Extensive deforestation brings many problems to the environment and the people living there.
LOSS OF SOIL FERTILITY
Vegetation provides a protective cover over the soil. Through the nutrient cycle, vegetation helps to maintain the soil fertility. When raining occurs, nutrients enter the soil. Plant roots absorb the dissolved nutrients from the soil. When leaves fall, small organisms such as worms and insects break down the leaves as they decompose and these returns the nutrients to the soil. The fertility of the soil is maintained.
However, with the clearance of the forest, there is a loss of a protective cover for the soil. With deforestation, there will be a higher rate surface run off and these results in a higher rate of soil erosion and soil leaching. In soil erosion, the top soil is being removed or washed away by the higher surface run off. Soil leaching is a process by which nutrients are washed deeper into the soil and causes the top soil to become increasingly infertile over time. This, through soil erosion and soil leaching, the soil in the deforested area gradually loses its fertility.
; The nutrient cycle.
INCREASE IN WATER POLLUTION AND FLOODING
When the soil on cleared land begins to erode, more soil is washed into the rivers. The water quality is affected. Gradually the rivers sit up, increasing the likelihood of flooding in the low – lying areas downstream.
INCREASE IN GREENHOUSE EFFECT
As the tropical rainforest of the Amazon Basin covers a huge area, its large scale destruction is likely to have global impact. As more trees are felled, there will be fewer trees to remove the carbon dioxide from the atmosphere by the process of photosynthesis. The global carbon dioxide level is expected to increase in the greenhouse effect.
In addition, the burning of the forest contributes significant amounts of carbon dioxide, nitrous oxide and methane to the atmosphere, and worsening the greenhouse effect.
LOSS OF PLANT AND ANIMAL SPECIES
We have already seen how rich the tropical rainforest is in terms of the variety of plant life, especially when compared with the temperate forests. When trees are felled in the tropical rainforest, many valuable plant species are destroyed. An example of a valuable plant species in the Amazon rainforest which faces extinction is the Cinchona tree, from which quinine is extracted for the treatment of malaria.
Many animals die when he tropical rainforest is felled and burnt. Many others die because their natural habitat in the tropical rainforest has been destroyed. Over time, some animal species may become extinct.
DESTRUCTION OF HABITAT AND CULTURE OF THE AMAZONIAN INDIANS
The indigenous people of the Amazon Basin are the American Indians who are hunters and gatherers while others are shifting cultivators. They rely on the forest for their food, shelter and clothing. The extensive clearance of the tropical rainforest in the Amazon Basin has resulted in the destruction of their habitat and their traditional way of life or culture. When the tropical rainforest is cleared, they are forced to move out of the forest and many find it difficult to adapt to life outside the rainforest.