The study looked at how different types of plants affect the amount of water in the soil in a specific area. They found that certain plants like oak trees and birch trees can hold more water in the soil compared to grasslands or abandoned land. This is because these plants help improve the soil quality by adding organic matter and increasing soil porosity. The researchers used a mathematical model to show the relationship between soil moisture and soil potential. Overall, the type of vegetation in an area can greatly impact how much water is stored in the soil.