It affects the river flow, because since all of those trees are cut down, <span>there's nothing to hold the soil in place. And then, because of that, river banks will erode then causing the river to form a different shape. And when the river forms a different shape, it can cause the river pattern to change
~Hope this helped :)</span>
<span>B. they needed access to bodies of water for trade
Water and aquatic access was necessary for water as well as access to trade.
Hope this helps :)</span>
The answer is seafloor spreading
