Zur Langzeitökologie des Lärchen-Arvengürtels in den südlichen Walliser Alpen

Abstract.

Kaltenrieder P., Tinner W. and Ammann B. 2005. Long-term vegetation history at timberline in the Swiss Alps (Alpe d’Essertse, VS). Bot. Helv. 115: 137–154.

Palaeoecological studies in the “Alpe d’Essertse” area have provided much information about vegetation changes and timberline fluctuations during the Holocene. In this study we repeated previous biostratigraphic investigations using plant macrofossils to improve their temporal and taxonomic resolution and to test their reliability. By analyzing 0.5-cm layers of a lake sediment we reached a temporal resolution of 44 years, and we were able to reconstruct vegetation changes in the surrounding area at species level. The sedimentary record analyzed extends from the Late-Glacial to the late Holocene. Alpine grasslands (12’000–11’000 cal. BP) were afforested by Larix decidua, Juniperus nana, and Pinus cembra (11,000–9’600 cal. B.P.). Stable subalpine larch-stone pine-forests (9’600–4’900 cal. BP) were followed by shrublands and meadows as a consequence of the climatically and anthropogenically induced destruction of forest vegetation (4’900–2’600 cal. BP). Changes in the abundance of P. cembra and L. decidua needles as well as changes of the other taxa were consistent with those found in previous studies from the same lake. Our results demonstrate that plant-macrofossil records can be reproduced spatially and temporally on separate cores with independent ¹⁴C chronologies.