CogKnoSys

Knowledge you can walk. Read the idea below, then step up to the general, across to peers or down to the specific.

Physical

Ecosystems

An ecosystem is a community of living things interacting with their non-living surroundings, linked by flows of energy and nutrients.

Learn, discuss, create, buy or invest

The idea

An ecosystem is made of living things, like plants, animals and microbes, together with the non-living parts of their environment, like soil, water and climate. These parts are linked by the movement of energy and nutrients. A pond, a forest or a coral reef can each be studied as an ecosystem. Biomes, such as deserts or grasslands, are broader groups of similar ecosystems, although the line between the two ideas is not sharp.

Energy enters most ecosystems when plants use sunlight to grow through photosynthesis. Animals move that energy and matter along by eating plants and one another. When living things die, decomposers break down the dead material and return nutrients to a form that plants and microbes can use again.

Ecosystems are always changing. Storms, fires and other disturbances knock them off balance, and they slowly recover. An ecosystem's ability to absorb a shock and still keep working is called its resilience. People depend on ecosystems for food, water, fuel and building materials, and for services such as clean air and the pollination of crops.

Check yourself

Question 1 of 2

What is an ecosystem's ability to absorb a disturbance and keep working called?

Pick one. The first pick counts.

Composition

what it's made of

  • Living parts — Plants, animals, fungi and microbes, which scientists call biotic factors.
  • Non-living parts — Soil, water, air and climate, called abiotic factors.
  • Energy flow — Energy enters through photosynthesis and moves on as animals eat plants and each other.
  • Nutrient cycling — Decomposers break down dead matter so nutrients can be used again.

Connection

how it relates

Under Earth Systems

Related

  1. Energy Formsstrength 70 of 100

    Plants capture the energy of sunlight and turn it into chemical energy that the rest of the ecosystem runs on.

  2. Lower Columbia Ecosystems and Wildlifestrength 60 of 100

    The wetlands, rivers and forests of this region are real-world examples of ecosystems at work.

Felt

  1. Nature Connectionstrength 50 of 100

    Spending time in healthy ecosystems is one way people come to feel connected to nature.

Change

how and why it evolves

Past
The word ecosystem was first used in 1935, in a publication by the British ecologist Arthur Tansley. Arthur Roy Clapham had come up with the word at Tansley's request. In 1963 the Hubbard Brook Ecosystem Study began in the White Mountains of New Hampshire, the first successful attempt to study a whole watershed as an ecosystem.
Now
Many ecosystems are being damaged by human impacts, including pollution, soil loss, habitat fragmentation and invasive species.
Next
Restoring damaged ecosystems is seen as one way to help reach the Sustainable Development Goals, though how much can be restored is uncertain.

Knowledge you can walk. Read the idea, then step up, across or down.

Ecosystems

An ecosystem is a community of living things interacting with their non-living surroundings, linked by flows of energy and nutrients.

Learn, discuss, create, buy or invest

The idea

An ecosystem is made of living things, like plants, animals and microbes, together with the non-living parts of their environment, like soil, water and climate. These parts are linked by the movement of energy and nutrients. A pond, a forest or a coral reef can each be studied as an ecosystem. Biomes, such as deserts or grasslands, are broader groups of similar ecosystems, although the line between the two ideas is not sharp.

Energy enters most ecosystems when plants use sunlight to grow through photosynthesis. Animals move that energy and matter along by eating plants and one another. When living things die, decomposers break down the dead material and return nutrients to a form that plants and microbes can use again.

Ecosystems are always changing. Storms, fires and other disturbances knock them off balance, and they slowly recover. An ecosystem's ability to absorb a shock and still keep working is called its resilience. People depend on ecosystems for food, water, fuel and building materials, and for services such as clean air and the pollination of crops.

Check yourself

2 quick questions, instant feedback.