1. Characterizing trends in forest site productivity using high-resolution climate products
Western Mensurationists Meeting 2016
Jarred Saralecos – University of Montana, Graduate Research Assistant
Advised by – David Affleck and Zack Holden

2. Summary Motivations Methods Analysis Questions Projected Results
Motivations Methods Projected Results Next Steps
Summary
Motivations
Demand for site productivity estimates, landscape scale approaches
Methods
Data distribution, downscaled climate product, modeling approach
Analysis Questions
Modeling aims and challenges
Projected Results
Evaluating site index projections from multiple perspectives
Next Steps
Exploring management impacts of fine-scale productivity

3. Vegetation Management in Complex Terrain
Motivations Methods Projected Results Next Steps
Vegetation Management in Complex Terrain
Fine-scale gradients drive large variation in vegetation dynamics
There is a challenge in determining the proper tools and data to make informed decisions about:
What to plant where
How fast it will grow

4. Motivations Methods Projected Results Next Steps
WDNR is seeking a means of estimating forest productivity across their ownership
Easily obtained and cost effective
Defined by usable metric
Works over time and large landscapes X X X

5. Measures of Productivity
Motivations Methods Projected Results Next Steps
Measures of Productivity
Empirical: Site Index
Based on Ht:Age relationships
Time consuming, not always available
Species specific
Resolution based on sample density
Process-based: Net Primary Productivity (NPP)
gC/m2/yr
Conversion of atmospheric carbon into organic compounds
Mostly used at continental or global scales
Output not in an actionable form for land managers

6. Motivations Methods Projected Results Next Steps
Study Area

7. Site Tree Data WDNR Forest Resource Inventory System (FRIS) 1991-2013
Motivations Methods Projected Results Next Steps
Site Tree Data
WDNR Forest Resource Inventory System (FRIS)
Northern Idaho and Western Montana FIA

8. Scaling Climate in Mountainous Terrain
Motivations Methods Projected Results Next Steps
Scaling Climate in Mountainous Terrain
Mountains create steep biophysical gradients
Daily, gridded 250m climate data, 1979-present
Radiation
Minimum temperature
Maximum temperature
Atmospheric humidity
Precipitation (Prism)
Holden and Jolly, 2011

9. Modeling Site Productivity
Motivations Methods Projected Results Next Steps
Modeling Site Productivity
Topographic
Aspect, Elevation, and Slope
Climatic
Moisture Availability, Radiation, Temperature
Integrated climate (Physiological Processes Predicting Growth – 3PG)
Landsberg and Waring, 1998
NPP
Remote sensing
Vegetation indices - NDVI (Landsat)

10. Modeling Site Productivity
Motivations Methods Projected Results Next Steps
Modeling Site Productivity
Develop relationships between site characteristics and site index
Evaluate assumptions and limitations for each approach
Apply best fit equations across study area
Validation with a subset of the data
Explore the sensitivity of site index to change in climate predictors 50 60 70 80 90
100
110
120
130
140
150
160
Mean Annual NPP (gC-1m-1)
Site Index50

11. Analysis Questions Motivations Methods Projected Results Next Steps
How do contrasting modeling approaches vary in predicting site index?
What climate factors drive site index predictions and do they vary across species and region?
How sensitive are productivity predictions to perturbations in climate?

12. Projected Outcomes Motivations Methods Projected Results Next Steps
Topographic approach limited over large areas
Climatic approach driven by a sites growth limiting characteristic
NPP will provide a more consistent predictor across landscape
Vegetation indices (NDVI) limited by status of individual forest stands during period of interest

13. Next Steps Assimilate climate products for 3PG
Motivations Methods Projected Results Next Steps
Next Steps
Assimilate climate products for 3PG
Complete model selection & calibration
Explore management impacts: planting, stand biomass accumulation, site quality effect on SDI

14. Potential Management Impacts
Motivations Methods Projected Results Next Steps
Potential Management Impacts
Regardless of current state, determine most effective species for a given site
Dynamic stand growth
accounting for varying productivity in-stand
Changes in site productivity under changing climatic conditions

15. Motivations Methods Projected Results Next Steps
Questions?