Indiscriminate felling of trees has led to destruction of forest cover. Trees are natural consumers of carbon dioxide one of the greenhouse gases whose built-up in the atmosphere contributes to global warming. Destruction of trees pumps into the atmosphere even more carbon dioxide, along with methane, another major greenhouse gas. Once forests have been cut down, essential nutrients are washed out of the soil all-together. This leads to "Soil erosion" which makes the land unusable and can, in turn, lead to disastrous flooding since there is no soil to soak up the rain.