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.
Overview of URL microbial diversity based on the 15 most abundant organisms in each sample, classified mostly at the phylum/class level. Samples are listed in order of increasing the distance between the sampling site and the closest access tunnel to seek evidence of perturbation due to the presence of the tunnel. (a) 7 Mizunami 0.2 µm-filter URL samples collected between 2014 and 2015. (b) 18 Horonobe URL 0.2 µm-filter samples collected between 2013 and 2016
