Final answer:
The primary impact of lacking makatea rock in a deforested area is severe soil erosion due to the absence of tree roots to stabilize soil and leaves to protect it from rain impact. This can lead to nutrient loss and makes it difficult for forests to regrow, which in turn affects climate and the water cycle.
Step-by-step explanation:
The primary impact on the degree of deforestation in an area without makatea rock is closely related to soil erosion. In regions where Makatea rock is absent, and tropical deforestation occurs, soil erosion becomes a more severe problem. Trees are integral to maintaining soil stability; their roots hold the soil together, and their canopy reduces the impact of rainfall.
With deforestation, the loss of these trees means the soil is more susceptible to being washed away during heavy rains. This degradation results in the loss of critical nutrients, which are often in decaying material at the base of the trees, therefore affecting the land's ability to support new forest growth or agricultural productivity. The impact extends beyond soil erosion, as deforestation can also lead to changes in local climate, such as increases in temperature and alterations in rainfall patterns, which further exacerbate the ability for forests to regrow and affect the overall ecosystem.
Deforestation's contribution to climate change and its interference with the water cycle are also prominent issues that arise when forests are cleared, which are explicitly linked to soil erosion and agricultural challenges.