기능

• Acidic soil with excellent air permeability and water retention.
• The soil becomes yellow when it contains moisture and white when it dries, so it is easy to judge the dryness of the soil.
• It contains almost no bacteria, so it is also suitable for cuttings.
• Sixth grade: The construction and change of the land The soil is mainly used for gardening, but it is a kind of pumice which is a volcanic clast, so when it is washed out cleanly by the bowling method, feldspar, amphibole and olivine can be removed and observed.
• Even if volcanic ash is difficult to obtain, students can easily observe minerals.