Ecosystem

An Ecosystem is a smaller part of a Biome

An Ecosystem (ecological system) is a small part of a Biome (and of the Biosphere). Using a rough analogy, think of an ecosystem as a building block of a Biome; just like a human cell is a building block of an organ. And as cells need the body to survive, ecosystems need the Biosphere.

Bog ecosystem. Mer Bleu, Ottawa. Photo: National Capital Commission / Commission de la capitale nationale

We define an ecosystem as an area in which organisms relate to their environment in similar ways. Ecosystems studies focus on how plants and animals produce and consume energy, food chains, inputs from the sun, flows of carbon etc. Two ecosystems may have similar plants and animals, but with different relative numbers and relationships.

Most of us are familiar with the ecosystems in which we live. Rural people may know their ecosystems better than urban people. But even in the middle of a city, we know the types of trees that grow well, the animals that eat their seeds, and the birds that nest in them. We may also know which soils support local foods.

Changes in ecosystems are fairly easy to see. But those changes may bother us less than changes in Biomes (tropical forest, tundra etc.), for two reasons:

  • ecosystems are small, with less long-term stability than Biomes;
  • human activities have modified some ecosystems so much, we may not know what they should be like in their natural state.

We may not understand how ecosystem changes relate to Biome changes. Yet ecosystems are still excellent places to monitor environmental change

Water Rangers testing water. Photo: Cassidy Swanston

We may not understand how ecosystem changes relate to changes in Biomes, or to changes in the Biosphere. Yet ecosystems are still excellent places to monitor environmental change. For example, Water Rangers produce water testing kits. Volunteers use these to monitor changes in lakes, rivers and coastal waters, and send the information back to Water Rangers. This is then assembled into an open-data platform for researchers (and anyone else interested). This data can be used to quickly indicate changes in the aquatic parts of many ecosystems. (https://waterrangers.ca)

Coral. Photo: Francesco Ungaro on Pexels

Monitoring of ecosystem change can be linked to changes in the Biosphere, through science. For example, amateurs and scientists are studying changes in Coral Reef Ecosystems in relation to climate change – a phenomenon occurring across the Biosphere.

Here is a brief explanation:

  • Coral is an organism that lives in sea water. Within a certain temperature range it secretes calcium carbonate that creates ridges in shallow water. Corals build on top of each other, and ridges grow to the ocean surface. There the pounding waves prevent further growth upward. Coral ridges grow in circles called reefs. These semi-enclosed areas provide a stable environment for other plants and animals (e.g. fish) to exist. They are called Coral Reef Ecosystems and they have existed for a long time.
  • Increasing ocean water temperature is reducing the ability of coral to grow. It can even kill them. Yet coral are the foundation of the Coral Reef Ecosystem. So their death threatens other plants and animals in that ecosystem. But solving the problem is beyond local control. Climate change is increasing ocean temperatures. Death of the coral is an indicator of changes at the level of the Biome and Biosphere.

There are many cases, however, where correction of an ecosystem problem is within local control. For example, in rural areas people can reduce the amount of silt clogging a river by maintaining trees on slopes along the river. The trees prevent the runoff of soil into the river.

In urban areas there is a similar problem, of silt clogging a river, caused by runoff from paved areas to storm sewers. The storm sewers carry the water to the river. People can reduce this problem with simple changes such as:

  • using rain barrels to catch water flowing off the roofs of buildings,
  • installing permeable paving on laneways, so that storm water will soak into the ground instead of flowing directly to rivers.

One of the biggest ways we can reduce stress on ecosystems is to create sustainable cities

One of the biggest ways we can reduce stress on ecosystems is to create sustainable cities. It will reduce the environmental impacts of the cities and allow natural processes to work better.

Creating a culture of sustainability in a city will make it easier to make the city sustainable. This culture will focus people on human activities that may harm ecosystems. Simple methods, such as the Biosphere Eco-City, can connect people to take action. This engagement can simultaneously address ecosystem problems, and motivate stakeholders to make their cities sustainable.

We can help ecosystems by understanding them and reducing pressure on them. This will help Biomes and the Biosphere.