The diagram provides information about the water cycle in both forested and urban areas, giving an explanation of what happens when precipitation occurs both in forest and cities.
If we examine the left side of the diagram, we can see that evaporation and transpiration are higher in the forest than in the urban areas. That is because of the difference in the soil, the soil in the forest enhances the absorption of water, whilst the city soil does not permit too much infiltration and the transpiration and evaporation get reduced.
Another important feature is the difference between the baseflow on each area. While in the forested zones the baseflow has an important space which is bigger than in the cities until the permeable topsoil, the increased erosion of the soil in the urban areas reduces the baseflow of water and increases polluted runoff. This information is key to making better decisions about how to use the soil when we plan cities because it is very important to take care about the water cycle.