Life on Earth - Abiotic Factors..."Say What Are They?"
A complete study of Earth's ecosystems includes learning about the non-living environment in which living things exist. The non-living parts of an organism's environment are called abiotic factors. Examples of abiotic factors include such things as air currents, temperature, moisture, light, and soil type.
Abiotic factors have large effects on living things and often determine which species of organisms will survive in a given area. For example, a lack of rainfall in an area will only allow drought tolerant plants and animals to survive. Continued drought would reduce the total amount of plant matter in the area, which would then reduce the number of plant-eating animals that could survive in the area.
Step outside and list all of the abiotic (non-living) things that make up the environment you are in. List at least ten things. Next to each item on your list, tell what would happen to you if that item either didn't exist or changed drastically. Now compare your list with a similar list compiled by a friend, or classmate. What items did you find were on both lists? What abiotic items were found on only one list?
Look at the photograph of Cathedral Valley, Utah to the right. Using the same paper you prepared with the list of abiotic factors, describe the abiotic differences between where you live and Cathedral Valley.
Now observe the image of a Hawaiian volcano at the right. Abiotic factors limit the kinds of organisms that will survive in an environment. What is the most important limiting factor in this photo?
The picture at the left shows a stream of water flowing away from a hot spring in Yellowstone National Park. The colors are caused by different organisms living in the water. The variations you observe are due to how these organisms grow differently based on slight changes in water temperature within the stream.
The photo to the right was taken looking at a hot spring in Yellowstone National Park. As you look closely, you observe a mat of microorganisms growing in very hot water. In the center of the photo tiny flies come to eat algae from a bump that rises high enough above the stream flow to cool the water a degree or two. Drag your mouse over the image if you need to have the flies pointed out to you!
Find a photograph of an environment on Earth that you think looks cool. You may use a book, magazine, or the Internet as a reference. Identify all the abiotic factors you can. (Click the link for a reminder of the kinds of abiotic factors.) How many of the factors did you identify?
Try testing your friends or family. While on a walk or drive, see how many abiotic factors they can identify? You may have to help them be successful!