How many planets do we need?
If people around the world live the same life as you, how many planets are needed?
（Access to Ecological footprint Japan website）
You can do right now!-What is “Ecological footprint”?
Ecological footprint is an index showing the environmental capacity of the earth, which shows the load on human beings' environmental impact as an area necessary for resource recycling / purification of waste. It is usually indicated as the area of land and water area per capita necessary to maintain living.(abr from Wikipedia)