Where does the energy come from in an
ecosystem?
THE ECOSYSTEM: AN INTER-ACTING COMMUNITY
Every ecosystem is home to a community of plants and animals. All of the
organisms in an ecosystem are continually inter-acting with each other, as well
as with their non-living environment, such as the atmosphere. The study of
these inter-actions is called ecology and scientists who study them are called
ecologists.
An ecosystem depends upon a supply of energy. All living things need energy
for growth, movement and other essential activities. The energy needed by
living things comes from the sun. Every ecosystem depends on green plants to
trap the energy in sunlight and change it into chemical energy. The process by
which green plants convert the sun's energy is called photosynthesis. Green
plants also take minerals, such as nitrates and phosphates, into their bodies
through their roots. These minerals are needed for the healthy growth of the
plants.
In an ecosystem the green plants are called the producers because they are
able to make sugars, which contain chemical energy, using the energy from the
sunlight.
The role of the herbivores in the ecosystem
Some of the animals in an ecosystem gain their energy by feeding on the
producers. These animals are the herbivores. Some herbivores eat the green
leaves of plants and others eat the fruits and seeds. A few herbivores, such as
the elephant and the termite, eat the woody parts of trees and shrubs.
Ecologists call the herbivores the primary consumers because they gain their
energy directly by eating the plants which have trapped and converted the
sun's energy.
The role of the carnivores in the ecosystem
Owl with its prey
The primary consumers are the food of the secondary consumers. These
carnivores are predators which are adapted to catch and kill their prey. The
secondary consumers feed on the bodies of the primary consumers. In this way
energy is transferred from the primary to the secondary consumer.
The Open Door Web Site is non-profit making. Your donations help towards the
cost of maintaining this free service on-line.
Donate to the Open Door Web Site using PayPal