Hi @caoxiaoran -
The User Guide has an Appendix that gives a few sources for the biophysical table data, as well as several ways of estimating the Z parameter. For Kc and root depth, we do a literature search for studies that have been done in the places we’re working, or places that are similar in land cover and climate. It is definitely a very time-consuming process, even for these simple models.
~ Stacie