Biodiversity is the variety of all life on Earth – plants, animals, microorganisms and the ecosystems they form. It is the foundation of all living systems and provides us with countless natural resources. It also helps us adapt to changing environmental conditions.
Humans rely on biodiversity for food, timber and construction materials, medicines, and clean air and water. Biodiversity enables the nutrient cycling that supports ecosystem functions, such as decomposition and water retention. Plants, for example, give off oxygen, help keep soil fertile, and provide shade and shelter. They are the basis of many agricultural and forestry industries. Many medications, including the safe pain reliever aspirin, are derived from rainforest plants.
Ecosystems with a high level of biodiversity are more resilient against disease and natural disasters. For example, when the American chestnut tree blight killed all but one species of trees in an east-coast forest, the remaining trees survived because of the presence of other species. Biodiversity also provides a range of other valuable services.
For example, forests, peatlands, grasslands, wetlands and seabeds act as carbon sinks by storing atmospheric carbon dioxide. They also prevent erosion and flooding by absorbing rainfall. And, the fungi, earthworms and herbivores in a healthy forest ecosystem make nutrients available to plants by recycling them from dead matter – this is known as nutrient cycling.
Protecting biodiversity is a key element of addressing climate change. It is estimated that nature can deliver up to 30 percent of the emissions reductions needed by 2030. This can only be achieved if we preserve biodiversity and invest in nature’s services.