Investigating Living Soil Components

Earth ecoSTEM Kit Materials Used: Trowels

ENGAGE - Students Observe This Phenomenon

GATHER

GATHER Energy Investigations

REASON

REASON Investigating Soil Components

EXPLORE a Kit-Supported Learning Experience

Working in teams of four, students will use their trowels to dig 4” deep samples from various locations and spread the soil out on white paper or cloth to identify components. (Do not use potting soil, which has no living organisms). Lenses and jars will help students see insects. Bacteria can be seen microscopically. Return soil to holes afterwards; wash hands!

EVALUATE

Given a variety of ingredients, students should be able to design and make an edible soil model and explain that soil is composed of mineral content (broken bits of rocks or ‘parent material’), organic content (living organisms and dead / decomposing matter), water and air. Decomposing things include rotting leaves. Living organisms include various animals and the “FBI”: Fungi (underground part called mycorrhizae), Bacteria, and Insects in various stages (macroinvertebrates).

ELABORATE

Fungi, Bacteria, Invertebrates:

Students can find a plant with mycorrhizae, dig it up, cut the roots, and grow a “trap culture”  of the soil fungi for 4 months and then “inoculate” other plants to extend their root systems.  They can observe these microscopic images of soil bacteria. They can observe insects and other soil macroinvertebrates.

 

EXTEND

Students can build a Berlese Funnel to make soil macroin-vertebrates emerge from a soil sample. Follow the direction or make this into an engineering design challenge.

This video explains the Soil Food Web, as depicted in  this poster. Students can visit The Microbe Zoo to learn more about soil and compost critters.

COMMUNICATE

Revised EXPLANATION

After making sense of a core idea by engaging in science or engineering practices through the lens of crosscutting concepts, students revise their original explanations of a phenomenon.

EMPOWERMENT

Students may propose solutions to mineral soils and carry out a project such as adding mulch to increase soil organisms.