Sedimentary charcoal data set from the Villena Paleolake (VL3 core)

1. Data set, and sampling methods This data set contains the quantification of sedimentary charcoal from the VL3 record of the Villena Paleolake (Villena, Alicante, Spain). The analyzed section covers the Early and Middle Holocene section of this deposit according (Jones et al., 2018), depths between -120 a -400 cm, with centimetric sampling interval which has produced a total number of 281 samples. 2. Treatment The samples have been treated as follows, adapting the methods published by Rhodes (1998) and Talon et al.(1998): Samples were soaked in 10% H2O2 for 12h for sediment deflocculation and to bleach non-charcoal organic material. After this first step, it was noted if the samples contained shell fragments. A 10% HCl solution was used in samples with high carbonate content. Then samples were sieved (150µ) under a soft-water jet. The samples were stored in distilled water for later counting. 3. Quantification procedures Each sample was washed with distilled water, employing a 150 micron sieve. The wet sample was examined under binocular microscope Stereomicroscopy CETI STEDDY-T at 40 magnification, using a reference grid with squares of different size categories (cat. 0,5; cat. 1, cat. 2, cat. 3, cat. 4 and cat. 5). The total number of examined charcoal was also calculated. Each size category corresponds to one of the following area categories Cat. 0,5: 0,015625mm2; Cat. 1: 0,0625 mm2 (0,25 mm*0,25 mm); Cat. 2: 0,0125 mm2; Cat. 3: 0,25 mm2; Cat. 4: 0,5625 mm2; Cat. 5: 1 mm2. In the Excel spreadsheet, the area is multiplied by the number of fragments of each category. The sum of the areas is also calculated. In addition, oocytes and insects were also counted. References Carcaillet, C., Bouvier, M., Fréchette, B., Larouche, A. C., Richard, P. J. H. (2001). Comparison of pollen-slide and sieving methods in lacustrine charcoal analyses for local and regional fire history. The Holocene 11 (4): 467- 476. Clark, J. S. (1988). Particle motion and the theory of charcoal analysis: Source area, transport, deposition, and sampling. Quaternary Research 30 (1), 67-80. Jones S.E., Burjachs, F. Ferrer-García C., Giralt, S., Schulte, L., Fernández-López de Pablo, J. (2018). A multi-proxy approach to understanding complex responses of salt-lake catchments to climate variability and human pressure: A Late Quaternary case study from south-eastern, Spain. Quaternary Science Reviews https://doi.org/10.1016/j.quascirev.2017.12.015. Ohlson, M. and Tryterud, E. 2000. Interpretation of the charcoal record in forest soils: forest fires and their production and deposition of macroscopic charcoal. The Holocene, 10(4), 529-525. Rhodes, A. N. (1998). A method for the preparation and quantification of microscopic charcoal from terrestrial and lacustrine sediment cores. The Holocene 8 (1), 113-117. Talon, B., Carcaillet, C., Thinon, M. (1998). Etudes pedoanthracologiques des variations de la limite superieure des arbres au cours de l'Holocene dans les Alpes françaises. Geographie physique et Quaternaire 52 (2), 195-208.1. 数据集与采样方法 本数据集涵盖西班牙阿利坎特省比列纳古湖（Villena Paleolake）VL3岩芯记录的沉积炭屑定量数据。根据Jones等人（2018）的研究，本次分析的层段覆盖该沉积物的全新世早中期，采样深度区间为-120 cm至-400 cm，采用厘米级采样间隔，总计获得281个样品。 2. 样品前处理 本研究参考Rhodes（1998）与Talon等人（1998）发表的方法，对样品进行如下处理：将样品置于10%过氧化氢（H₂O₂）溶液中浸泡12小时，以实现沉积物解絮凝并漂白非炭屑类有机物质。第一步处理完成后，记录样品中是否含有贝壳碎屑；针对碳酸盐含量较高的样品，使用10%盐酸（HCl）溶液进行脱碳酸盐处理。随后采用软水流过150微米（150µ）筛网对样品进行筛分，最后将样品保存在蒸馏水中以待后续计数。 3. 定量分析流程 每份样品均使用150微米筛网以蒸馏水冲洗。将湿润样品置于CETI STEDDY-T型双目体视显微镜下，以40倍放大倍率进行观察，并使用带有不同尺寸方格的参考网格进行分类统计（类别0.5、类别1、类别2、类别3、类别4、类别5），同时统计所观察到的炭屑总数量。 各尺寸类别对应如下面积参数：类别0.5：0.015625 mm²；类别1：0.0625 mm²（0.25 mm×0.25 mm）；类别2：0.0125 mm²；类别3：0.25 mm²；类别4：0.5625 mm²；类别5：1 mm²。 在Excel电子表格中，将各分类的炭屑碎片数量乘以对应面积，最终计算得到总炭屑面积。此外，本流程同时对卵母细胞与昆虫残体进行计数。 参考文献 Carcaillet, C., Bouvier, M., Fréchette, B., Larouche, A. C., Richard, P. J. H. (2001). 湖泊炭屑分析中花粉玻片法与筛分法的对比：用于局地与区域火历史研究. 《全新世》(The Holocene) 11(4): 467-476. Clark, J. S. (1988). 颗粒运动与炭屑分析理论：源区、搬运、沉积与采样. 《第四纪研究》(Quaternary Research) 30(1): 67-80. Jones, S. E., Burjachs, F., Ferrer-García, C., Giralt, S., Schulte, L., Fernández-López de Pablo, J. (2018). 多代用指标方法解析盐湖流域对气候波动与人类活动压力的复杂响应：以西班牙东南部晚第四纪研究为例. 《第四纪科学评论》(Quaternary Science Reviews) https://doi.org/10.1016/j.quascirev.2017.12.015. Ohlson, M., Tryterud, E. (2000). 森林土壤炭屑记录解读：森林火灾及其产生与沉积的宏观炭屑. 《全新世》(The Holocene) 10(4): 529-535（注：原文标注页码为529-525，疑似笔误）. Rhodes, A. N. (1998). 陆地与湖泊沉积岩芯中显微炭屑的制备与定量分析方法. 《全新世》(The Holocene) 8(1): 113-117. Talon, B., Carcaillet, C., Thinon, M. (1998). 法国阿尔卑斯山区全新世林木上限变化的土壤炭屑学研究. 《物理地理与第四纪》(Géographie physique et Quaternaire) 52(2): 195-208.