What Plants Do
DB: This is Earth and Sky, with a question from a listener. She asks, “What would happen if all the plants disappeared?”
JB: Well, for starters, Earth would be much quieter. Almost all living creatures on our planet depend on plants for food and oxygen, either directly or indirectly. So if all the plants disappeared, eventually so would almost all the other life.
DB: Also, Earth would be hotter. Plants take carbon dioxide out of the atmosphere. If it weren’t for plants, there’d be an increase in the levels of this greenhouse gas – and Earth’s temperature would climb.
JB: Then, too, plants play a role in Earth’s water cycle. They absorb rain and snowfall – and eventually release much of this moisture back into the atmosphere. Without plants, the patterns of precipitation would likely be altered. What’s more, since plants cover much of Earth’s land surface, they decrease the amount of light that our planet reflects back into space. Without plants, Earth would reflect more light – and this would change climate patterns, too.
DB: Finally, plants anchor Earth’s soil. If the plants were gone, soil would be washed from Earth’s surface on a grand scale. So without plants, Earth would be hot – barren – and maybe muddy. To ask your science question, come to earthsky.org. Thanks today to the U.S. Fish and Wildlife Service and to the National Fish and Wildlife Foundation – supporting the conservation of native fish, wildlife, plants and their habitats. We’re Block and Byrd for Earth and Sky.
The following person was interviewed for today’s program. Our thanks to:
Dr. William W. Adams III
Department of Environmental, Population, and Organismic Biology
University of Colorado
Boulder, CO
Additional Teacher Resources
University of Illinois Extension: The Great Plant Escape
This site provides a great resource for elementary age students for understanding the important role that plants play in our lives. The site is set up with an interdisciplinary design to introduce students to plant science and increase their understanding of how plants grow.
Oracle, ThinkQuest, Education Foundation: Plants
Plant life has existed on the Earth for hundreds of millions of years?longer than humans have been around. In fact, many believe that plants made the Earth’s atmosphere livable for humans and animals by changing carbon dioxide into the oxygen that we all breathe. It’s no wonder that plants are still intertwined with the survival of humans and other animals today. This site explains exactly how we are intertwined and gives several examples of human dependence on plants.
