Each driver has a characteristic spatial and temporal scale at which it affects ecosystem services and human well-being. Climate change may operate on a spatial scale of a large region; political change may operate at the scale of a nation or a municipal district.
Amazon has several competitors in the electronics and general merchandise segment, many of which are brick and mortar rivals including Best Buy, Family Dollar, RadioShack, Staples, Target, Walmart, Sears, Big Lots, Delia and Systemacs.
The service, perceived as a direct rival to Google's Gmail, marks a new front in the ongoing and increasingly bitter battle between Facebook and Google to gain the loyalty of users. 1  Bitter battle: Mark Zuckerberg unveils Facebook's new messaging service in San Francisco. Seen as a direct rival to Google's Gmail, it integrates all web and text-based communications and works instantaneously.