Erosion commonly occurs following conversion of natural vegetation to agricultural land – carrying away fertile soil as well as fertilizers, pesticides and other agrochemicals.
Use more renewable resources (solar, wind, hydroelectric, etc) and fewer fossil fuels (coal, petroleum, and natural gas), since fossil fuels produce a lot of carbon dioxide
Eat less livestock (farm animals, such as cows, produce a lot of methane and waste) and possibly become vegetarian/vegan
Decrease deforestation (trees absorb carbon dioxide and release oxygen)
Recycle/reuse more items to decrease the amount of trash in oceans, forests, and other ecosystems
