Investigating the distribution of a plant
Setting the scene
In most habitats we find a number of different organisms. They are able to live together as long as they do not all have the same needs.
Aims
In this practical you will:
- record the numbers of a plant in a field
- consider how they live in their habitat with other organisms.
You will be working scientifically to:
- apply sampling techniques.
Safety
- Quadrats may be heavy and bulky.
- Inform your teacher if you have any allergies such as hayfever.
Equipment and materials
- quadrat
- 30-m transect line or string marked at 1-m intervals
- clipboard
Prediction
Predict where your named plant (e.g., dandelion) will be most abundant.
Method
1Lay out a 30-m tape in a straight line. Start in a shaded area and move out into the open. This is the transect line.
2Starting at 0 m on the transect line (in the shaded area), place a quadrat against the side of the tape.
3Count the number of named plants (e.g., dandelions) inside the quadrat.
4Record this figure in a suitable table.
5Repeat Steps 3 and 4 every five metres along the length of the transect.
Results
Design a suitable results table to record your results.
Questions
1Name the habitat you have studied.
2Name the plant you have counted.
3Describe the pattern or trend shown by your results.
4Suggest a reason for the change in distribution of the plant you have studied.
5Give the definition of the term niche and describe the niche of the plant you
studied.
6Describe how your named plants can survive in the same ecosystem as other plants.
7Suggest one advantage of using a transect line when sampling and explain why you placed the quadrat at fixed intervals along the transect line.
Extension
1Earthworms and snails are two types of herbivore that live in fields. Explain how
these two animals are able to co-exist in the field.
2Explain why different organisms are needed in an ecosystem, for example, in the African savannah, and how they can co-exist without conflict. Use an example to illustrate your answer.
3Annie carries out a similar experiment using a 0.25-m2 quadrat in her garden. Her garden is 10 m2. Use her results below to estimate the total number of daisies in
her garden. Show your working.
1 / 0 / 0
2 / 2 / 1
3 / 4 / 2
4 / 6 / 2
5 / 8 / 1
© Oxford University Press 2014
This resource sheet may have been changed from the original.