Rio+20, which no doubt will attract more criticism from the right-wing punditry far in excess of anything that Rio+20 actually means to the world (materially), itself is (IMO rightly) criticized for low goals:

NRDC: At Rio+20, Oceans Protections a Positive Step; More Action Needed

After delegates to the Rio+20 Earth Summit finalized the United Nations text regarding protection of our oceans, Natural Resources Defense Council International Program Director Lisa Speer made the following statement:

“The positive steps contained in the text on plastic pollution, ocean acidification, fishing subsidies and overfishing - if vigorously implemented - will help reverse the decline of our oceans.

“We are exceedingly disappointed that no decision was reached to negotiate a new agreement for the conservation and management of biodiversity beyond national jurisdictions. But the acknowledged urgency for moving forward on this critical biodiversity issue is at least a step forward.”

Here’s one of the hard nuts to crack: we humans draw dotted lines on maps, but the rest of the ecosystem doesn’t work that way. Birds, fish, insects, plant seeds, fungi spores, and so on don’t read human maps.

The toughest thing for our own species to overcome is our tribalism.