The timberline is the edge of space, form closed herds in the trees. Must be distinguished from the tree line, no individual trees or groups of trees beyond which occur more. The distance between the two borders is often only small and is also influenced by man.
At the tree line, tree growth is greatly slowed. Because of the shortness of the growing season and because of this most strongly blowing wind leads to stunted tree shapes that grow only low and form dense thickets. This area is known as " coppice " or " belt " or " combat zone " or " fight forest ". The tree line, which is only kleinmaßstäblich -is a sharp line, shows a closer look - like many other boundaries in nature too - smooth transitions: trees grow towards the inhospitable climate less and less, until they finally fail. In different sections of the tree line tree species penetrate to the north most. This includes a group of perennial conifers, such as larch, pine, spruce and fir trees. Birch and alder trees often form a broad competition. Since many of these types take the form of bushes under load, one of the problems limiting the Arctic, to define a tree.
The crucial factor that the presence of trees is bounded to the north the climate - especially the temperature.
Forest boundary types
There are different types of forest boundaries:
The climatic treeline is a 10 - ° C isotherm of the warmest month, or the year mean air temperature of about 0 ° C is defined.
Species of the tree line
Some typical tree species of the tree line:
- Antarctic Beech bill ( Nothofagus antarctica)
- Arctic downy birch (Betula pubescens subsp. Tortuosa )
- Mountain Pine ( Pinus mugo ) or flop, flops pine, pine - Leg
- European larch (Larix decidua)
- Foxtail Pine ( Pinus balfouriana )
- Bristlecone Pine ( Pinus aristata )
- Ponderosa Pine ( Pinus peuce ) and Macedonian pine
- Rowan (Sorbus aucuparia )
- White Chunky Pine ( Pinus albicaulis )
- Swiss stone pine (Pinus cembra)
The alpine tree line in one place by local variables such as the slope, rain shadow, etc. dependent. Depending on these factors here there is a list of average height tree lines from various points in the world:
The highest peak of the Black Forest, the Bohemian Forest and the lumps protrude above the tree line, with only the chunk is above the natural tree line. The forest freedom of the summit of Feldberg and Big Arber is culturally determined. Although latter mountains are much higher than the chunks, they also lie south and not as exposed as the Brocken. Whether a tree line is, of course, can be the presence of a coppice seen, which is present in the chunk, but is missing from the Feldberg and the Great Arber. The 1214 meter high Fichtelbergbahn seems in this respect almost heranzureichen to the natural tree line, because the trees on the summit already show a certain tendency to cripple growth. The theoretical tree line would be at 1,300 meters, ie as high as in the near Giant Mountains. In the Erzgebirge there is elsewhere ( in statute) flops to almost 900 meters in height.
In the Alps, the frontier 1800-2200 meters above sea level is. By culture, such as Serviced by the tree line often appears lower in the Alps.