An official website of the United States government
Here's how you know
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.
Fig. 2. Seasonal variation in net photosynthetic rate (A) and in leaf conductance (B) of Quercus suber, measured in the morning and afternoon, in southern Portugal.