How do forests aid in water percolation?

Answer 1

Quite a few ways. Some include:

Roots break up the soil and improve it's characteristics for water uptake.

Organic matter in the soil from decaying wood and leaves improves the absorbancy of the soil.

The structure of a tree helps disperse and soften rainfall so that it does not concentrate into run off torrents as much which allows it to be absorbed more.

Cooler surface temperatures from the shade of the trees help reduce evaporation and allow the water to soak in more as well.

There are a lot more that have to do with soil structure, regulating erosion and other hydrology issues.

It is also important to realize that they do a great deal of filtering so that what does percolate is good quality input to the water table. This is definately a case where quality is far more important than quality, unless you are doing flooding and erosion studies.

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