Mid- and late Holocene vegetation and environmental dynamics in the Llanganates National Park, Anteojos Valley, central Ecuadorian Andes

作者：Villota Andrea^*; Leon Yanez Susana; Behling Hermann

来源：Palynology, 2015, 39(3): 350-361.

DOI：10.1080/01916122.2014.977404

• palaeoecology
• mid-Holocene
• paramo
• vegetation dynamic
• central Ecuadorian Andes

The last ca. 4100 cal yr BP of palaeoenviromental conditions in the Llanganates National Park, central Ecuadorian Andes, has been reconstructed from the pollen record Anteojos Valley' (3984m elevation). The pollen record, dated with four radiocarbon dates, indicates that the local paramo vegetation was relatively stable with only minor fluctuations since the mid-Holocene. The paramo vegetation was characterised mainly by Asteraceae, Cyperaceae and Poaceae. The regional lower mountain rainforest vegetation is mainly represented by Moraceae/Urticaceae, and the upper mountain rainforest by Melastomataceae, Polylepis and Weinmannia. Between ca. 4100 to 2100 cal yr BP, paramo was the main vegetation type with a low presence of mountain rainforest, probably reflecting cool conditions. Between ca. 2100 cal yr BP and the present, the proportion of paramo vegetation increased with a decreased occurrence of mountain rainforest, suggesting cooler and moister conditions. Low frequencies of fires were evidenced since the mid-Holocene. However, there is a slight increase of regional fire between ca. 4100 and 3100 cal yr BP. The low abundance of larger carbonised particles since the beginning of the record suggests a low occurrence of local fire in the study area.

• 出版日期2015-9-2