5.1.20 (HL)—Soil property analysis

Match each test to the property it measures: texture, organic matter, water, infiltration, bulk density, colour or pH answers different questions.

Use sand, silt and clay percentages that total 100% to locate a point on the soil texture triangle. Other tests answer different questions: loss on heating estimates organic matter, mass change estimates water content, infiltration measures entry rate, bulk density indicates compaction, colour is descriptive and pH measures acidity.

Local practice data give Soil B as 20% clay, 40% silt and 40% sand. Plotting those three percentages on the texture triangle classifies it as loam; that label does not by itself determine organic matter, pH or compaction.

Choose the test from the question: infiltration helps assess water entry, bulk density compaction, pH acidity, and the texture triangle mineral particle proportions.

A measured proxy is not the whole process; name the limitation and context.