A few weeks ago, we showed you some of the planet's worst man-made disasters. Now, here are examples of places in which we've effectively helped the environment--or, at least, reversed some of the damage.

Brazil's Atlantic Forest, or Mata Atlantica, is home to 29 critically endangered vertebrates, and holds the world's highest concentration of tree species per acre. Of this precious forest, over 90 percent of the original 330 million acres was torn down.

But thanks to conservation and restoration efforts, 26 percent of the total area has been reforested since November of 1999, according to the Global Restoration Network. Now, many species of formerly endangered birds and mammals, including leopards and pumas, are returning to the region.