Pollen analysis of sediment core LV63-41-2

A total of 236 dry sediment samples with an average weight of 5-15 g were sampled every second cm from the studied core to investigate species distribution in the pollen assemblages. More than 300 pollen grains were calculated for species identification using a MICMED 6 microscope with amplification of 480x. Pollen grains were scarce in the core's lower part's sediment; however, the quantity required for statistical analysis was found in the core's upper part at 291 cm. Accordingly, species pollen compositions were determined for 81 samples, which is the required number of grains for statistical analysis. Sample preparation for spore-pollen analysis was carried out according to standard methods, with treatment with 10% KOH followed by separation with a heavy liquid. The pollen groups of trees and shrubs, herbaceous plants, and spores were calculated as proportions of the total number of detected pollen microfossils, and the percentages of taxa within the tree, shrub, and spore groups were determined.

本研究以目标岩芯为研究对象，以每间隔2 cm的间距采集了共计236份干燥沉积物样品，单份样品平均重量为5~15 g，旨在探究孢粉组合中的物种分布特征。每份样品统计超过300粒花粉粒以开展物种鉴定，观测使用放大倍数为480倍的MICMED 6型显微镜。该岩芯下部沉积物中的花粉粒含量极低，但在岩芯上部291 cm处的沉积物中，获取到了满足统计分析要求的花粉粒数量。据此，最终共确定了81份样品的物种花粉组成，这些样品的花粉粒数量均符合统计分析的标准要求。孢粉（spore-pollen）分析的样品制备遵循标准流程：先用10%氢氧化钾（KOH）溶液处理样品，随后通过重液进行分离。统计乔木、灌木、草本植物及孢子类群占所检测到的全部花粉微化石总数的比例，并分别确定乔木、灌木及孢子组内各分类单元的占比。