Our area is karst, so it's littered with basins, sinkholes and such. It is my hypothesis that some of these areas were water holes for eastern buffalo and thusly places of ambush opportunity.
We have one such geographical 'bowl' which could have been a 10 acre pond a few thousand years ago. We find early archaic blades around it, strictly just around it. The river is about a mile away and we find no debitage between it and this basin. And it's plowed all they way to the river.

So yes, landscapes and climate were possibly entirely different 8,000 years ago.