Cambridge O Level Biology · Syllabus 5090 · Relationships of Organisms with One Another and with the Environment
Deforestation
What is Deforestation?
The large-scale removal of trees from an area of forest, usually to clear land for agriculture or settlement or to extract timber, fuel or minerals. Its consequences follow from what the trees were doing: habitats and food sources are lost so populations decline and biodiversity falls; fewer roots bind the soil and less canopy intercepts rain, so topsoil is washed away and fertility falls; less water is intercepted and infiltrates so surface runoff increases and flood risk rises; and less photosynthesis together with burning or decomposition of the trees increases the concentration of carbon dioxide in the atmosphere.
This definition is part of the Relationships of Organisms with One Another and with the Environment chapter in Cambridge O Level Biology.
Questions students ask about Deforestation
Does replanting a forest undo deforestation?
Partly. Replanting restores tree cover, so soil is bound again, rain is intercepted, photosynthesis resumes and a future timber supply is secured. But a plantation of one fast-growing species provides far fewer habitats and food sources than a diverse natural forest, so much of the lost biodiversity does not return. Monitoring biodiversity, not just tree cover, is what settles whether the ecosystem has recovered.