Sentence:  The reduction of power in a system will necessarily lead to a reduction in levels of articulation, just as depopulation will reduce the number of domains. This reduction can be seen in former provincial-rural centers in the American Midwest and West and in the Argentina pampa. In their most exaggerated form they have been totally deserted, have become "<WSD>ghost towns</WSD>." 
Meaning of the word marked with <WSD> tags:  A town which has become deserted, usually due to failing economic activity, especially one that still has substantial visible remains.