song from the forest is about louis sarno, a guy who went to record pygmy music in central african republic and stayed and became part of the bayaka family. the music is sublime. by the end of the film he's stopped recording though and is ending himself, it seems, ill with hepatitis. in a few years he goes back to new jersey to die. and the forest is being destroyed, and soon the bayaka and the sounds of the forest and their hauntingly beautiful music will disappear, and the recordings will be all that's left. 
it's incredibly sad to think about the forest and all the creatures ending.