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.
Net photosynthetic rate (A), transpiration rate (B), water use efficiency (C) and leaf water content (D) in Ulmus pumila seedlings at different times after sand burial. Values are means ± s.e., n = 8.