Urban Ecosystems

When people think of ecology, they usually imagine studies out in the country. The next thing they think of is studies involving the relationship of plants and animals to one another. They also imagine studies that show how organisms relate to the physical environment -- air, water, and soil. People and cities usually don't come to mind when ecology is mentioned.

Day 3: Percolation Protocol


Soil compaction affects the ground’s ability to absorb water Scientists compare data from different locations Data from different location must be gathered in the same way for it to be valid

Lesson Overview

Students will collect percolation data and determine the degree of soil compaction based on the time it takes for water to percolate into the soil.

1 class period
  • Number 10 coffee can with top and bottom removed
  • Permanent markers
  • Metric rulers
  • Watch with second hand or stop watches
  • Data collection sheet
  • Pencils
  • Class data collection sheet
  • Containers for carrying water
  • Containers marked at 50 mL
  • Science Journals
  • Scissors to clip grass



A how-to video on setting up a percolation experiment:



  1. Divide class into learning pairs. Give each pair a soup can with the top and bottom removed. Be sure sharp edges have been flattened with pliers. Ask students to make 4-6 marks with a permanent pen 2cm from the bottom of their can.
  2. Assign an area of the schoolyard to each pair. You may need to conduct this research on half of the schoolyard at a time depending on the size of the schoolyard and the location of the different areas. The goal is to get percolation data from each area.
  3. Ask students to choose their first percolation site within their area. Invite students to clear leaves and clip grass to the ground using scissors.
  4.  Invite students to twist the can into the ground 2cm (to the marks they made). Ask students to pour 50 ml of water into the can and time how long it takes for the water to soak into the soil.
  5. Ask students to write their time on the student data sheet.
  6. Gather as a class and compile data on the class percolation data sheet.
  7. The following questions may be included in the class discussion or students may respond in their science journals. What did you notice? Where do you think rainwater would go if it falls on an area with a high percolation rate vs. one with a low percolation rate?


NYS Standards
MST 1 - Mathematical analysis, scientific inquiry, and engineering design
MST 4- Physical setting, living environment and nature of science
Benchmarks for Science Literacy
1B Scientific Inquiry
2A Patterns and Relationships
4C Processes that shape the earth

Cary Institute of Ecosystem Studies | Millbrook, New York 12545 | Tel (845) 677-5343

Privacy Policy Copyright © 2015