Question

how do rivers affect the biodiversity of an area?

Answer 1

They reduce water and sediment flows to downstream habitat ,  and change the nature of the river's estuary where many of the world's fish species spawn the impact from dams increase the vulnerability of entire ecosystems to other threats such as climate change.

Answer 2

Rivers affect biodiversity of an area

as we human being throw waste

on land which gets washed into water bodies,

and the aquatic animals mistake plastic bags for food and eat them.

This has caused the death of many aquatic animals.

As to say 95 % of we human beings affect biodiversity and 5 % by nature .