Mason Earles' presentation to the Davis R Users' Group on R and FVS

1. R and the Forest Vegetation Simulator
Interfacing an old school model with R
MASON EARLES
D-RUG 02.13.13

2. What’s the forest vegetation simulator (FVS)?
What did I want to do with it?
Where does R fit in?

3. What’s FVS?
Models forest growth, mortality and fire

4. What’s FVS?
- Developed and commonly
used by US Forest Service
- FORTRAN language
- Empirically based
growth/mortality
- Individual trees modeled
- Tree interactions affect growth
and mortality

5. My goal: Use FVS ‘Monte Carlo style’ with
stochastic fire and drought events
Problem: I don’t know the FORTRAN language;
FVS is a mess of code maintained by a couple of
people

6. But I know R!

7. Open-FVS = publicly available source
code…API linking FVS to R

8. FVS can now be run from R!

9. A few things I’ve done with linked R + FVS

10. Batch modify keyword code files w/ R
Keyword file 

11. Stochastic fire events
Burn probability = 40 years

12. %dopar% for parallel simulations

13. Stochastic drought events
Similar approach for drought events

14. Simulation
Examples:
#runs = 100