Unit 3 - The Web of Life in a Forest Ecosystem


Lesson 1: Producers, Consumers & Decomposers


The living elements within a forest ecosystem interact with each other in many complex ways. 
Every organism can be classified in one of three categories: producer, consumer, or decomposer.  Depending on which category they're in, every organism interacts with each other and the forest's resources in a different way. 

In this lesson, we will examine these three categories to understand the interactions between all life in an ecosystem.



The term "producer" is often used for living organisms that produce their own food through photosynthesis.  In simple words, producers are any kind of green plant.  Green plants use the energy of the sun to produce their own food.

Examples of forest producers are trees, shrubs and grasses.



Consumers are another classification of a living organism; they must feed on producers or other consumers in order to survive.  Consumers must ingest food; they cannot produce their own.

Consumers can be herbivores (plant-eaters), carnivores (meat-eaters), insectivores (animal and/or insect eaters), or omnivores (both plant or animal eaters).

Bears and deer are examples of consumers.



Decomposers can be called the "garbage men" of all the living organisms; they feed on dead organisms or the waste from living organisms.

Decomposers take all the dead producers and consumers (plants and animals) and break them down so that plants can use them to make more food.  Decomposers are important because they return nutrients to the soil.

Decomposers, such as bacteria and fungi, break down organic material in order to fuel their own growth and life processes.




     Digging Deeper

      

Did You Know?

Mycorrhiza describes a type of a fungus that grows with the roots of a tree or other kind of plant.Unlike other types of fungi, mycorrhiza is beneficial to plants.

The fungus coats the tree's roots. As the fungus digests organic material in the soil, it releases acids that dissolve minerals in the soil. These minerals are then available to the tree. In return, the tree provides the fungus with the products of photosynthesis.

Many species of trees depend heavily on mycorrhizae. For example, pine trees grow very poorly without the help of mycorrhizae.