Sentinel Landscapes

Bogor 30/09-01/10/11

Long-term monitoring of tropical logged

forests

Alain Billand, with Sylvie Gourlet-Fleury and Plinio Sist

Cirad

Research Unit « Tropical forest goods and services »

A network of evergreen forest plots,

involving Amazonia, Africa and South

East Asia

Réalisation G. Cornu

Sentinel Landscapes

Bogor 30/09-01/10/11

N. Fauvet CIRAD-Forêt 1999 Source : Unasylva, FAO

Equateur

Tropique du Cancer

Tropique du Capricorne

Paracou (Cirad,

French Guiana)

Oyan (Iraf, Gabon)

A network of research sites

in natural tropical forests

Mopri, Téné, Irobo

(Idefor, Ivory Coast)

MBaïki (Icra, MEFCP, RCA)

STREK (Inhutani I, MF, Indonesia)

BULUNGAN (Inhutani II, MF, Indonesia

ZF2 (Inpa, Brazil)

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Bogor 30/09-01/10/11

Ecology : prediction of changes in structure,

floristic composition and genetic diversity

Inter-action between ecology and economy :

To determine the modalities and intensity of

logging compatible with the long-term supply

of timber

Prediction of changes in biomass: To take

account of climate change in logging norms

and standards : optimize carbon DD

(mitigation), design forest norms adapted to

expected CC (adaptation)

General objectives :

Similar protocols : initial untouched forests, controled logging, variable intensities, and untouched control plots

Photo F. Bouchet-Lannat

Sentinel Landscapes

Bogor 30/09-01/10/11

Tools

Genetics, Molecular tools

(PCR-RFLP, RAPD,

microsatellites …)

ADN

chloroplastique

ADN

nucléaire

Models and simulation

platforms

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26

Years

Nu

mb

er

of

tre

es

>=

60

cm

db

h (

/ha

)

SB (observed)

StoMat(1)

StoMat(2)

Angélique and

near neighbors

Experimental sites:

surveys, databases, GIS,

soils, water, light, T°

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Bogor 30/09-01/10/11

Experimental designs

Area surveyed annually or every two years: 94 ha (+ 25 ha) : ~ 73 000 trees

3 types of silvicultural treatments

Area surveyed annually : 40 ha : ~ 23 000 trees

2 types of silvicultural treatments

N

Paracou (1984 -Cirad)

Mbaïki (1982 - ICRA, MEFCP, AFD, Cirad)

Sentinel Landscapes

Bogor 30/09-01/10/11

Experimental designs

STREK (1989-1997)

RKL 1:

6 plots 4 ha each

Post-logging silviculture (15 years)

RKL4:

12 plots 4 ha each

6 Plots with RIL (2 MDC50cm, 3 MDC

60 cm)

Every tree dbh 10 cm

BULUNGAN (1997-Present)

2 Blocks ~100 ha each

1 Block with RIL

1 block with CNV

In Each Block: 12 plots, 3 control, 1

ha each

Logging intensity varying from low

(< 6); medium (6-9) and high (9

trees/ha)

Every tree dbh 20 cm

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Bogor 30/09-01/10/11

Modelling tools

Types of models

Distribution based models (Usher matrices)

• Density-dependent: Paracou (Favrichon 1995), Mbaïki, STREK (Favrichon &

Young-Cheol, 1998, Sist & al., 2004)

• Density-independent: Paracou (Gourlet-Fleury & al., 2004), Mbaïki (in prep.)

Single tree models

• Distance dependent: Paracou (Gourlet-Fleury, 1997)

• Distance independent (gap): Paracou (Picard, 1999)

Softwares

CAPSIS (http://capsis.free.fr), object-oriented environment developed by INRA,

hosting various forest dynamics and stand growth and yield models. Hosts Selva,

a tree-based distance dependent model developed by Cirad

StoMat, user-friendly software which runs density-independent matrix models

Sentinel Landscapes

Bogor 30/09-01/10/11

In Indonesia: do RIL techniques lower the level of damages in the stand? Are results from Bulungan coherent with results from STREK?

Some results : monitoring logging damages

y = 4,5x + 3,8

0

10

20

30

40

50

60

70

80

3 4 5 6 7 8 9 10 11 12 13

% o

f tr

ee d

am

ag

ed

y = 1,9x - 2,0

0

5

10

15

20

25

30

3 4 5 6 7 8 9 10 11 12 13

% c

an

op

y o

pen

ing

Felling intensity (n/ha)

Canopy opening

Damages to trees BULUNGAN

48.4 % 30.5 %

48.8 % 34.6 %

0

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30

35

CNV EFI

0

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35

CNV RIL

% o

f o

rig

ina

l tr

ee p

op

ula

tio

n

Felling

Skidding

STREK

BULUNGAN

Skidding Felling

In mixed dipterocarp forests, the capacity of RIL to

reduce damage to the stand is limited by logging

intensity (N> 8 trees/ha)

Sentinel Landscapes

Bogor 30/09-01/10/11

In Indonesia: how does logging impact the dynamics parameters of stand and group of species? Results from STREK (RKL4)

Impact of logging on forest dynamics

3,7

1,6 1,6

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1,3 1,5

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2 4 Years after logging

mort

alit

y %

/yr

G2: 70-80 % (8/ha)

G1: 80 % (6/ha)

G3: <70% (14/ha)

G0

Mortality

0

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2 4Years after logging

cm

/year

Diameter increment

S1: pioneers, eg Macaranga spp.,

Anthocephalus chinensis

S2: Dipterocarps except Vatica

S3: other species 0

5

10

15

20

25

30

35

Pioneers Dipt. Others Total

n/ha

/yea

r

Recruitment

Sources: Nguyen-Thé et al. 1998, Sist & Nguyen-thé 2002

Sentinel Landscapes

Bogor 30/09-01/10/11

In Indonesia: can we give recommendations in order to achieve sustainable timber management? (Simulations with a density dependent matrix model)

Modeling felling cycles

Stationary harvested volume, 3rd cycle:

35 m3/ha (G1)

41 m3/ha (G2

36 m3/ha (G3)

MEAN STANDING COMMERCIAL VOLUME

UNDER A 35 YEAR CYCLE REGIME

0

50

100

150

200

0 35 70 105 140 175 210 245 280 315 350 385

Years

m3/h

aG1

G2

G3

Harvested volume at 1rst cycle:

44 m3/ha (G1, 6 trees/ha)

78 m3/ha (G2, 8 trees/ha)

130 m3/ha (G3, 14 trees/ha)

Source: Sist et al. 2003

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Bogor 30/09-01/10/11

1999 2299 (300 yrs)

2599 (600 yrs) 2899 (900 yrs)

Modelling long term tree regeneration and dissimination

F. Guyana, Angélique/main commercial specie

Sentinel Landscapes

Bogor 30/09-01/10/11

Predict sustainability of timber yields

N. Fauvet CIRAD-Forêt 1999 Source : Unasylva, FAO

Equateur

Tropique du Cancer

Tropique du Capricorne

Harvested volume at 1rst cycle (/ha): 20 m3

Max. 13% of timber volume recovered, low long-term recovery

rates and high uncertainties

Mbaïki

1980 2000 2020 2040 2060 2080 2100

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2.0

Year

Num

ber

of

trees

80 c

m d

bh (

ha

1)

Felling cycle: 30 years

Time needed to recover trees ≥ 80 cm dbh: at least 100 years

Lobaye (Central African Republic) – Entandrophragma cylindricum (Picard et al.,

2008, Gourlet-Fleury et al., unpublished results)

Sentinel Landscapes

Bogor 30/09-01/10/11 Source: Gourlet-Fleury et al. 2005

Monitor impact of logging on tree genetics In French Guiana: is the present felling regime (all trees 60 cm dbh, every

40 years) sustainable for the first commercial species (Dicorynia guianensis)? (Simulations with a tree-based distance dependent model, Selva)

Allelic richness

3

4

5

6

7

8

27 111

195

279

363

447

531

615

699

783

867

Années

Ao

Exploité

Non exploité

0,5

0,55

0,6

0,65

0,7

27 111

195

279

363

447

531

615

699

783

867

Années

H d

e N

ei

Exploité

Non exploité

Diversity (H de Nei)

Genetic diversity

viewpoint

Demographic

viewpoint

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Années

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ec

tif

>=

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h

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Années

Eff

ec

tif

>=

60

cm

db

h

Sentinel Landscapes

Bogor 30/09-01/10/11 Source: Sist et al. 2003

Balance logging intensity v/s logging cycle

In Indonesia: what would be the shortest sustainable felling cycle for a given logging intensity?

Shortest felling cycle and corresponding mean annual volume:

27 years, 1.6 m3/ha (G1)

41 years, 1.8 m3/ha (G2)

89 years, 1.4 m3/ha (G3)

0

20

40

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Logging intensity n/ha

rota

tion

len

gth

(years

) tsust = 10,2 e0,162*LI

On a mean basis, a logging intensity of 8 stems/ha would yield 67m3/ha

every 42 years = 1,6 m3/ha/an and should be recommended

Sentinel Landscapes

Bogor 30/09-01/10/11 Source: Gourlet-Fleury et al. 2004

Recovery of trees/species after logging In French Guiana: how does the commercial timber stock of species recover

after logging? Can silvicultural treatments fasten the recovery? How will the floristic composition evolve?

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1984/1986 1989/1991 1991/1993 1993/1995 1995/1997 1997/1999 1999/2001 2001/2003

Périodes

DD

(cm

/an

)

∆D0

∆D1

∆D2

∆D3

Espèces principales (58 EGE)

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Années

Eff

ecti

f re

cru

té (

/ha)

T0 T1 T2 T3

Diameter increment

Recruitment

Stock recovery

Sentinel Landscapes

Bogor 30/09-01/10/11

The number of exploitable trees (4 trees/ha, 66 m3/ha) cannot be recovered

within 40 years (around 75% could, less than 70% within 30 years). Thinning

the stands should allow it

In Republic of Central Africa (simulations with a density independent matrix model, StoMat)

Recovery of forests stands

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Années

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rfac

e te

rriè

re >

= 1

0 c

m d

bh

(m2

/ha)

Témoins

Exploitées

Exp./éclaircies

A serious problem will occur with Entandrophragma cylindricum (Sapelli) and

Triplochiton scleroxylon (Ayous). Resp. 15% and 42% recovered within 30 years

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1,80

1984 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39

Year

Nu

mb

er

of t

ree

s >

= 8

0 c

m d

bh

(/h

a)

Logged (observed)

Mean (predicted)

Entandrophragma cylindricum (Mbaïki) - Logging intensity 90%

Sapelli Mbaïki (>= 10 cm)

0,0

1,0

2,0

3,0

4,0

5,0

6,0

7,0

0 2 4 6 8 10 12

Nombre de cycles (30 ans)

Eff

ecti

f to

tal >= 1

0 c

m d

bh

(/h

a)

Entandrophragma cylindricum ( Mbaïki). Logging intensity

90%

0,0

0,2

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1,2

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0 2 4 6 8 10 12

Number of felling cycles (30 years)

Nu

mb

er

of t

ree

s >

= 8

0 c

m d

bh

(/h

a)

Sentinel Landscapes

Bogor 30/09-01/10/11

The role of large trees

Large trees play a major part in stocks loss, but also

recovery

Example in Para (Brazil, Cikel Verde)

Mazzei de Freitas et al. (2010)

Trees ≥ 60 cm dbh = 30% of standing

volume

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Bogor 30/09-01/10/11

Recovery of carbon stocks

Carbon stocks recover, but dynamics similar to

commercial stocks => felling cycles too short

Blanc et al. (2009)

12 years 50 years

Paracou (French Guiana)

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Bogor 30/09-01/10/11

New/Recent initiatives in Central Africa

Coforchange (5y, mid

term):

4000 y forest/climate history

4.5 million ha of forest

inventories /300 sp

Edaphic conditions (soil,

water, temperature, etc.)

Improve logging norms

Dynafor (just starting)

A range of new large scale

plots (2 x 400 ha)

Sampling diversity of Congo

Basin forests

Involvement of logging

companies

Design small scale research

activities in concessions

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Bogor 30/09-01/10/11

New logging practices, better adapted to

forest ecology : Number of exploitable trees,

Duration of felling Cycle (cf Fr Guyana 30-

>60 y)

Measure impact of reduced impact logging

Promote sylviculture/ Thinning (shortening of

felling cycles by 10 to 20y)

Maintenance/protection of genetic pools

Special attention on selected logged species

(fragile, endanged, rare, endemic, etc.)

Compensation through REDD+ ?

Some results : support to decision-making,

design of tools , laws, norms

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Bogor 30/09-01/10/11

Scale of plots

PSP are essential:

We need some « heavy » PSP to benefit from long-term data series and quantify trends

We also need many lighter PSP in order to quantify the variability of the dynamics parameters and to adapt models to local conditions

A need to undertake a detailed compared analysis of results issued from existing PSP: this could help identify general trends in the reaction of populations and stands to the disturbances linked to logging

Better use of simple or complex models to make predictions

Complex and detailed models remain essential to explore long-term scenarios and identify critical thresholds

Photo J.-G. Jourget

Sentinel Landscapes

Bogor 30/09-01/10/11

Feasibility

Choice of sites: decisive, needs careful, long

sampling based on state of the art data

Partnerships : (i) South : research with and by

national researchers + training from Bsc to PHd (ii)

North :networking, merging/optimising costs.

Public/private sectors, administrations, NGOs,

communities…

Funding and permanence issues : the constant

nightmare. Juggling with tiny bits. Diverting permanent funds… Financial

capacities : Developing v/s emerging countries

No research question with single sci. disciplin (ecology,

etc.) Always mix questions : ecology and economy,

ecology and sociology, etc.