The location of the study lakes by lake class.

<p>The study area is Michigan USA and the map shows the regions used in all analyses (Ecological Drainage Units) delineated by brown lines within state boundaries delineated by grey lines. The 346 lakes are shown by lake hydrologic class (DR_ST are drainage lakes with stream inflows; DR_ST-LK are drainage lakes with stream inflows and at least one upstream lake ≥ 10 ha, see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0135454#pone.0135454.g002" target="_blank">Fig 2</a> for details). The regions are labeled with a three-digit code as in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0135454#pone.0135454.t001" target="_blank">Table 1</a>. The inset shows the location of Michigan within North America.