Human activities have impacted the environment more than any other species, including deforestation, natural resource depletion, reduced biodiversity, and pollution of the air, land and water. Humans have been impacting the environment for thousands of years; however, since the industrial revolution in the 1800s, the impact has drastically increased due to increased population, industrial manufacturing and agricultural practices.
As the human population has grown, the need for more land has caused an increase in the cutting down of forest lands for habitation and farming. The result has been an increase in soil erosion, an increase in species extinction from habitat loss, and a reduction of oxygen supplied by the trees, as well as lower amounts of carbon dioxide being removed from the atmosphere.
Much of the land that has been cleared is used for agriculture to feed Earth's growing population. To increase output farmers have turned to chemical fertilizers and defoliants that pollute the soil and watersheds. Increased production of limited types of crops and livestock for food has reduced the amount of different plant and animal species on the planet.
Industrial and personal use of fossil fuels has dramatically increased the amount of air pollution in the atmosphere while systematically using up the supply of the non-renewable resources such as coal, oil and natural gas.