A good activist or environmental/nature site?

Do anyone knows where I can find some good activist or environmental/nature site? It could be a blog or a social network, if there is any.

thanks

Do a search, I am SURE you will find plenty of them. I know of a few environmental agencies. One I used to hear of a lot was Greenpeace, however I have not heard of them in YEARS. Just do a search, I am SURE you will find plenty.