Pollen counts for the Holocene sediment sequence retrieved from Lake Loitsana, Finland

This dataset provides counts the pollen counts for the Holocene sediment sequence retrieved from Lake Loitsana (Finland) in 2008. Counts per taxon are presented against both depth (m) and age (cal ka. BP); sample volume, the number of Lycopodium tablets added during sample preparation, the number of Lycopodium spores per tablet, and the number of Lycopodium spores encountered during analysis are also presented. Two age/depths models are presented: the first model represents the original age/depth model applied to the records (Shala et al., 2014; 2017) and the second age/depth model, which is the author-preferred version, presents updated age-estimates derived using the r package 'Bacon' (Blaauw and Christensen, 2011). The pollen dataset provides information on terrestrial and aquatic vegetation dynamics (Salonen et al., 2013). A total of 55 samples was analysed, with samples prepared using standard KOH, HF and acetolysis treatments and counted using a light microscope (400× magnification). Non-pollen palynomorphs and conifer stomata were also counted from the pollen slides.

本数据集统计了2008年从芬兰洛伊察纳湖（Lake Loitsana）钻取的全新世沉积序列中的花粉含量。各分类群的花粉计数结果同时对应沉积物深度（单位：米）与年龄（cal ka. BP，即校准千年BP）；此外还提供了样品体积、样品制备过程中添加的石松（Lycopodium）标片数量、每片石松标片所含孢子数，以及分析阶段计数得到的石松孢子数。本次数据集包含两套年龄-深度模型：第一套为应用于该沉积记录的原始年龄-深度模型（Shala等，2014；2017）；第二套为作者推荐的最优版本，其更新后的年龄估算值通过R语言包"Bacon"（Blaauw与Christensen，2011）计算得出。本花粉数据集可用于反演陆地与水生植被的动态变化过程（Salonen等，2013）。本次研究共分析55个沉积物样品，样品制备采用标准的氢氧化钾、氢氟酸与乙酰解处理流程，花粉计数通过光学显微镜（400倍放大）完成。此外，研究人员还对花粉玻片上的非花粉类孢粉有机物（non-pollen palynomorphs）与针叶植物气孔进行了计数。