TIM ROBARDS
UNIVERSITY OF CALIFORNIA, BERKELEY
CAL. DEPT. OF FORESTRY & FIRE PROTECTION, FIRE & RESOURCES ASSESSMENT PROGRAM
Climate Sensitive Individual Tree Growth Models for the Sierra
Nevada Ecoregion: FVS-WESSIN
Collaborators
Prof. Greg Biging, UC BerkeleyProf. John Battles, UC BerkeleyProf. Kevin O’Hara, UC BerkeleyDr. Martin Ritchie, USDA Forest Service,
PSWMr. Guido Franco, Cal. Energy CommissionDr. Adrian Das, USGSDr. William Stewart, UC Berkeley Extension
Presentation Outline
ObjectivesModel StructureDataModelingResultsImplementation in FVSEvaluationProjections
Objectives
Climate-sensitive forest growth simulator Accurate projections for adaptation and mitigation research Use best available data Six species: PP, SP, IC, DF, WF, RF
Component of bi-annual climate change report Evaluate climate change impacts to forest productivity Mortality
FVS modified variant Use available add-ons (FFE, pests) Take advantage of work already done (volume, imputation) Work with LMS or FVS carbon add-on for carbon projects
General Model Structure
0 1 2 3 4
5 6 7 8
9 10
11
212 13
214
PBAL[ln(GR)] ln(dbh) (dbh) CRln(dbh+1)
PRECIP TEMP SL+ SL[cos(ASP)]
SL[sin(ASP)] SL ln(ELEV+1)
SL ln(ELEV+1) cos(ASP)
SL ln(ELEV+1) sin(ASP) SL ELEV
SL ELEV cos(AS
E b b b b b
b b b b
b b
b
b b
b
215
216 17 18 19
P) SL ELEV sin(ASP)
ELEV ELEV Albrx Albry ik
b
b b b b e e
Data
Fit data
Climate data PRISM Monthly 4x4 km grid
Evaluation data
Data Source
Years Covered (approx.)
No. of Plots
No. of Trees
No. of Diameter Increments
No. of Diameter Remeas.
No. of Height Increments
No. of Height Remeas.
NCStem 1965-1980 105 5,465 4,639 0 2,436 0NCPlot 1961-1998 622 31,807 3,725 39,741 2,991 44,025DolphMC 1958-1988 397 3,232 4,436 284 1,417 150DolphRF 1964-1987 254 1,955 3,564 0 1,296 0
Modeling
Linear mixed effects model Random: temporal, spatial Fixed: everything else
R statistical software LME4 library (Bates 2007) GRID Graphics Equivalence library (Robinson 2007) Bakuzis matrix library (modified from Johnson (2007))
Criteria AIC Parameter significance (topography exception) Residuals
Results: Common Variables
DBH THT
CR PBAL Index
Latitude
Results: Climate & TopographyWinter Precip (10/12)
Winter Temp (10/12)
Many seasonal variables
Climate
Full specification (11/12)
WF height (ELEV)
Topography
Climate VariablesOnly red fir growth entirely negative to temperature increases
More precipitation => more growth
Degree-day variables generally better than straight temperature
Degree Days
Hei
ght G
row
th M
ultip
lier
0.5
1.0
1.5
2.0
2.5
0 100 200 300
Species, Season, Degree CPonderosa pine, w inter, Max 10Ponderosa pine, spring, Max 5Ponderosa pine, summer, Max 10Sugar pine, w inter, Min 10Sugar pine, spring, Min 5Incense-cedar, w inter, Min 5Incense-cedar, spring, Max 5Douglas-fir, spring, Max 5Douglas-fir, summer, Min 10White fir, annual, Max 5Red fir, w inter, Max 10
Height Growth
TopographyStage and Salas (2007) formulation highly adaptable
Requires wide range of data
Requires high tolerance for insignificant parameter estimates
Elevation (feet)
Hei
ght G
row
th M
ultip
lier
0.1
0.2
0.3
0.4
4000 6000 8000
Slope, Aspect0Mid, NMid, EMid, SMid, WSteep, NSteep, ESteep, SSteep, W
Elevation (feet)
Dia
met
er G
row
th M
ultip
lier
2
4
6
8
10
12
2000 3000 4000 5000 6000
Slope, Aspect0Mid, NMid, EMid, SMid, WSteep, NSteep, ESteep, SSteep, W
PP Htgrowth
DF Diam.growth
Implementation in FVS
Source Code from USDA Forest Service, Forest Management Service Center, Ft Collins, CO
Lahey-Fujitsu Express ver. 7.1 Fortran CompilerAdditional input file for climate dataAnnual time steps, maximum of 80Height and diameter growth models for 6 speciesNo changes to outputsYEAR PRE_W PRE_P PRE_S PRE_WP PRE_PS MAXT5D MAXT5D_W MAXT5D_P MAXT5D_S MINT5D_W 1 10600 5739 7640 16339 6503 365 151 92 122 31 2 12189 2801 11030 14990 3904 365 151 92 122 3 12138 1363 4730 13500 1835 365 151 92 122 4 8022 3801 0470 11823 3848 365 151 92 122 31 5 13785 2507 9070 16291 3413 365 151 92 122 31 6 8199 5864 2960 14063 6160 365 151 92 122 31 7 10522 3045 2710 13567 3316 365 151 92 122 31 8 4300 2692 2140 6992 2906 365 151 92 122 9 11346 4333 8900 15679 5223 365 151 92 122 31
Evaluation
Model behavior evaluated using modified and reduced Bakuzis Matrix Forest Types: PP, MC, DF, WF, RF 10 x 10 spacing to 20 years in Conifers (Ritchie 2008) PCT and no PCT Flat ground, NE and SW aspects (30% slope)
Equivalence test using regression method (Robinson 2007)
559 diameter, 167 height measurements ± 25% Reject null hypothesis that model and data different
Douglas-fir, Flat Ground, No PCThe
ight
40
60
80
100
120
140
20 40 60 80 100
Climate Curves
40
60
80
100
120
140
5 10 15 20 25
Height-Dbh
stem
s
100
200
300
400
20 40 60 80 100
Sukachev Effect
qmd
100
200
300
400
5 10 15 20 25
Reineke
age
volu
me
0
5000
10000
15000
20 40 60 80 100
Yield Curves
height
0
5000
10000
15000
40 60 80 100 120 140
Eichorn's Rule
stems
0
5000
10000
15000
100 200 300 400
Yield-Density Effect
Bakuzis Matrix
Leary's Triangular Form, Reduced
version 2.0
LEGENDClimate Scenario
AverageDryColdDryHot
HotWetColdWetHot
Douglas-fir, SW Aspect, No PCThe
ight
50
100
150
20 40 60 80 100
Climate Curves
50
100
150
10 20 30 40
Height-Dbh
stem
s
100
200
300
400
20 40 60 80 100
Sukachev Effect
qmd
100
200
300
400
10 20 30 40
Reineke
age
volu
me
0
5000
10000
15000
20000
25000
20 40 60 80 100
Yield Curves
height
0
5000
10000
15000
20000
25000
50 100 150
Eichorn's Rule
stems
0
5000
10000
15000
20000
25000
100 200 300 400
Yield-Density Effect
Bakuzis Matrix
Leary's Triangular Form, Reduced
version 2.0
LEGENDClimate Scenario
AverageDryColdDryHot
HotWetColdWetHot
Projections
100-year projections Downscaled climate (Scripps Institute, UCSD)
A2: CO2 850ppm max; self-reliance; population increases B1: CO2 550 ppm max; global solutions; population
plateaus 4 GCMs
Elevation transect (Tahoe National Forest) Other models in common area (Shasta County)
Climate sequestration project LaTour State Forest (Southern Cascades) Westcarb
ProjectStatewide Assessment?
Douglas-fir Stand, TNF, A2
Year
Tota
l Cub
ic F
oot V
olum
e pe
r Acr
e
9000
10000
11000
12000
13000
14000
1950 2000 2050 2100
GC ModelPCM1GFDLCRM3CCSMFVSFVSAVG
Douglas-fir Stand, TNF, B1
Year
Tota
l Cub
ic F
oot V
olum
e pe
r Acr
e
9000
10000
11000
12000
13000
14000
1950 2000 2050 2100
GC ModelPCM1GFDLCRM3CCSMFVSFVSAVG
