Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
(a, c) Relationship between Ci, Tl, and VPD for poplar (left panels) and loblolly pine (right panels). (b, d) Relationship between Asat, Tl, and gs. Asterisks at the z-axis label indicate overall significance of the model; asterisks at the x- and y-axes indicate significance of the respective parameters (*P < 0.05; **P < 0.01; ***P < 0.001).
