Fill in the blanks Human activities have altered many natural environments by . Many lands are now fields where only one from farm crop is grown, an example of a (n) .

Other human activities had added many to the atmosphere some of which cause an ugly Haze called or damage the protective . A consequence of global transportation has been the spread of that outcompete or prey on native species.

Use these to fill in the blank:
Monoculture
Invasive species
Pollutants
Ozone layer
Smog
Deforestation