It seems every summer there is more and more media coverage of ocean dead zones, those regions of our seas that become so polluted with algae that grow on fertilizer run-off that there's no oxygen left for other species. This summer the dead zone in the Gulf of Mexico was predicted to be the largest one yet, although it didn't quite break the record.
This blog post from the Huffington Post gives a little deeper analysis of why dead zones and why the story won't go away, at least until we put serious effort into changing agricultural production practices.