Sampling Organisms

• What technique do scientists use to determine species abundance and distribution?

  Sampling
• What are abiotic factors?

  Non-living environmental factors
• Name three examples of abiotic factors.

  Light intensity, temperature, moisture
• How do abiotic factors affect organisms?

  They influence the number of different organisms
• What is random sampling used for?

  To compare numbers of organisms in areas
• What is a quadrat?

  A square frame for sampling organisms
• How do you use a quadrat in sampling?

  Place it on the ground and count organisms
• What hypothesis was investigated regarding ferns?

  Fewer ferns are found in light conditions
• How is random sampling conducted?

  By placing the quadrat at random locations
• Why is it important to place the quadrat multiple times?

  To ensure valid and representative results
• What is the equation for estimating total population size?

  Total population size = (total area / area sampled) * organisms counted
• What is a transect?

  A line used for sampling across a habitat
• How do you sample along a transect?

  Count organisms at intervals along the line
• Why is sampling along a transect useful?

  To see how species numbers change across habitats
• What happens to species on a sand dune as you move inland?

  Species change as you move inland
• What should you do to ensure valid results when sampling along a transect?

  Repeat the process multiple times
• What are the steps for using a quadrat in random sampling?

  1. Place the quadrat randomly on the ground.
  2. Count the number of organisms inside.
  3. Repeat at multiple random locations.
  4. Analyze the data for valid results.
• What are the steps for sampling along a transect?

  1. Place a tape measure across the habitat.
  2. Use a quadrat at set intervals along the transect.
  3. Count the organisms in each quadrat.
  4. Repeat the process for valid data.
• What are the differences between random sampling and sampling along a transect?

  • Random sampling:
  • Used to compare different areas
  • Quadrats placed randomly
  • Sampling along a transect:
  • Used to observe changes across a habitat
  • Quadrats placed at intervals along a line