Flexi Says: The impact of farming and agriculture can be seen on population density, land transformation, human access, and power infrastructure. Human access and land transformation alter ecosystems and bring in pollution and invasive species, which decrease biodiversity. Land is used for farming and other activities and also for the disposal of hazardous wastes. Much of what has fueled development in agriculture and industry has been the availability of cheap fossil fuels, which pollute the air and emit carbon dioxide into the atmosphere. As the levels of carbon dioxide and other greenhouse gases in the atmosphere rise, they can trap more heat, which causes global temperatures to warm.