Sierra de la Laguna pine-oak forests

The Sierra de la Laguna pine-oak forests is a subtropical coniferous forest ecoregion, found in the Sierra de la Laguna mountain range at the southern tip of the Baja California Peninsula, Mexico.

It is found within Los Cabos Municipality and eastern La Paz Municipality of southern Baja California Sur state.

Setting

The ecoregion encompasses an area of 1,100 km² (420 sq mi). The pine-oak forests are found above 800 metres (2,600 ft) in elevation, and are surrounded at lower elevations by the Sierra de la Laguna dry forests. The pine-oak forests have a unique and diverse flora and fauna, including 694 plant species, of which approximately 85 are endemic.

The higher elevation gives the ecoregion a subtropical to temperate climate, in contrast to the dry tropical climate of the lowlands. Rainfall is higher than the lower-elevation dry forests and deserts of the peninsula, averaging 760 mm annually. Rain falls mostly in the summer, with occasional winter rains.

Flora

The composition of the pine-oak forests varies with elevation; oak woodlands predominate from 800–1,200 metres (2,600–3,900 ft) in elevation, with oak-pine woodlands between 1,200–1,600 metres (3,900–5,200 ft) in elevation, transitioning to pine-oak forests above 1,600 metres (5,200 ft) in elevation. Mosses and lichens are abundant throughout.

The oak woodlands from 800–1,200 metres (2,600–3,900 ft) in elevation are warmer and drier, with evergreen oaks predominant (principally Quercus devia; Quercus arizonica and Quercus rugosa have a limited distribution), along with lower trees and shrubs such as Dodonaea viscosa, Sideroxylon peninsulare, and Buddleia crotonoides.

Above 1,200 metres (3,900 ft) in elevation, the oak woodlands transition to oak-pine forests. The only pine present is an endemic subspecies of Mexican Pinyon, Pinus cembroides subsp. lagunae, mixed with oaks, including Quercus devia and Quercus tuberculata, and other broadleaf trees, including Arbutus peninsularis and Nolina beldingi. Lower trees and understory shrubs include Calliandra peninsularis, Mimosa xanti, Heterotoma aurita, Verbesina pustulata and Hypericum peninsulare. Above 1,600 metres (5,200 ft) in elevation, pine predominates, mixed with oaks, and with an understory of grasses (Muhlenbergia spp. and Festuca spp.).

See also

• Natural history of Baja California Sur
• Conifers of Mexico

External links

• "Sierra de la Laguna pine-oak forests". Terrestrial Ecoregions. World Wildlife Fund.