What is an Ecosystem?

Ecosystem versus Biome

An ecosystem is a dynamic entity made of a biological community and the physical and chemical factors that make up its non-living or abiotic environment. Ecosytems are made of a group of interacting, interrelated parts that form a whole. All ecosystems are considered "open" systems because energy and matter are constantly being transferred in and out. There are many different ecosystems: the Everglades, coral reefs and ponds, bat caves, grasslands and deserts. Climate differences from place to place usually determine the types of ecosystems. Differences in terrestrial ecosystems are influenced mainly by the dominant vegetation. A biome describes a major or dominant vegetation type such as tropical rain forest, grassland, tundra, etc., that extends over a large geographic area. It is never used to describe aquatic systems, such as ponds or coral reefs. A biome is also broader than an ecosystem.

Parts of an Ecosystem

All ecosystems are made of biotic and abiotic components. Abiotic or non-living factors include: temperature, soil or water chemistry, sun, water or moisture and precipitation. Biotic or living components include herbivores, carnivores, omnivores, primary producers, and detritivores. These environmental factors perform specific functions or jobs in each ecosystem. Since an ecosystem is a dynamic system, all factors will vary over space and time.

The Food Chain

Everything is connected to everything else in a food chain. Although biological systems are much more complicated, and consist of many food links and chains, a basic food chain helps to explain the major links in any food web.

In a food chain, energy from the sun is captured by plant photosynthesis and flows from one tropic level to another tropic level of the chain. A trophic level is composed of organisms that make a living in the same way; they are all plants, herbivores or carnivores.Herbivores get their energy by eating plants or plant products, carnivores eat herbivores, and detritivores consume waste products and help decompose materials.

Waste products are produced at all levels. Scavengers, detritivores, and decomposers like bettles, crows and catfish eat waste products but microbes finish the job of decomposition.

There are many types of food chains within an ecosystem. A rain forest floor or a woodland stream in a forested area, a salt marsh, or an ocean floor in very deep areas where all sunlight is extinguished 1000’s of meters above.

This post is part of the series: All About Ecosystems

In this series of articles, you will learn all about ecosystems-what they are, what types exist, and how they differ from one another.