Make a note of which sky you did use and then I would pick a different sky from the Terradome collection and render the image again to see what will happen. Most likely all of the black will be gone. There a one of two sky/light settings from Terradome that do cause this, I don't recall which ones. Whenever I encounter this problem with Terradome, it seems to me that the light is casting shadows from an object that isn't there, perhaps was left behind accidentely by the makers or a wrong setting used.

The other thing that could be going on is that the hills are casting shadows. For the light that casts the shadow , set the to a lower figure, like 0,8 and see that happens then.

If choosing a different sky will get rid of the problem, head over to RDNA and mention the problem. I think I've seen it brought up there before and they may have a solution for you.

Artwork and 3DToons items, create the perfect place for you toon and other figures!

http://www.renderosity.com/mod/bcs/index.php?vendor=23722

Due to the childish TOS changes, I'm not allowed to link to my other products outside of Rendo anymore :(

Food for thought.....
https://www.youtube.com/watch?v=pYZw0dfLmLk