using simpplle to address questions: has our management altered how a landscape is developing? how...
TRANSCRIPT
Using SIMPPLLE to address questions:Has our management altered how a landscape is developing?How would a landscape have changed without our actions?Can the managed landscape ever return to “historic conditions”
SIMPPLLE*Work was originally done in Feb 04, modifications made to showpotential to address cumulative impacts
Using FRAGSTATS with SIMPPLLE output to provide quantification of landscape patterns.
SIMPPLLE
Three metrics selected for comparison purposes only
Fortine drainage – Kootenai National Forest approximately 25,000 acres
SIMPPLLE
Current landscape is the result of significant level of clearcutharvest systems.
SIMPPLLE
How do Fragstats metrics of the current landscape compare towhat existed prior to harvests
What will be the metrics of a future landscape as a result ofthe harvesting and the continued application of fire suppression?
What are possible values of historic landscapes that includelevels of mountain pine beetle and fire processes?
SIMPPLLE
How different is the future landscape as described by themetrics from possible historic landscapes?
Would the metrics of a future landscape withoutthe harvesting (but with disturbance processes) be different?
Current size class convertedto a grid of 5 acre cells
Very largeMediumOpeningsLargepole
Future size classes from a50 year SIMPPLLE simulationwith harvest (5 acre cells)
Very largeMediumOpeningsLargepole
Preharvest size classes converted to 5 acre cells
Very largeMediumOpeningsLargepole
Preharvest size classes converted to 5 acre cells
Very largeMediumOpeningsLargepole
need to simulate forwardwithout harvest but withexpected natural processes
average mpb in lp - pre harvest conditions
0
500
1000
1500
2000
2500
3000
1 2 3 4 5
decade
ac
res smpb
lmpb
average mpb in lp - current conditions
0
500
1000
1500
2000
2500
3000
1 2 3 4 5
decades
ac
res smpb
lmpb
Simulated mpb activitythat would have occurredwithout harvesting
Simulated mpb activitythat has occurredwith harvesting.
srf average - preharvest conditions
050
100150200250
300350400
450500
1 2 3 4 5
decade
ac
res
average -srf current landscape
0
50
100
150
200
250
300
350
400
450
500
1 2 3 4 5
Simulated stand replacing firewith harvest.
Simulated stand replacing firewithout harvest – but with firesuppression. Modeling of firesuppression may be too effective so ---
srf average - preharvest conditions
050
100150200250
300350400
450500
1 2 3 4 5
decade
ac
res
average -srf current landscape
0
50
100
150
200
250
300
350
400
450
500
1 2 3 4 5
pre-harvest without suppression
0500
1000150020002500300035004000
1 2 3 4 5
decade
acre
w
STAND-REPLACING-FIRE
LIGHT-SEVERITY-FIRE
MIXED-SEVERITY-FIRE
Simulation of fire without suppression showing impactof mpb activity without harvest on the fire processes
Three historic size classesfrom SIMPPLLE simulations
Very largeMediumOpeningsLargepole
Created historic starting with preharvest conditions
FRAGSTATS LANDSCAPE METRIC - SHAPE_RA
0
2
4
6
8
curre
nt
futu
re (5
0 ye
ars)
preh
arve
st
histo
ric -
1
histo
ric -
2
histo
ric -3
ind
ex v
alu
e
The “shape range” metric for the entire landscape of thecurrent and future fall well below that of any simulated historic landscape. The trend from the current to the future is for a continued decrease.
SIMPPLLE
Would need to addwhat the current anda future would be withoutthe past harvest
With harvest
FRAGSTATS CLASS METRICS - OPENINGS SHAPE_RA
01234
curr
ent
futu
re (
50ye
ars)
preh
arve
st
hist
oric
-1
hist
oric
-2
hist
oric
-3
ind
ex v
alu
e
SIMPPLLE
The harvesting created a class metric for “shape range” greaterthan any simulated historic value. However the future trend is for a rapid decrease below any simulated historic value.
With harvestWould need to addwhat the current anda future would be withoutthe past harvest
FRAGSTATS CLASS METRICS - OPENINGS AREA_RA
0200400600800
curr
ent
futu
re (
50ye
ars)
preh
arve
st
hist
oric
-1
hist
oric
-2
hist
oric
-3
ind
ex v
alu
e
SIMPPLLE
The harvesting created a class metric for “area range” greaterthan any simulated historic value. However the future trend is for a rapid decrease below any simulated historic value.
With harvest
Would need to addwhat the current anda future would be withoutthe past harvest