After 8 years of annual pollen trapping across the tree line in western Norway: are the data still anomalous?

作者：Bjune Anne Elisabeth^*

来源：Vegetation History and Archaeobotany, 2014, 23(3): 299-308.

DOI：10.1007/s00334-013-0428-9

• Monitoring
• Pollen
• Pollen accumulation rates
• Pollen traps
• Concentrations
• Tree-line ecotone

The modern pollen production of local sub-alpine and alpine vegetation has been monitored over 8 years by using pollen traps situated along an elevational transect crossing the Pinus sylvestris and Betula pubescens elevational limits and continuing into the mid- and high-alpine vegetation in western Norway. The aim of the study is to monitor annual variation in the pollen production and hence the representation of common taxa found at or near the tree-line. The results can be used to derive critical pollen values that can be used to infer the presence of these taxa in the past, and to reconstruct past changes in tree line positions. Nine modified Tauber pollen traps were critically positioned in the vegetation from 663 to 1,347 m a.s.l. Three sub-aquatic traps were located in a small lake at 800 m a.s.l. just above the present-day B. pubescens tree-line. The traps have been sampled from 2004 to 2012. The results display large variations in pollen percentages and pollen accumulation rates from year to year, as well as great differences between the traps placed in the vegetation and in the lake, suggesting that further pollen trapping is needed to get a solid long-term average. The vegetation traps follow the vegetation distribution better and, as expected, give a more local signal than the lake traps.

• 出版日期2014-5