Roles of differents organisms in shaping the earth's surface?

Question

i need this for my homework plsssss answer

Answer 1

Prairie grass keeps the soil from blowing away, which happened during the dustbowl period because of too many farmers wripping up all the grass to grow more crops.

Beavers build d**n which clreat small lakes and marshes which is used as a habitat for many other species.

Tree roots hold river banks together so they dont get washed down stream and also offer a buffer for dry desert regions (China has a very large tree planting project to slow the expansion of the Gobi Desert  

Coral reefs provide a vital habitat for all kinds of aquatic organisms and some can be seen from space.

Some kinds of algae can kill off entire ecosystems when they bloom, sucking all the oxygen out of the water when they begin to decay and turning large portions of ocean different colors.

HUMANS! We are pumping Carbon Dioxide into the atmosphere and changing the temperature of the entire planet. We d**n up rivers creating massive lakes and stop flooding. We cut down huge swathes of forests to provide ourselves with wood and paper removing a lot of wild habitat. What don't we do to the environment,  we are the biggest thing to hit the earth since photosynthesis.