In what ways do deforestation activities affect flood risks?

Deforestation activities increase flood risks by reducing the amount of water absorbed and stored by trees and soil.

Deforestation, the process of clearing large areas of trees, has a significant impact on the environment, particularly on the risk of flooding. Trees play a crucial role in the water cycle, absorbing rainfall and releasing it slowly into the atmosphere through transpiration. This process helps to regulate the amount of water in the soil and reduces the risk of flooding. When trees are removed, the soil loses its ability to absorb and store water, leading to an increase in surface runoff.

Surface runoff is the water flow that occurs when the soil is saturated and excess water from rain, meltwater, or other sources flows over the Earth's surface. This is a major contributing factor to flooding, particularly in areas where deforestation has occurred. Without trees to slow down the runoff, water can quickly accumulate in rivers and streams, causing them to overflow their banks.

Furthermore, trees and their root systems help to bind and stabilise the soil. When trees are cut down, the soil can become loose and more susceptible to erosion. This can lead to an increase in sediment in rivers and streams, which can block waterways and increase the risk of flooding.

In addition, deforestation can alter the local climate, leading to changes in rainfall patterns. Trees release water vapour into the atmosphere through transpiration, which contributes to cloud formation and rainfall. When large areas of trees are removed, this can disrupt the local climate and potentially lead to more intense and frequent rainfall events, further increasing the risk of flooding.

In conclusion, deforestation activities can significantly increase the risk of flooding by reducing the amount of water absorbed and stored by trees and soil, increasing surface runoff, causing soil erosion, and altering local rainfall patterns. It is therefore crucial to manage and reduce deforestation to mitigate these risks.