Flora of Kerguelen

It is necessary to distinguish the terrestrial vegetation from the islands of that of water which surrounds them.

Terrestrial vegetation

The coastal grounds, until worms 50m of altitude, are generally covered with a herbaceous low vegetation, classified in the category of the Toundra high S. Plus, the mineral ground dominates and the vegetation is done rarer, by scattered tufts, or more discrete, in the form of foam S and of Lichen s.
No tree, no shrub marks the landscape. It was not always thus because in certain sediments, one can find trunks fossilized of trees of the family of the Araucariaceae, witnesses of times geological where Kerguelen knew a Climat hotter than aujourd'hui.
Originally, the principal type of basic vegetation altitude consisted of a carpet thick and continuous of azorelle ( Azorella selago ) on which could be established various other species like celebrates it Chou of Kerguelen, Pringlea antiscorbutica (family of the Brassicaceae). The azorelle one (family of the Apiaceae) has a growth in cushion indeed: the growth of the year forms a tight layer which comes to surmount that of the previous year. The species Lyallia kerguelensis (family of the Hectorellaceae), the only strictly endemic species of the archipelago, also has a growth in cushion. The cushions of azorelle can exceed 1m nearby thickness and feet to incorporate itself in a continuous tablecloth. Besides it is very difficult to go in this type of vegetation, it is necessary to abstain from some not to damage it. On the other hand, this tender medium is ideal for certain species of marine birds which can dig their burrows of reproduction.
there The introduction and the proliferation of the rabbits caused the destruction of this habitat for which replaced a monospecific meadow Acaena adscendens (family of the Rosaceae), plant resembling small a Pimprenelle. It is only on the islands and unscathed small islands of rabbits that one can find the carpets of azorelle today. The cabbage of Kerguelen practically underwent same the sort.
The establishment of the other mammals also has consequences on the vegetation: consumption of cabbage seeds of Kerguelen by the Mouse thus reducing the capacities of regeneration of the species, consumption of the Lichen S by the Reindeer S, etc.
In the flat funds or close to the brooks, the grounds are often gorged with water. It develops a boggy vegetation then to with it dominated by foams. This vegetation can appear homogeneous surfaces some but cover sometimes with the moving grounds, the " souilles" , in which the hikers are inserted brutally until the ceinture.

Marine vegetation

As much the terrestrial vegetation is developed little, as much the marine flora is exuberant, in particular thanks to the presence of giant brown algas: the Macrocystis ( Macrocystis will pyrifera ) which form true underwater forests and the Durvilléa S ( Durvillaea antartica ) which scallops the major part of the rock coasts.

The “herbaria” of Macrocystis develop in water of which the depth generally lies between 3 and 20 Mr. Accrochées at the bottom by ramified cramps, the algae are drawn up upwards in the form of braided columns several tens of cords then are spread out lengthily surfaces some thanks to floats placed at the base of multiple slings similar to corrugated sheets. The Macrocystides can cover very great extents (that which surrounds the islands Leygues is vaster than the Forêt of Fontainebleau) where navigation is practically impossible because the thin straps are gotten mixed up in the propellers and block them. The forests of Macrocystis lodge in the Kerguelen islands relatively little vertebrate but much invertebrates coloured as well as a great diversity of red algas. The storms regularly tear off significant amounts of giant algae which come to be failed and rot on the beaches in the form of mattress which can reach several meters thickness. These strandings of algae form one of the essential bases of the local ecosystem.

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