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BBiologyMathematicsS1 to S5Ecology
Ecology lab: counting plants with quadrats
Ecologists in parks like Akagera cannot count every plant. Sample a 50 m × 30 m grassland with quadrats, estimate how many plants there are, and see why random sampling matters.
LevelS1 to S5 (ecology), all levels for fieldwork
TimeAbout 40 min
You useQuadrats, means, estimates, diversity index
PriceFree: no account
🎯 Aim
To estimate the population size and frequency of plant species in a grassland using random quadrats, and to calculate Simpson’s index of diversity.
You will learn to
- Explain why sampling must be random.
- Estimate population size from quadrat counts.
- Calculate frequency and Simpson’s diversity index.
- Explain how the number of quadrats affects reliability.
🧭 What to do
- Look at the field: where are the daisies, thistles and acacia seedlings?
- Tap Random quadrat several times and read the counts.
- Choose a Species on the right and read your estimate of its population.
- Use × 10 several times and watch the estimate on the graph settle.
- Answer the questions using the class data (10 random quadrats).
- Write your conclusion and download your lab report.
📋 The data
Counts in 10 random 1 m × 1 m quadrats in a simulated 50 m × 30 m grassland.
🧠 Investigate: answer from the data
Type your answer and tap Check. Use 💡 Hint first; open the method only when you are stuck.
➕ Get more from this experiment
📝 Free
Print the worksheet (button above), download the data, and save your report. Teachers can project this page in class.
📦 Premium Lab Pack
1 000 RWF
- Fieldwork guide for real quadrats in the school compound
- Recording sheets and random number table
- Teacher guide and answer key
- Exam-style ecology questions with marking scheme
👩🏫 For teachers
Use it as a practical when apparatus is missing, as homework, or as a project. Free lesson plans help you plan, teach and assess.
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