Environment and Ecology

Environmental Challenges

What is zero population growth?

Zero population growth, or ZPG, is the estimation of the birth rate necessary to maintain the size of the human population at its current level. As of now, the rate is estimated as 2.1, which means that each set of existing parents would need to have (on average) slightly more than two children during their lifetime. The extra 0.1 allows for infant mortality.


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