A serious effect is the loss of species. Eighty percent of species live in the tropical rainforests, and multiple species have and will lose their habitats due to deforestation. Without their habitats, they become more accessible to hunters and poachers. Many species are unique to the forests and become extinct because deforestation.
Deforestation also affects people. Millions of people rely on forests for hunting, gathering, and to get products such as rubber. Their livelihoods are disrupted without the trees;causing social conflict and migration.
The clearing of the forests also helps speed up global warming. Carbon dioxide and other greenhouse gas emissions, which contributes to rising temperatures and changes in the weather, are lessened by forests. Deforestation actually is responsible for about 15% of greenhouse gas emissions.
Soil erosion increases too. Soil need trees to anchor it, or it can be sweep the land into rivers. Many agricultural plants can't grasp the soil and the fertile earth washes away. Scientists estimate that a third of the world's arable land has been lost thought soil erosion and other types of degradation since 1960.