🌍 Soil Composition & Horizons
Explore the structure and composition of soil, from the organic layer at the surface to the mineral-rich subsoil below. Learn what makes soil a living mixture and how decomposition creates fertile ground for plants. **What you'll learn:** - Soil is a mixture of mineral particles, organic matter, water, and air - The three main soil horizons and their characteristics - What organisms live in soil and how they break down organic matter - Why soil is important for plant growth and ecosystems
Questions in this quiz
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- Question 1
What are the FOUR main components that make up soil?
- Question 2
Which soil horizon is also called the organic layer?
- Question 3
The A-layer (topsoil) is where most plant roots grow and where soil organisms are most active.
- Question 4
What is the main difference between the A-layer and B-layer?
- Question 5
Which organisms help decompose dead organic matter in soil?
- Question 6
Decomposition is the process where dead organisms are broken down and turned into nutrients that plants can use.
- Question 7
In which soil horizon would you find mostly decomposed leaves and plant material?
- Question 8
Why is air important in soil composition?
- Question 9
The B-layer (subsoil) contains mostly mineral particles and very little organic matter.
- Question 10
Which of the following is NOT a component of soil?
- Question 11
How does decomposition contribute to making soil fertile?
- Question 12
Earthworms are an example of a decomposer that lives in soil.
- Question 13
Which soil horizon is found directly below the O-layer?
- Question 14
What colour is the O-layer typically?
- Question 15
Water is not an important component of soil because plants get water from rain.
- Question 16
Which of the three soil horizons is most important for plant growth?