What is an Ecosystem and How Does It Work?
A very basic knowledge of what is an ecosystem is required of students enrolled in environmental science. Although the word ecosystem is commonly encountered, still, many students do not know exactly what is an ecosystem. This article explains in easily understandable terms the concepts and principles that will enable students to describe what is an ecosystem in its rudiments.
This simplified explanation of what is an ecosystem will provide even the non-environmental science major an understanding of what is an ecosystem and how it works including man's role in maintaining its integrity. A greater understanding of what is an ecosystem will help towards its preservation and sustenance thus sustain life in the planet.
What is an Ecosystem?
What is an ecosystem? The word “ecosystem” is derived from the Greek terms “oikos” and “sistema”. Oikos means habitat. Sistema means a set of interacting components arranged neatly to work together for some purpose. Essentially, an ecosystem is a habitat made up of living and non-living things that work harmoniously together to produce energy and eventually attain sustainability. The arrangement of the ecosystem is like a clock where each part works closely and in harmony with each other such that it is able to tell time.
The simplified ecosystem can be represented by the following illustration:
Illustration by P. Regoniel
For an ecosystem to exist and continue its function, plant and animal life must be present. And for plants and animals to survive, energy from the sun in the form of light is needed to sustain the whole ecosystem. Plants use the energy from the sun to jump start the transfer of energy between and among living organisms. Plants synthesize food for the whole ecosystem through the process of photosynthesis.
Photosynthesis in the Ecosystem
Photosynthesis is derived from the Greek word “phos” which means “light” and “synthesis” which refers to the process of producing a chemical compound. The chemical compound produced by plants is starch or a complex sugar (C6 H12 O6) that stores energy. Animals, particularly the herbivores and omnivores (eats both plant and animal material), consume this chemical compound by eating plant leaves, fruits, seeds, roots or other edible parts.
Consumption in the Ecosystem
Not all animals can consume plants so herbivores do it for them. Herbivores are animals that are adapted to eat plants. When herbivores eat plants, the energy stored in the complex sugar produced by plants provides the herbivore the energy to go on with its activities and live. Those activities include walking, finding a mate, reproducing itself, and of course escape its predators. Some of the material eaten by the herbivore are not consumed or metabolized by the animal to produce energy. These are stored in the herbivore’s body to enable it to grow and keep for future uses.
Carnivores on the other hand are animals that are adapted to eat meat. They need to eat other animals to survive. The animals they consume may be an herbivore or another carnivore. As the carnivore consumes another animal, matter and energy derived from it again becomes a part of the carnivore. So in the process of consumption and being consumed, matter and energy is transferred from one living thing to another until a top level predator ends the transfer.
Cycling of Materials and Energy in the Ecosystem
The processes in the ecosystem, however, could not be completed without the cycling of materials and energy synthesized by the plants. This is the reason why animals, as well as plants, die. When animals and plants die, they become once again organic matter through the action of decomposers. Decomposers are those small organisms that act on non-living organic material to break it down into simpler components – the nutrients. Nutrients once again become available for plants to use and repeat the whole cycle again.
Man’s Role in the Ecosystem
Man is also entwined in the whole ecosystem as man’s survival is dependent on the processes of the ecosystem primarily deriving energy from plants to sustain life. But since man has found ways to synthesize his own food without necessarily getting involved in the normal consumption patterns in an ecosystem, there is a tendency for the ecosystem to be upset. Too much consumption of plants or animals or destroying any of the components that make up the ecosystem leaves the ecosystem with virtually nothing to cycle and recycle to keep it stable. The normal cycling of nutrients may be interrupted and the ecosystem loses its balance. Once the normal cycling patterns in an ecosystem is lost, man's very survival is threatened.