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.
Pairwise relationships between hardness, pH, and DOC in natural waters occurring across the US (n = 22,076). Green lines represent 5th and 95th percentiles of each parameter. Red lines denote constant-density contours enclosing 905 and 99% of the data based on kernel density estimation (see Supplemental Information for analysis methods). Data from Ryan (Unpublished).
