Deserts and xeric shrublands

[1] Deserts and xeric (Ancient Greek ξηρός xērós 'dry') shrublands form the largest terrestrial biome, covering 19% of Earth's land surface area.

Climatic shifts such as global warming or the Milankovitch cycle (which drives glacials and interglacials) also affect the pattern of deserts on Earth.

Xeric shrublands can experience woody plant encroachment, which is the thickening of bushes and shrubs at the expense of grasses.

[5] This process is often caused by unsustainable land management practices, such as overgrazing and fire suppression, but can also be a consequence of climate change.

[7] The World Wide Fund for Nature highlights a number of desert ecoregions that have a high degree of biodiversity and endemism:[1]

Desertic region at the M'Sila Province , Algeria
Extent of deserts and xeric shrublands
The Nama Karoo in South Africa is a xeric shrubland that receives between 100 and 500 millimetres (4 and 20 in) of rain a year. [ 3 ]