I was reading up on this brief Wikipedia article on the subject and have a following question:

I would like to know what other means were used to achieve similar effect. The only instance I know now is the Korean DMZ, in which case the means are purely diplomatic and "agreed" upon. Buffer zones however do not seem to meet similar criteria Romans were going after. Carthage was not to be a buffer zone as there was nothing to buffer from (to my understanding). If so, what means were used? Other chemicals, reforesting, deforesting, cutting access to water? Also, why?