The carrying capacity of the earth is measured by its ecological footprint. This tells us how much area of biologically productive land and water an individual, population, or activity requires to produce all the resources it consumes and to absorb the waste it generates, using the prevailing technology and resource management practices.
The unit of measurement is the ‘global hectare’. These are hectares of land (2.471 acres) weighted for productivity as not all pieces of land are equal in what they can provide. So, dividing all the world’s hectares by their total biological productivity in any given year we get an average: the global hectare. Source: http://www.footprintnetwork.org/resources/glossary/#global-hectare-gha
For the planet as a whole, humanity started using more productivity than the planet can provide – i.e. it went into defecit – in 1969. To support the current population, 10bn global hectares of land are required. Humanity is now using twice this – 20bn global hectares according to the Global Footprint Network. Source: http://data.footprintnetwork.org/
According to WWF’s Living Planet Report 2016 [source: http://assets.wwf.org.uk/custom/lpr2016/], humanity currently needs the regenerative capacity of 1.6 Earths to provide the goods and services we use each year.
There were about 12 billion hectares of biologically productive land and water areas on Earth in 2013. Dividing by the number of people alive in that year (7 billion) gives 1.72 global hectares per person.
Per capita Ecological Footprints of several developed countries (e.g. North America, Qatar, Luxembourg, Australia) are as much as six times larger than this. Conversely some of the world’s poorest countries’ are less than half that figure. If everyone in the world were to live in the manner of the richest countries, we would need six Earths like ours.
The biocapacity of ecosystems – in a given hectare of land – to regenerate what people demand – biological materials, absorbing waste material generated by humans – can be improved by the right land management.
The amount we need can be reduced by changing the way we live and reducing consumption.
One Planet Development aims to achieve both of these things.
WWF’s Living Planet Report says: “The Ecological Footprint does not address all environmental pressures and consequences that are related to human consumption, such as pollution and loss of habitat. It provides insight on a minimum condition for sustainability: whether or not human consumption activities fit within the biological threshold defined by the Earth’s biocapacity.”