Composting Competition
Who will win this heated race?Copyright 2013 Robert Bair, University of South Florida
In a multi-week experiment, students monitor the core temperatures of two compost piles, one control and one tended, to see how air and water affect microbial activity. They daily aerate and wet the "treated" pile and collect 4-6 weeks' worth of daily temperature readings. Once the experiment is concluded, students plot and analyze their data to compare the behavior of the two piles. They find that the treated pile becomes hotter, an indication that more microbes are active and releasing heat. Through this activity, students see that microbes play a role in composting and how composting can be used as a carbon management process.
Engineers use composting in many applications, such as large-scale municipal yard waste management, agricultural applications and at zoos to handle animal, yard and food waste. Composting is unique in that it is a natural process that can be applied in situations as simple as a backyard compost pile for household waste or as complex as an engineered solution to a city's waste problem.
After this activity, students should be able to:
- Present examples of microbes breaking down organic matter.
- Describe how heat is generated when microbes break down organic matter.
- Explain that to speed up the breakdown of organic materials microbes need air.
- Explain how composting fits in the carbon cycle.
- Identify instances when composting happens in nature.
- Describe how the process of composting biorecycles complex organic carbon matter into simpler carbon-based organic matter and nutrients.