4. The heath change the landform by adding to the depth of
soil and the nutrients found there. This occurs as the leaves of the heath drop
to the ground and decay. In addition, the roots help break rock and thicker
soil up. The result is that the soil soon becomes deep enough for the young
trees to live there.
The heath are unable to live there forever because when the
trees begin to get big, they change the habitat further. They do this by stealing
water and nutrients from the smaller heath, and more importantly, by shading
the heath so it doesn't receive enough sunlight.
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Long & Slichter