Loss of biodiversity

Loss of biodiversity or biodiversity loss is the ongoing extinction of species worldwide, and also the local reduction or loss of species in a certain habitat or ecological niche or biome.

The latter phenomenon can be temporary or permanent, depending on whether the environmental degradation that leads to the loss is reversible through ecological restoration / ecological resilience or effectively permanent (e.g. through land loss). Global extinction has so far been proven to be irreversible.

Even though permanent global species loss is a more dramatic phenomenon than regional changes in species composition, even minor changes from a healthy stable state can have dramatic influence on the food web and the food chain insofar as reductions in only one species can adversely affect the entire chain (coextinction), leading to an overall reduction in biodiversity, possible alternative stable states of an ecosystem notwithstanding. Ecological effects of biodiversity are usually counteracted by its loss. Reduced biodiversity in particular leads to reduced ecosystem services and eventually poses an immediate danger for food security, also for humankind.

The current rate of global diversity loss is estimated to be a 1000 times higher than the (naturally occurring) background extinction rate and expected to still grow in the upcoming years.

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