The Sub-Alpine belt is biome : a geographical and mountain belt located below the boundary of woody vegetation and above the forest mountain belt .
The temperature in the subalpine zone rises in the summer to a maximum of +24 ° C on hot sunny days, and usually does not reach +16 ° C. Frost possible at any time of year. Although winter temperatures can be higher than those occurring at lower altitudes, as a rule, higher than minus 23 ° C, the ground at this time is covered with thick snow cover, which lasts for 6-8 months during the year, and some drifts melting only in summer. Convective precipitation, mainly thunderstorm , often falls as snow pellets or hail .
The belt height is different at different latitudes. For example, in the Caucasus and the Alps, the subalpine zone is located at an altitude of 1,700–2300 m above sea level, on the southern slopes of the Himalayas at an altitude of 3,200–4,000 m, and at higher latitudes its level drops sharply (for example, in the Kuril Islands it drops to seas).
Content
Flora and fauna
Communities formed by subalpine vegetation in different regions of the globe can be grouped into 4 groups:
- high grass subalpine meadows [1] ;
- communities of low shrubs and shrubs , including elfin forms;
- grassy wastelands and wasteland meadows consisting of short growing grass ;
- Clarified forests of park type - subalpine light forests and crimped forests .
Mountains of North America
In the Rocky Mountains, flora is characterized by the predominance of subalpine fir ( Abies lasiocarpa ) and Engelmann fir ( Picea engelmannii ). There are no trees growing down the slope, such as yellow pine ( Pinus ponderosa ) and pine coniferous pine ( Pinus contorta ). White pine ( Pinus albicaulis ) and spinous pine ( Pinus Longaeva ), Douglas ( Pseudotsuga menziesii ), European fir ( Abies concolor ) and various species of juniper ( Juniperus ) can be found in some places.
Due to severe winters and lack of food sources, the amount of local fauna is very limited. Sometimes bears and cougars rise to these heights. Among the mammals living here are the lynx , the American white hare ( Lepus americanus ), the American marten ( Martes americana ) and various types of squirrels ; of the birds are the mountain Gadget ( Poecile gambeli ) and the blue jay ( Cyanocitta stelleri ), as well as owls , nuthatches and finches .
See also
- Alpine belt
- Mountain forest belt
Notes
Literature
- Subalpine belt / Yu. K. Efremov // Strunino - Tikhoretsk. - M .: Soviet Encyclopedia, 1976. - ( Great Soviet Encyclopedia : [in 30 t.] / Ch. Ed. AM Prokhorov ; 1969-1978, v. 25).
- Benedict, Audrey D. (1991). Sierra Club Naturalist's Guide: The Southern Rockies (1st ed.). San Francisco: Sierra Club Books. ISBN 0-87156-647-8 .