Let's Talk About Ecosystems

An ecosystem is a biological community where plants, animals, and other organisms, interact with each other and their physical environment. Every factor in an ecosystem depends on every other factor, either directly or indirectly. Aquatic ecosystems, coral reefs, deserts, human ecosystem, savanna and rainforests are all examples of ecosystems.

Ecosystems maintain themselves by cycling energy and nutrients. The greatest source of energy for an ecosystem is the sun.

The majority of land-based ecosystems have five tropic levels. What is a trophic level? The trophic level of an organism refers to the position it occupies in a food web. What happens to the energy in an ecosystem?

The amount of energy at each trophic level decreases as it moves through an ecosystem and as little as 10 % of the energy at any trophic level is transferred to the next level. The rest of the energy is released by organisms into the biosphere through metabolic processes as heat. During the process of photosynthesis, light energy is transformed into chemical energy. What happens to the nutrients in an ecosystem?

Nutrients are substances used by animals, plants and other organisms in any ecosystem to survive, grow, reproduce, and decompose.

Nutrients get back into the soil through numerous ways: from decomposed animal waste and dead plants, weathering of rocks and bacteria conversions.

Plants use nutrients such as hydrogen, oxygen, and carbohydrates to produce organic plant material. Animals feed on and digest plant material to fuel growth, reproduction, and movement.

Decomposers play a very important role in the flow of energy through an ecosystem as the help return nutrients in animal waste products and dead animal and plant material to the ecosystem. They break down dead organisms into simpler inorganic materials, making nutrients available to primary producers (plants).

Bacteria, fungi, some insects, and snails are all examples of decomposers.