Carolyn N. Kinder
All living things can be found on or near the surface of the Earth. Accept for the sun’s energy, all their needs are supplied by the small proportion of the Earth’s resources contained in thin layers on the Earth. If the water, oxygen and other elements vital for life were only used once, they would soon run out. This is why many of nature’s processes work in cycles. There is a constant exchange of the elements between air, earth, water, plants and animals. These recycling processes ensure that all living things are able to live and grow.
1
Carbon is constantly circulating in many different forms through living things, the soil and the atmosphere.
The sun provides light, warmth, food and oxygen. Green plants use solar energy to make food from carbon dioxide and water. As the plants do this, they release oxygen to the environment.
The green plants use the food themselves and, in turn, nourish many other living organisms, including man. The energy from food is really chemical energy produced from solar energy by plants.
Carbon dioxide in the atmosphere plays an important role in warming the Earth by trapping the sun’s heat, in what is called the greenhouse effect. The burning of fossil fuels has greatly increased the amount of carbon dioxide in the atmosphere.
2
The future effects of this buildup on global temperatures can only be guessed at. Nature’s cycles are relatively stable. Any changes that do occur take place within certain limits. Although there may be minor variations, the cycles continue and life goes on. Man’s activities are fundamentally changing the environment and disturbing cycles in nature. See figure 2.
(figure available in print form)
Figure 1:
Reprinted by permission from
Exploring The Water World
, 1991: Regional Water Authority Education Programs.
(figure available in print form)
Figure 2:
Carbon is constantly circulating in many different forms through living things, the soil and the atmosphere.