Why is the study of iron or manganese nodules important in soil science?

The study of iron or manganese nodules is significant in soil science because they can indicate the presence of seasonal water tables. These nodules often form in conditions where there is periodic saturation of the soil, which leads to processes such as reducing environments where iron and manganese are leached out and then precipitated as nodules when conditions change. Their presence suggests moisture dynamics and water table variations over time, which can greatly influence soil properties and the types of vegetation that can thrive in that soil. Understanding these nodules provides insights into how soil behaves in response to water availability, making them a valuable indicator for assessing soil health and hydrology.