<a href="https://en.wikipedia.org/wiki/Carbon_cycle" class="extiw" title="en:Carbon cycle">en:Carbon cycle</a>-simple diagram
From <a rel="nofollow" class="external free" href="http://www.esd.ornl.gov/iab/iab2-2.htm">http://www.esd.ornl.gov/iab/iab2-2.htm</a>
The original uploader was <a href="https://en.wikipedia.org/wiki/User:Kevin_Saff" class="extiw" title="wikipedia:User:Kevin Saff">Kevin Saff</a> at <a href="https://en.wikipedia.org/wiki/" class="extiw" title="wikipedia:">English Wikipedia</a>.
Transferred from <span class="plainlinks"><a class="external text" href="https://en.wikipedia.org">en.wikipedia</a></span> to Commons.