What’s going on in your garden? Study different areas of your backyard to see which is the most diverse.
Compare the biodiversity in a square of lawn, forest, and home garden. Which one has the largest variety of plants and animals?
- 4 1-foot long pieces of 1"x2" wood
- Four nails
- Safety goggles
- Margarine container or other small plastic container
- Plant identification book
- Insect identification book
- Notebook and pencil
Can you see biodiversity? In this experiment, you’ll make a square and see if you can determine what areas have the most plant and animal diversity.
1. First, get your nails, hammer, and wood. Find an adult to help you if you need it. Arrange the pieces of wood in a square with the edges overlapping. Place a nail in each corner to attach the wood together. This is your biodiversity square.
2. Now, choose three different sites: a garden, a forest (or other wild place) and a piece of lawn.
3. Create a hypothesis, your best guess about what is going to happen. Which environment will present the most biodiversity: the garden, the wild place, or the lawn? Why?
4. To keep things random, stand in the middle of each site and throw the clothespin into the air. Wherever it lands will be the middle of the place you will study.
5. Place your square in the first environment. Take a close look at the environment. What plants are living there? If you can’t identify them, look them up in your plant book. What animals are living there? Generally, these will be tiny animals such as insects. Look them up in your insect book. Can you see evidence of other animals, such as tracks, bite marks, or scat (animal poo)? Write all of your observations down in your notebook.
6. Do the same thing in each of the three environments. Which one has the highest number of different sorts of animals? Which one has the highest diversity of plants? Why?
Results: Depending on the particular square you choose, the forest or garden environment will have the most biodiversity.
What did you see in your square?
Lawn environments are mostly grass, although they may contain a weed or two. They are not very diverse environments.
Garden environments are as diverse as people make them, and part of what you’ll see will depend on where your clothespin landed. If it landed on a densely-planted area, you may have found the most diversity in this square, especially if that square included a plant that attracts many useful insects.
One of the challenges of this experiment is accurately gauging an area’s biodiversity. This can be hard, because it can be difficult to identify all of the different plants and animals that are in your square. It can also be hard because it’s difficult to decide how deep you should search! Biodiversity occurs at all levels, from huge trees to microscopic creatures in the soil. It’s likely that the forest or natural environment has the most biodiversity, but proving this would require a microscope. Forests and other natural environments have a large amount of microscopic fungi, invertebrates, and soil bacteria that help keep the underground ecosystem running.
To do this experiment well, you’d repeat it over and over until you got a lot of information from many different squares. This would allow you to more completely understand the diverse plants and animals in each area. Go back to each place you studied and do the experiment a few more times. How did this influence your results?