MODELLING TECHNIQUES FOR MAPPING IN FOREST INVENTORIESGretchen Moisen, Tracey Frescino

US Forest Service, FIA

Whining from the applications side of the fence

...and not a thoughtto think.

Data, dataeverywhere...

Outline

1. Need for new info2. Data3. Models 4. Maps and applications5. Now what

Need for new information:Traditional reports

• Inventory status and trends in forested ecosystems nationwide

1928 McSweeney-McNary Act

1978 Renewable Resources Act

1998 Farm Bill

• Regional estimates of forest area, tree volume, growth and mortality

Research to develop new products………In addition to estimates of

population totals…….• Make maps! Show how

forest resources are distributed throughout the landscape

• Use those maps: wildlife, fire, harvest….• Automate data retrieval,

visualization, and analysis tools• Build web-based delivery systems• Just do it

Need for new information:Development of an interdisciplinary system

• Dialogue with users, define problems

• Build data base, prepare data

• Build and test models

• Test products in real applications

• Get it out and get feedback

QUESTIONS

FIELD DATA

DIGITAL DATA

MODELS

EVALUATION

DELIVERY

Outline

1. Need for new info

2. Data

3. Models

4. Maps and applications

5. Now what?

DataSix Ecoregions

• Regional diversity• Forested ecoregions• Within state bounds• Sample across all

owners

Data:Plot-level Response Variables

Continuous:• Basal area• Biomass• Crown cover• Growth• QMD• Stand age• TPA• Volume

Catagorical:

• Forest/nonforest class

• Select forest type

Data:

Sample plots

UT1 F: 821 NF: 533

UT2 F: 829 NF: 491

Data: Sample plots MT1 (F: 1277 NF: 294)MT2 (F: 1612 NF: 2108)

Data:

Sample plots

AZ1 F: 712 NF: 135

Process:Many RS-based Predictor Variables

• Raw imagery: TM, MODIS, AVHRR

• NLCD 30 m resolution 19 classes, 8 broad groups

• DEMs: elevation, aspect, slope, hillshade, topographic class

• Spatial coordinates• Other: Soils, TEUs, Precip

Outline

1. Need for new info2. Data3. Models 4. Maps and applications5. Now what?

• Extract data from each layer at each FIA location

• Build a model for each FIA variable

Example: Tree cover ~ f(Cover-type, Elev, Aspect, Slope)

Models:Establishing relationships with predictors

………cover type

……….elevaton

……….aspect

……….slope

to predict

……….crown cover

over unsampled areas

Through the final model, use

Models:Predicting over large areas

ModelsResponse discrete x continuous x interactions

Forest type

Basal area

Biomass

Crown cover

Growth

QMD

Age

TPA

Volume

NLCD

Soils

Elevation

Aspect

Slope

Hillshade

X

Y

X,Y

Elev, Asp, Slope

NLCD(others)

Models:Simple Benchmarks

• Discrete variables

Yhat=NLCD class• Continuous variables

Yhat=mean(Y) w/i

NLCD classes• SIMPLE..is it enough?

Numerous model building tools…..

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iifagf xx mm Raf xx for,)(

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11

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l

kklll wwf jxx

...),,(

),()()(

3

210

m

mm

Kkjiijk

Kjiij

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f

ffaf

xxx

xxxx

GAM

MARS

CART

ANN

Model Test Using Simulated DataCART LM

GAM MARS ANN

X1,…, X10 ~ Unif(0,1)

Y = 2sin(π*X1*X2) +

.4(X3-.5)2 +

.2(X4) + .1(X5)

Residual Plots: BIOTOT in UT2CARTNLCD

GAM MARS ANN

Overview of Analyses

Responses Continuous: BIOTOT,

CRCOV, QMDALL,

STAGE

Discrete: F/NF, F1/F2

Predictors NLCD, AVHRR, topography, UTMs

Technique NLCD, GAM, CART,

MARS, ANN

Evaluation

Criteria

Continuous: RMSE, PWI,

RHO, Runtime

Discrete: PCC, Kappa,

Runtime

Evaluation criteriaModeling Continuous: RMSE, PWI,

RHO, Runtime

Discrete: PCC, Kappa,

Runtime

System Data preparation requirements?

Nest modelling and prediction within a GIS?

User Do the maps help solve real problems?

Can users drive?

Models fuel estimation and EDA as well?

Outline

1. Need for new info

2. Data

3. Models

4. Maps and applications

5. Now what?

Building maps:F/NF, BA, CRCOV, VOL, STAGE, QMD

Fishlake Applications

Build and test large-scale models predicting…- Presense of cavity

nesting birds- Elk calving sites

…using FIA-generated maps of habitat predictor variables

Tom Edwards, Randy Schultz

Applications:Web Delivery

• JPEG preview• PDF map• Build a map (Generate a map based on user-defined criteria)

Tracey Frescino, Frank Spirek

http://www.fs.fed.us/rm/ogden/index.html ► Techniques Research

Warning: These maps are prototypes under development. They are NOT final products

Applications: Interactive Display Environment

• Interactive tool for visualize, summarize, and query resource information

Tracey Frescino

Outline

1. Need for new info

2. Data

3. Models

4. Maps and applications

5. Now what?

Future Work:Refining Interdisciplinary System

• Continue dialogue

• Refined retrieval system

• New predictor variables

• Streamlined modeling box

• NFS test applications

• Refined web-based delivery

QUESTIONS

FIELD DATA

DIGITAL DATA

MODELS

EVALUATION

DELIVERY

Future Work:New Applications

• Prediction for new applications: assessment of resources lost to wildfire or I&D, extension to other

wildlife species

• Improved precision on population estimates

• Improved analyses