Rio+20: Bottle sculptures on the beach highlight sea pollution

The Rio+20 U.N. sustainability conference in Brazil ends today, after three days of talks involving delegates from nearly 200 countries.

It's all but certain that much of the meetings consisted of the kind of slow-moving, diplomatic conversations that may impact global policy in the long term, but don't often resonate with the public.

But a few miles away from the conference halls, an installation on Botafogo beach packs a serious punch.

Three enormous fish burst from the sand, but instead of scales, the sculptures are constructed using thousands of discarded PET (polyethylene terephthalate) plastic bottles.

Spotlights illuminate the sculptures, which are meant to draw attention to the growing amount of plastic waste in the sea. A sign nearby, bearing the official Rio+20 logo, reads "recycle your attitudes" in Portuguese.

A 2009 study by Scripps scientists found plastic garbage concentration in the ocean has increased 100-fold in the past 40 years, and may constitute up to 90 percent of trash in the ocean.

The artist behind the installation is currently unknown.