3.4 Soil Systems

3.1 Populations 3.2 Resources 3.3 Energy 3.4 Soil 3.5 Food 3.6 Water 3.7 Limits to Growth 3.8 Human Demand

Assessment Statements

3.4.1 Outline how soil systems integrate aspects of living systems
3.4.2 Compare & contrast the structure and properties of sand, clay and loam soils, including their effect on primary productivity.
3.4.3 Outline the processes and consequences of soil degradation.
3.4.4 Outline soil conservation measures.
3.4.5 Evaluate soil management strategies in a named commercial farming system and in a named subsistence farming system.

Key Vocabulary

Soil
- Sand
- Silt
- Clay
- Loam
Soil profile
- Horizons
- Organic material
- Bedrock
Erosion prevention
- Cover crops
- Terracing
- Contour plowing
- Wind breaks
Soil quality/degradation
- Leaching
- Salinization
- Irrigation
- Fertilizers
- Liming
- Crop rotation
- Fallowing

Essential Idea

Notes

Learning Activities

Soil Systems

Try these questions to practice communicating your thoughts and responding to IB prompts.

Determining Soil Texture

This site, by the Food and Agricultural Organization of the United Nations, walks through the process of determining a soil sample's texture. Use this to determine the texture of your sample.

Supplemental Readings

This video examines the structure and composition of soil as a resource. It is not important to understand the soil chemistry described in the video.

Supplemental Videos

This video tutorial outlines concepts related to the key vocabulary.

Video Tutorials

This video, produced by the National Soil Survey Center of the Natural Resources Conservation Service, introduces the differences in soil types and examines a variety of soil structures and their relationship to water movement through/within. It concludes with a brief discussion on how understanding these soil types are important for food production or other types of use.

This video outlines a simple test for determining soil

particle size and how to use this information, in

combination with the soil texture triangle, to determine

the soil type of the sample.

This video, produced by Economics of Land Degradation,

outlines the issues surrounding the value of soil as a

resource. It examines processes by which soil is

degraded and the impact this will have on society.

This video outlines many of the concerns related to soil

degradation (not just desertification) and the major

causes of these problems. It also suggests a variety of

potential solutions that are necessary in the face of

growing global populations.