Without looking this up further, I take this to mean more than just the physical space a company, communities or individuals take up. A manufacturing company that uses raw materials, for example, may physically occupy X amount of space with its facilities but it also has an impact wherever it gets its raw materials and other goods it uses in manufacturing. In reality, the footprint is larger than one might think. Individuals and communities are the same way. Each of us has an environmental impact far beyond the physical area of our houses or apartments. Think about it.
Indeed, an explanation by R. H. (Dick) Richardson in a course on Natural Resource Management at the University of Texas, Austin, teaches us the following: "Each organism uses resources from the ecosystem to exist. We express this essential requirement as an area of the planet that annually supplies these requirements each year and define this as the organism's ecological footprint. For humans, we can record the consumption data and convert it into an area that supplies these ecosystem resources that are annually appropriated by each person. This is an example of a "systems analysis" that is very helpful for us to understand the connections between our behavior and our dependency on the ecosystem. Our ecological footprint helps appreciate what we get for free from ecosystem services.
Put another way, "the Ecological Footprint of any defined population (from a single individual to a whole city or country) is the area of biologically productive land and water area occupied exclusively to produce the resources consumed and to assimilate the wastes generated by that population, using prevailing technology. As people use resources from all over the world and affect far away places with their wastes, footprints sum up these ecological areas wherever that land and water may be located on the planet."
