Soil indicator relationships allow you to determine key drivers of soil functioning. The diagram below shows how clay content is an over-riding determinant of biological processes within the soil.
Ultimately, clay content, along with rainfall, determines the capacity of the soil to build and store carbon, to break down organic matter and to provide an organic source of nutrients for plants and animals.
A scatter diagram visually displays the relationship between the two chosen soil quality indicators.
A positive upward relationship occurs when data points with higher values on the horizontal (x-axis) correspond to higher values on the vertical (y-axis).
A negative downward relationship occurs when data points with higher values on the horizontal (x-axis) correspond to lower values on the vertical (y-axis).
If the data points are scattered with no obvious trend then there is no simple relationship between the two soil quality indicators.