Are you talking about the Roman Empire or the city of Rome?
The city still exists and was never completely abandoned but having its population drop from 1 million to less than 50000 is a significant change. I guess, if you consider this change a "collapse" depends if you think it dropped fast enough.
How much the fall of the (western) Roman Empire was due to or was accelerated by environmental factors is still up to debate. Was the migration period caused by climate changes? Or what role did the deforestation of the Italian peninsula play?
The city still exists and was never completely abandoned but having its population drop from 1 million to less than 50000 is a significant change. I guess, if you consider this change a "collapse" depends if you think it dropped fast enough.
How much the fall of the (western) Roman Empire was due to or was accelerated by environmental factors is still up to debate. Was the migration period caused by climate changes? Or what role did the deforestation of the Italian peninsula play?