Interactions<span> between the </span>human<span> social system and (the “rest” of) the ecosystem</span>
Australia
this isn't needed>20 word thing
Answer:
As the river erodes the landscape in the upper course, it winds and bends to avoid areas of hard rock. This creates interlocking spurs, which look a bit like the interlocking parts of a zip. When a river runs over alternating layers of hard and soft rock, rapids and waterfalls may form.