(July 14, 2015) Unless humans slow the destruction of Earth's declining supply of plant life, civilization like it is now may become completely unsustainable, according to a paper published recently by University of Georgia researchers in the Proceedings of the National Academy of Sciences.
"You can think of the Earth like a battery that has been charged very slowly over billions of years," said the study's lead author, John Schramski, an associate professor in UGA's College of Engineering. "The sun's energy is stored in plants and fossil fuels, but humans are draining energy much faster than it can be replenished."
Earth was once a barren landscape devoid of life, he explained, and it was only after billions of years that simple organisms evolved the ability to transform the sun's light into energy. This eventually led to an explosion of plant and animal life that bathed the planet with lush forests and extraordinarily diverse ecosystems.
The study's calculations are grounded in the fundamental principles of thermodynamics, a branch of physics concerned with the relationship between heat and mechanical energy. Chemical energy is stored in plants, or biomass, which is used for food and fuel, but which is also destroyed to make room for agriculture and expanding cities.