| Southern Andean steppe | |
| Map: | Ecoregion NT1008.png |
| Biogeographic Realm: | Neotropical |
| Biome: | Montane grasslands and shrublands |
| Border: | Patagonian steppe |
| Border1: | Valdivian temperate forests |
| Border2: | Chilean matorral |
| Border3: | High Monte |
| Border4: | Central Andean puna |
| Border5: | Central Andean dry puna |
| Country: | Chile |
| Country1: | Argentina |
| Area: | 178200 |
| Protected: | 21.165 |
| Protected Ref: | [1] |
The Southern Andean steppe is a montane grasslands and shrublands ecoregion occurring along the border of Chile and Argentina in the high elevations of the southern Andes mountain range.
This ecoregion is found from 3500mto5000mm (11,500feetto16,000feetm) in the north to 1800mto3000mm (5,900feetto10,000feetm) in the south. At higher elevations are found permanent snow, glaciers, and ice fields. At lower elevations, this ecoregion grades into Chilean matorral and Valdivian temperate forests to the west and High Monte to the east. To the north it transitions to the Central Andean dry puna and to the south the Patagonian steppe.
This ecoregion has a cold desert climate, Köppen climate classification BWk. Precipitation falls mainly in winter.
The flora of this ecoregion is adapted to its cold, dry, and windy climate. Many of the plant genera have evolved endemic species.
The plants on the western side of this ecoregion can be divided into three zones based on their growth forms and elevation. In the lower elevations, 2000mto2700mm (7,000feetto8,900feetm), grow large shrubs such as Chuquiraga oppositifolia and Nassauvia axillaris. In intermediate elevations, 2700mto3300mm (8,900feetto10,800feetm), grow small shrubs, tussock grasses, and cushions. These include Azorella madreporica, Laretia acaulis, and Stipa spp. In the highest elevations, extending to 3900m (12,800feet), grow small forbs, rosettes, and grasses such as Nassauvia lagascae, Oxalis erythrorhiza, Nassauvia pinnigera and Moschopsis leyboldii.
The plants on the eastern side do not grow in distinct zones. In the lower elevations, 1900mto2700mm (6,200feetto8,900feetm), grow plants of the genera Stipa, Adesmia, Mulinum, Nassauvia, and Chuquiraga. Higher, from 2700mto3300mm (8,900feetto10,800feetm), are shrubs and cushion plants of Oxalis, Junellia, Adesmia, Laretia and Azorella. At the highest elevations, 3300mto4500mm (10,800feetto14,800feetm), grow Senecio, Nassauvia, Chaetanthera, Draba, Barneoudia, Leucheria, and Moschopsis.
The fauna is similar to that of the Central Andean dry puna and the Patagonian steppe. Large mammals found here include the puma (Puma concolor), the Andean fox (Lycalopex culpaeus) and the vicuna (Vicugna vicugna) and guanaco (Lama guanicoe).
This ecoregion's high elevations and harsh climate make it unsuitable for development or farming, so it has experienced little habitat loss.
21.165% of the ecoregion is in protected areas.[1] Protected areas include: