Читать книгу The Terrestrial Macroinvertebrates of the Sub-Antarctic Iles Kerguelen and Ile de la Possession - Maurice Hulle - Страница 19

Grasslands (Figure 1.10) are present everywhere from the coast and up to 200 m a.s.l. These may be either almost monospecific grasslands with native plants such as Acaena magellanica, Leptinella plumosa or Azorella selago or introduced plants like grasses or dandelions. There are also mixed grasslands where native plants are in competition with one another or with introduced species. The monospecific meadows of Leptinella plumosa are coastal or supra-littoral, those of Acaena magellanica occupy the whole height and cover a large part of the slopes and those of Azorella selago are situated at higher altitudes and can develop up to 700 m a.s.l.

The meadows can be mixed with the rocky habitats. All the intermediaries between soil completely covered with vegetation and bare soil are possible. In the same way, grasslands may be very wet or very dry with plants in water deficit. Finally, coastal meadows can be heavily trampled by marine animals.

The invertebrate fauna of grasslands depend on plant composition, the proportion of area covered by vegetation or rocks and the water status of the soil. Introduced species such as the spider Tenuiphantes tenuis and the aphid Myzus ascalonicus may be plentiful. There is also the small native spider, Crozetulus minutus.