Ecological Footprint:
- The ecological footprint is a measure of human demand on the Earth’s ecosystems.
- It is a standardized measure of demand for natural capital that may be contrasted with the planet’s ecological capacity to regenerate.
- The Ecological Footprint is rooted in the fact that all renewable resources come from the earth.
- It accounts for the flows of energy and matter to and from any defined economy and converts these into the corresponding land/water area required for nature to support these flows.
- The Ecological Footprint is defined as “the area of productive land and water ecosystems required to produce the resources that the population consumes and assimilate the wastes that the population produces, wherever on Earth the land and water is located.”
- It compares actual throughput of renewable resources relative to what is annually renewed. Non-renewable resources are not assessed, as by definition their use is not sustainable.
- The total “footprint” for a designated population’s activities is measured in terms of ‘global hectares.’ A global hectare (acre) is one hectare (2.47 acres) of biologically productive space with an annual productivity equal to the world average.
- Currently, the biosphere has approximately 11.2 billion hectares of biologically productive space corresponding to roughly one quarter of the planet’s surface.
- These biologically productive hectares include 2.3 billion hectares of ocean and inland water and 8.8 billion hectares of land.
- The land space is composed of 1.5 billion hectares of cropland, 3.5 billion hectares of grazing land, 3.6 billion hectares of forest land, and 0.2 billion hectares of built-up land.
- These surfaces represent the sum total of biologically productive hectares we rely on for our survival. They represent the earth’s natural capital, and their annual yield represents our annual natural capital income.