Image from BBC
On this World Ocean Day, I'm taking another look at a phenomenon of global import that still has yet to gain much traction in environmental -- let alone mainstream -- news publications: ocean acidification. I've already covered this subject at length here at TreeHugger over the last few months (see links at the bottom of this post and TH's voluminous archive), but I just ran across a Nature article that provides a vivid description of what ocean acidification could well look like within the next few centuries, if not decades.
A team of British scientists, led by Jason Hall-Spencer from the University of Plymouth, surveyed a group of CO2-bubbling volcanic vents in the Mediterranean Sea to investigate the effects of acidified water on marine organisms. The pH of the seawater around the vents was around 7.8 - 7.9 -- the normal pH of seawater is 8.1 -- and dropped down to 7.4 in some places. The results were stark: No corals were present, mollusks were seen with their shells dissolving (none were present in area with a pH of 7.4) and calcifying algae (those that form calcium carbonate skeletons) were often displaced by non-calcifying species like seagrasses, which benefited from the extra carbon dioxide. Overall, the number of species present near the vents was 30 percent lower when compared to neighboring areas.
As recounted in the Nature story, these findings could portend ominously for coral reef ecosystems around the world:
The results could have far-reaching implications, Hall-Spencer warns. For example, coral reefs prevent coastal erosion in many areas, and some microbes are key to marine ecosystems. The survey also found that, in the absence of these organisms, alien species of algae overran the surrounding environment. "I'm quite worried that [the algae] are going to radically change the marine shallow habitats around the planet," he says.
Even if we were to slash global emissions production tomorrow, we probably wouldn't be able to avert some of the worst impacts of acidification. Of course, that doesn't mean that we shouldn't do anything. Learning more about acidification and other phenomena affecting our oceans, helping organizations like Oceana (which has a great list of tips for World Ocean Day) that are doing some great work and, most importantly, spreading the word are just a few of the things we can all do to help.
Via ::BBC News: Natural lab shows sea's acid path (news website)
More on Ocean acidification
::Some (Phytoplankton) Like it Acidic
::Increasingly Acidified Waters Could Prompt Mass Shellfish Dissolution