Nearly three-quarters of people live in countries without enough natural resources to live sustainably – and without enough money to buy them from elsewhere.
Biocapacity is the ability of an ecosystem to regenerate the resources that people use. It compares the rate at which we use our natural resources against our ability to replace them and absorb our waste materials.
To maintain its population, a country needs either enough resources to match its people’s ecological footprint and maintain a biocapacity surplus, or it needs enough money to buy the necessary biocapacity from elsewhere to make up any shortfall.
Mathis Wackernagel at Global Footprint Network in California and his colleagues looked at the biocapacity of every nation for the years between 1980 and 2017, examining whether they had a deficit or surplus of resources. Then they compared these with each country’s GDP per capita – the sum of all monetary transactions in an economy split between the nation’s population – to estimate average income.
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In 2017, 72 per cent of the global population lived in countries with a biocapacity deficit and below-average income. This means 5.4 billion people couldn’t sustainably get the ecological resources they need and were unable to buy them from other nations.
“If you have less than average income, you cannot bid as strongly on foreign markets for things as much as other countries,” says Wackernagel.
The researchers ran this calculation for every year from 1980 to 2017. The situation as it stood in 1980 suggests that in that year, 57 per cent of the world’s population lived in below-average-income countries with a biocapacity deficit.
The research also revealed, perhaps unsurprisingly, that nations with higher incomes were able to function with a much more severe local biocapacity deficit because of their ability to buy biocapacity from elsewhere. The strength of a country’s economy determines how many resources it is able to buy and use, says Wackernagel.
There are some nations where average income is high and where there is a biocapacity surplus, including Sweden, Canada and Finland. There are also wealthy countries that are in severe biocapacity deficit, such as France, Germany and Japan.
Although 2017 was the most recent year for which information was available to make the calculation, there were some changes to the climate impact in 2020 because of the covid-19 pandemic. Preliminary findings show that the demand on biological resources for all people combined exceeded the amount that Earth’s ecosystems produce by 56 per cent in early 2020.
“But it looks like demand for resources is back up to similar levels as before the covid-19 pandemic,” says Wackernagel; in 2017, global demand exceeded Earth’s resources by 73 per cent.
Journal reference: Nature Sustainability, DOI: 10.1038/s41893-021-00708-4