In what ways did native peoples transform north americab environment before european colonization?

While the stamp of Native Americans on the landscape is certainly less than that of the Euro-American colonization, they certainly did leave their mark on the earth. 

1. Homes - Whether a home was built as a permanent structure or with nomadic tendencies in mind, resources were put to use in their building. The oldest known permanent dwelling in North America is at Sky City, New Mexico. It was built by the Acoma tribe, which is now split into Acoma/Laguna. 

2. Agriculture - Growing and harvesting plants requires fertile soil to be cultivated. This would require a certain amount of clearing land. 

3. Trails - Nomadic tribes would have created trails they traveled at certain times of the year. Permanent homes would require travel routes whether for water, food or trade. These trails would not compare to the roads we know today, but there would be well traveled areas in abundance. 

4. Tools- Native Americans used many types of tools. These tools might not have required a foundry to smelt metals, but none the less there are thousands of tool artifacts that have been found all over North America. With these tools, natives shaped the landscape around them.