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PERD POL 6.1.1 TorontoJan. 23, 2003
Estimating the effects of climate change on large scale natural disturbances, and their impact on biomass productivity in Canada’s boreal forest.
David R. GrayNatural Resources CanadaAtlantic Forestry CentreFredericton, New Brunswick
Sylvie GauthierNatural Resources CanadaLaurentian Forestry CentreSte. Foy, Québec
Biomass as an energy source in Canada:
• provides 6% of Canada’s primary energy
60% increase in the contribution of biomass to Canada’s energy suppy since mid-1970’s
• carbon-dioxide “neutral”
• insect outbreaks and fires account for 82% of the annual depletion of above-ground biomass
• annual insect and disease losses (average) = 100 mil m3
(approx. 55% of annual harvest)
• annual loss to spruce budworm = 44 mil m3
(during peak outbreak)
• annual area burned (average) = 0.6 mil ha(productive forest land)
Biomass losses to natural disturbance agents:
spruce budworm range (Canada)approx. 1 mil km2 (100 mil ha)
model test area: 9.2 mil ha.
Spruce budworm
Dynamic nature of the forest mosaic
Time (yrs)
0 50 100 150 200
Vo
lum
e (
m3
/ha
)
0
20
40
60
80
undisturbed:
Time (yrs)
0 50 100 150 200
Vo
lum
e (
m3
/ha
)
0
20
40
60
80
Dynamic nature of the forest mosaicharvesting or fire:
Time (yrs)
0 50 100 150 200
Vol
ume
(m3/
ha)
0
20
40
60
80
Dynamic nature of the forest mosaicSBW disturbed:
Dynamic nature of the forest mosaic
Time (yrs)
0 50 100 150 200
Vo
lum
e (
m3
/ha
)
0
20
40
60
80
Time (yrs)
0 50 100 150 200
Vol
ume
(m3/
ha)
0
10
20
30
40
50
60
70
Time (yrs)
0 50 100 150 200
Vol
ume
(m3/
ha)
0
10
20
30
40
50
60
70
the forest landscape:
Time (yrs)
0 50 100 150 200
Vol
ume
(m3/
ha)
0
10
20
30
40
50
60
70
Time (yrs)
0 50 100 150 200
Vo
lum
e (
m3
/ha
)
0
20
40
60
80
Time (yrs)
0 50 100 150 200
Vo
lum
e (
m3
/ha
)
0
20
40
60
80
Time (yrs)
0 50 100 150 200
Vo
lum
e (
m3
/ha
)
0
20
40
60
80
time (t0+years)0 50 100 150 200 250
popu
latio
n le
vel
spruce budworm outbreaks
.
Variation in spruce budworm outbreak dynamics:
time
timetime
time time
defo
liat
ion
leve
lde
foli
atio
nle
vel
defo
liat
ion
leve
lde
foli
atio
nle
vel
.
Variation in fire regime:
climate +
Time (yrs)
0 50 100 150 200
Vol
ume
(m3/
ha)
0
20
40
60
80
years
defo
liat
ion
leve
l
1 25
+ + . . .
Landscape Disturbance Simulation (LADS):
Objective:To include the [somewhat] predictable natural disturbances
insect outbreaksfire
with the [more] predictable forest ecosystem processesgrowthharvesting
in long-term simulations of forest dynamics to estimate the effects of a changing climate scenario on biomass production.
fire occurrenceand size
climate+
forest composition
spruce budwormoutbreak dynamics
year 1year 2
year 3
time line:
Necessary elements:
SBW impacts on individual speciesSTAMAN
SBW recurrence
time (t0+years)0 50 100 150 200 250
popu
latio
n le
vel
Stand growth modelSTAMAN
Time (yrs)
0 50 100 150 200
Vol
ume
(m3/
ha)
0
20
40
60
80
Time (yrs)
0 50 100 150 200
Vol
ume
(m3/
ha)
0
20
40
60
80
Necessary elements (con’t):
•historical records of spruce budworm outbreaks;
•historical records of fire.
Data – SBW outbreaks:
response variables:• timing of outbreak initiation• duration• severity• variability
explanatory variables:• latitude• longitude • combination of lat. & long.• summer temperatures• winter temperatures• annual precipitation• growing season VPD• forest species1
• …• forest species16
Canadian Forest Inventory (1992)Canadian Climate Normals (1990)
1960 - 1998
axis #1
axis
#2
+lag
dur sevvar .GDM .
WDM.
PREC.
VPD.
bF
.
bS
.r/wSyB
oBs/bM
oM wP.
jP
.rPH
C
tAoP
lat
R2 = .59
Relationships: SBW outbreaks - environment:
Data – fire occurrence:
explanatory variables:• latitude• longitude • combination of lat. & long.• summer temperature• monthly average mid-day
relative humidity• monthly average mid-day
wind speed• monthly mean precipitation
Canadian Climate Normals (1990)
raw data (CanFI cells):• no. fires/yr.• average fire size • average month of fire• day of cumulative 50% fire occurrence
Large Fire Database
response variable for fire zone:• no. fires/yr. (x ± s.d.)• average fire size (x ± s.d.) • average month of fire (x ± s.d.)• day of cumulative 50% fire occurrence (x ± s.d.)
a raster based simulation model;
C++ programming language;
stand-level growth and yield;
sustainable harvest levels;
natural disturbances (spruce budworm & fire);
insecticide protection;
fire management.
LADS (Landscape Disturbance Simulator):
Harvesting rates:regulated by current growing stock.
Harvesting sites:determined by stand maturity, salvage opportunity, mill requirements.
Insecticide protection program:site selections dependent on anticipated volume loss;total size of program set by user
LADS (Landscape Disturbance Simulator):
Landscape description:9.2 mil ha, 400 ha cells
Stand harvesting priorities:age (older before younger);softwood:hardwood ratio (2:1 desired);level of defoliation (more severely defoliated cells
before less severely defoliated ones);protection (exclude protected cells).
LADS (Landscape Disturbance Simulator):
LADS is climate dependent
•CGCM2 (GHG+A) model from the Canadian Centre for Climate Modelling and Analysis.
•climate variables interpolated by thin-plate splining to same resolution as CanFI data.
year
0 50 100 150 200 250 300
-20
0
20
40
60
80
softwoodhardwood
volu
me
(m3 x
106 )
(pro
tect
ed -
unp
rote
cted
)
Net annual volume loss:
N
EW
S
5000 - 10000
10000 - 1500015000 - 20000
20000 - 2500025000 - 30000
30000 - 3500035000 - 40000
> 40000
0 - 5000
Water
tonnes
Total carbon loss (no protection, std. climate, 300 yr simulation):
tonnes
Total carbon loss (no protection, modified climate, 300 yr simulation):
Thank you.LADS (Landscape Disturbance Simulator)
Estimating the effects of climate change on large scale natural disturbances, and their impact on biomass productivity in Canada’s boreal forest.
David R. GrayNatural Resources CanadaAtlantic Forestry CentreFredericton, New Brunswick
Sylvie GauthierNatural Resources CanadaLaurentian Forestry CentreSte. Foy, Québec
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