What is an ecological footprint?
An ecological footprint is the amount of biologically productive area required to sustain a person, family, city, etc.
An ecological footprint is the amount of biologically productive area required to sustain a person, family, city, etc. You can calculate and discuss the ecological footprint for an individual or for a nation. It is a concept that can be scaled as needed.
Included in an ecological footprint is everything a given entity, for the sake of clarity let's use individual, needed to produce all of the natural resources that individual consumes. This means the water the person drinks, the land the person lives on, the building materials used for the house or dwelling the person lives in, the food the purpose consumes. An ecological footprint is measured in the amount of biologically productive land needed to sustain that lifestyle.
An ecological footprint is one measure of sustainability. Measures for cities take into account the average per city inhabitant and any resources the city as a whole consumes and provides.
The image below shows the ecological footprints of Barcelona and Cairo in Spain and Egypt respectfully. Note: biocapacity is defined as the productivity of an area.