The study looked at different types of yellow soil in a karst area to understand how well they can hold water. They found that the soil's ability to retain water is affected by factors like density, organic matter, and soil depth. By using fractal dimensions based on soil particle size, they could estimate the soil's water retention capacity. The researchers discovered that the soil's ability to hold water can be predicted using these fractal dimensions, but the predictions were less accurate for deeper soil layers. Overall, the study showed that the soil's water retention capacity can be estimated using fractal dimensions, but the accuracy varies depending on the soil depth.