ligneuses durables
pour la production de biomasse à des fins énergétiques
Nouveaux concepts de cultures ligneuses durables
pour la production de biomasse à des fins énergétiques
Plantation network partners:
partners:
Conclusion
Most experiments are still running and conclusions are only preliminary.
However, it appears that it is difficult to generalize because results are
highly dependent on initial soil fertility. Soil richness is indeed a key factor
and SRC technical itineraries as well as plant material have to be adapted
to soil quality in order to maximize the growth potential while avoiding
rapid soil depletion and loss of fertility.
* In the different experiments, intrinsic wateruse efficiency (WUEi, assimilated carbon per
unit of transpired water) is estimated through
its well-known surrogate (Farquhar and
Richards 1984): carbon isotope discrimination
(δ
δ13C, ‰), estimated from wood (panels 1, 2, 3
and 6) or leaves (panels 4 and 8).
Farquhar GD, Richards RA. 1984. Aust. J. Plant Physiol.
11:539-52.
Nouveaux concepts de cultures ligneuses durables
pour la production de biomasse à des fins énergétiques
INTENS&FIX