An ecoregion (ecological region) or ecozone (ecological zone) is an ecologically and geographically defined area that is smaller than a bioregion, which in turn is smaller than a biogeographic realm.Ecoregions cover relatively large areas of land or water, and contain characteristic, geographically distinct assemblages of natural communities and species.

Setting. The Sahara Desert is the world's largest hot, non-polar desert and is located in North Africa.It stretches from the Red Sea to the Atlantic Ocean.The vast desert encompasses several ecologically distinct regions. The Sahara Desert ecoregion covers an area of 4,619,260 km 2 (1,783,510 sq mi) in the hot, hyper-arid center of the Sahara, surrounded on the north, south, …

The Northern Basin and Range ecoregion is a Level III ecoregion designated by the United States Environmental Protection Agency (EPA) in the U.S. states of Oregon, Idaho, Nevada, Utah, and California.It contains dissected lava plains, rolling hills, alluvial fans, valleys, and scattered mountain ranges in the northern part of the Great Basin.Although arid, the ecoregion is higher …

Lasostep – formacja roślinna stanowiąca w Eurazji strefę przejściową między stepami na południu a lasami liściastymi na północy. Ma charakter makromozaiki tworzonej przez przemieszane wzajemnie płaty zbiorowisk stepowych i leśnych. W części północnej lasostepu przeważają powierzchniowo lasy, a w południowej – stepy.