Deforestation is the permanent removal of all the trees in an area. Throughout history forests have been cleared for agriculture, making new settlements and logging. Forests play a significant role in the earth’s environmental balance. Besides producing oxygen they store carbon dioxide so play a big role in controlling global warming. Forests found in the more temperate climates in the industrialised nations are very different to tropical rainforests. Forests found in temperate areas are likely to grow back(but are replaced by non-native trees like conifers) whereas tropical forests are not due to the balance between climate and vegetation being lost after they are removed. Tropical rainforests are home to 50% of the world’s plant and animal species. Recent rates of deforestation are thought to be having a significant effect on global diversity nutrient cycles and erosion.
Tropical rainforests are found in developing countries around the equator. The tropical rainforest is a major source of income for these countries, they can generate money by logging, mining, selling crops grown from deforested land and building dams. Thus governments encourage deforestation so they can relieve their debts and get sources for future growth. Lack of land and poverty is widespread in the developing world this added with population pressure forces people to clear forests and use them for firewood and use the land for growing crops on.
Deforestation is having a big effect on bio-diversity especially in the tropical rainforest because they are the most productive biomes on land and are home to around 50% of the world’s species with many unknown. Deforestation destroys habitats so drives some species to extinction. These species could have a lot of human value e.g. plants have provided anti-cancer drugs, hence we loose the possibility of finding cures for diseases like cancer which take millions of lives a year.
When forests are cut they are often burned this releases all the carbon dioxide the tree had stored in its lifetime into the atmosphere this contributes to rising green house gasses which cause global warming. Global warming will have several effects on global ecology including rising sea levels due to glaciers melting will cause coastal towns to be affected by frequent flooding and soil salination. Also rising sea temperatures could effect some organisms that live there. Rising temperatures could have a big effect on agriculture e.g. some plants will be possible to grow which before were not possible to grow.
Soil beneath tropical rainforest and conifers has only a thin layer of humus in contrast to deciduous forest, which has a thick layer of organic material. Most of the nutrients in the tropical rainforest are in the vegetation. So after deforestation the soil loses its fertility quickly after crops are grown on it continually which means poor people who can’t afford artificial fertiliser have to clear more land. Also without the canopy shielding the soil from intense rain and tree roots holding the soil particles together the little nutrients which are in the soil are leached out, leaving the soil as infertile. Even if artificial fertiliser is added and land is irrigated the nutrients will be leached out and end up causing freshwater pollution as well as soil salination.. Since theirs less vegetation cover more rain water gets into river and can lead to flooding further down the river.
Sustainable development is one way developing countries can make use of the forest resources without compromising those of future generations. Examples of sustainable development are rubber tapping and agroforestry. Trees are one of are most important renewable sources and should be looked after because they influence bio-diversity erosion and the climate. One way of reversing effects like global warming may be to plant more trees in areas where it is possible.