PERD POL Toronto Jan. 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. Gray Natural Resources Canada Atlantic Forestry Centre Fredericton, New Brunswick Sylvie Gauthier Natural Resources Canada Laurentian Forestry Centre Ste. 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 m 3 (approx. 55% of annual harvest) annual loss to spruce budworm = 44 mil m 3 (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 km 2 (100 mil ha) model test area: 9.2 mil ha. Spruce budworm

Dynamic nature of the forest mosaic undisturbed:

Dynamic nature of the forest mosaic harvesting or fire:

Dynamic nature of the forest mosaic SBW disturbed:

Dynamic nature of the forest mosaic the forest landscape: spruce budworm outbreaks

. Variation in spruce budworm outbreak dynamics: time defoliation level defoliation level defoliation level defoliation level

. Variation in fire regime:

climate + years defoliation level Landscape Disturbance Simulation (LADS):

Objective: To include the [somewhat] predictable natural disturbances  insect outbreaks  fire with the [more] predictable forest ecosystem processes  growth  harvesting in long-term simulations of forest dynamics to estimate the effects of a changing climate scenario on biomass production.

fire occurrence and size climate + forest composition spruce budworm outbreak dynamics year 1year 2 year 3 time line:

Necessary elements: SBW impacts on individual species STAMAN SBW recurrence Stand growth model STAMAN

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 species 1 … forest species 16 Canadian Forest Inventory (1992) Canadian Climate Normals (1990)

lat R 2 =.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.

Net annual volume loss:

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. Gray Natural Resources Canada Atlantic Forestry Centre Fredericton, New Brunswick Sylvie Gauthier Natural Resources Canada Laurentian Forestry Centre Ste. Foy, Québec