Other Implementations

Several other versions of the 3-PG model have been developed over time. Below are some examples:

📊 Excel

The Excel implementation of 3-PG was written in Visual Basic for Applications, and works as an add-in for an Excel document. It’s primary purpose was to facilitate the use of 3-PG in a research setting, as the flexibility provided allows for testing species adaptation to novel climates, and parameterizing new species. The Excel model can be downloaded here, and an extensive user guide can be found here. In addition to the original Excel version, 3-PG_mix was developed in an attempt to model mixed stands. More on this implementation can be found here.

Tip

The 3-PG Excel version has excellent documentation - it is a great way to start exploring the power of 3-PG and playing around with different parameters!

🧮 r3PG

The r3PG package is an R package written by Volodymyr Trotsiuk, Florian Hartig, and David I. Forrester. The package is available on GitHub here, with a accompanying documentation here. The package is described in detail here¹. This package is particularly useful for investigating different site parameters and species due to the ease of visualizing output variables, however it is limited over large areas.

Footnotes

1. Trotsiuk, V., Hartig, F., & Forrester, D. I. (2020). r3PG–An r package for simulating forest growth using the 3‐PG process‐based model. Methods in Ecology and Evolution, 11(11), 1470-1475.