~~~- 199 I
Berlin-Stutt gart,
D~cember 15, 1993 J
ökologische Bedingungen hochandiner Moore Chiles zwischen 18°00' (Arica) und 40°30' (Osorno) südl.. Br.
Flora
von Barbara RuTHSATZ , Trier mit 8 Photos, 10 Figuren und 2 Tabellen
Flora and ecological conditions of high andean mires of Chile between 18 °00' (Arica) and 40° 30' (Osorno) s.lat. Abstract. The flora of 152 mire sites from the high Andes of Chile between Arica (Parinacota: 18°10' s.lat.) and Osorno (Antillanca: 40°45' s.lat.) has been presented in a comparing table. Water and soil samples were collected from a representativ e number of mires and chemically analyzed, especially with respect to the base supply of the mire sites. The typical growth form of the high andean mires have the cushion forming Juncaceae: Distichia muscoides, D. filamentosa, Oxychloe andina, Patosia clandestina and the Cyperaceae: Trichophorum atacamensis. They are accompanie d by other Cyperaceae, Juncaceae as well as Gramineae, Asteraceae, a. o., altogether about 230 species. Because of the floristic differences one can distinguish the cushion plant mires of North Chile (18° to about 25° s.lat.) from those of central Chile (about 27° to 38° s.lat.) and make moreover subdivisions. A group of plant species which is growing in the Andes mostly from Colombia to Patagonia is common to north and central Chile (i. e. Werneria pygmaea). The mires of N-Chile are dominated by species from the wet tropical Andes (i. e. Distichia). The mire sites visited south of the Paso del Pino Hachado (38°38' s.lat.) do contain already the cushion plant Oreobolus obtusangulus (Cyperaceae), typical for the magellanic bogs. Many species with predominant ly southern distribution patterns have been found already at the Paso Pehuenche (36 ° s. lat.) or somewhat farther north accompanyin g the cushion plants coming from the north. All the mires treated show minerotroph ic characters. The north to south gradient of the mire Hora is decisively influenced by the aridity /humidity of the climate and the distribution of the precipitation throughout the year. Also the base supply and saltstress is ruled by the same factor. The grazing intensity changes the dominance relation between the mire plants. Overgazing is favoring the cushion and toxic plants and damages especially the grasses and sedges.
1.
Einleitun g
In den Quellgebie ten und entlang der Oberläufe vieler Andengewässer haben polsterförmig wachsende Juncaceen und Cyperacee n zusammen mit anderen Pflanzen Moore gebildet, die die entscheide nde Lebensgru ndlage für die heimischen Kameliden Guanaco und Vicufia, viele Vögel, einige Nagetiere und andere Tiergrupp en sind. Seit langem werden sie auch vom Menschen und seinen Weidetieren intensiv genutzt. 0340-269X/93/0023-0157 $ 10.75 Gehrüder tlolmtJrael~er, D-14129 Berlin · D-70176 Stuttgart