To explain what ecological footprint is, we must first give a definition for an ecosystem: An ecosystem is a biological environment consisting of all the organisms living in a particular area, as well as all the nonliving, physical components of the environment with which the organisms interact, such as air, soil, water, and sunlight.
So the ecological footprint is a measure of human demand on the Earth’s ecosystems. It compares human demand with the planet’s ecological capacity to regenerate. It represents the amount of biologically productive land and sea area needed to regenerate the resources humanity consumes and to absorb and render harmless the corresponding waste.
Using the eco footprint we can estimate how much of the Earth (or how many planet Earths) it would take to support humanity if everybody lived a given lifestyle. For 2006, humanity's total ecological footprint was estimated at 1.4 planet Earths – in other words, humanity uses ecological services 1.4 times as fast as Earth can renew them.
Humanity is living beyond the limits, we consume more than what nature can provide. And as a result biodiversity (the variation of life forms on the planet) is being squeezed out of existence with greater and greater pressure with each passing year.
While I was doing this presentation I did an eco footprint quiz. Here are my results: If everyone in the world lived the same way I do we would need1.86 Earths