Question

Desertification occurs when

a semi dry area becomes a desert
a city continues to spread beyond its boarders
a forest is cut down for logging or farming purposes
a desert gets hotter than usual
@AlexandervonHumboldt2

Answer 1

Desertification is a type of land degradation in which a relatively dry land region becomes increasingly arid, typically losing its bodies of water as well as vegetation and wildlife. It is caused by a variety of factors, such as climate change and human activities.

Answer 2

http://en.wikipedia.org/wiki/Desertification