23rd April 2024
Bio capacity is a measure of the ability of an ecosystem to support human life (a somewhat biased use of the term bio meaning life!) It measures the amount of food, fuel, water etc that the area of land can produce to support human life and the amount of waste – sewage, pollution etc – that it can safely absorb.
It reflects the regenerative capacity of ecosystem – how quickly, and by how much, can renewable resources be replaced. How quickly can crops be harvested and regrown to provide food? How quickly can trees be felled and regrown to provide timber? How quickly can fish stocks be replenished after the fish have been caught and eaten? How quickly can sewage be treated and returned into the system as drinking water? How much pollution can the air absorb before it becomes harmful to human life?
Bio capacity is measured in global hectares (gha) – ie land area per person. The global hectare is a land area that averages out land across the globe taking into account land that is more productive and land that is less productive. It measures how many hectares are needed to support one person.
The Green Tau 