Core-top carbon isotope measurements of dinoflagellate cysts

The here deposited data represents stable carbon isotope measurements of dinoflagellate cyst (dinocyst) taxa isolated from core-top sediments. Carbon isotope data were generated using laser-ablation / nano-combustion / gas chromatography isotope ratio mass spectrometry (LA-nC-GC/IRMS) and each measurement represents 3-7 individual, hand-picked, dinocysts. A more detailed description of sample and data processing can be found here: https://bg.copernicus.org/preprints/bg-2022-118/ (updated with final version once available). The data were used to test dependency of carbon isotope fractionation to environmental parameters, most notably CO2, in order to construct a pCO2 proxy based on dinocyst carbon isotope fractionation. Carbon isotope data for five species (Operculodinium centrocarpum, Spiniferites ramosus, Spiniferites elongatus, Spiniferites mirabilis and Impagidinium aculeatum are presented, from 19 localities in the Atlantic Ocean and Mediterranean sea (listed in the data files), as well as pre-industrial material from the North Atlantic Ocean (ENAM9606, 55.650 ºN, -13.985 ºE). Three data files (summary and raw measurements for the core-tops and pre-industrial samples) are added. The summary file contains the data to calculate carbon isotope fractionation (ep) for each core-top sample and species (average raw and corrected dinocyst d13C, d13C of dissolved inorganic carbon (DIC), temperature) and the environmental parameters (pCO2, NO3, PO4, Si, temperature, salinity, alkalinity) used to compare to the dinocyst carbon isotope data. The raw measurement data file for the contains the sample identifier which links to the summary file, the species and signal-size and d13C value for each of the 949 individual measurements and similar file is included for the pre-industrial samples from ENAM9606 (n = 137). A signal-size dependent correction is applied based to eliminate small drift induced by background C (d13C adjusted). After this step, a disqualifier is given if the data is excluded based on too low signal intensity (below cut-off / BCO) or represents a statistical outlier within the d13C population of that specific sample and species (OUT). The adjusted d13C data without disqualifiers is included in the 'corrected d13C' and used in the summary file and statistical tests (see also https://bg.copernicus.org/preprints/bg-2022-118/). Species abbrevations: Operculodinium centrocarpum "Ocen", Spiniferites ramosus "Sram", S. elongatus, "Selon", S. mirabilis "Smira", Impagidinium aculeatum "Iacul".本次提交的数据为从岩芯表层沉积物中分离得到的沟鞭藻囊孢（dinocyst）类群的稳定碳同位素测量结果。本次碳同位素数据采用激光剥蚀/纳米燃烧/气相色谱同位素比值质谱仪（LA-nC-GC/IRMS）完成，单次测量对应3~7个经手工挑选的单个沟鞭藻囊孢。关于样品与数据处理的详细说明可参见：https://bg.copernicus.org/preprints/bg-2022-118/（最终版发布后将更新此链接）。 本数据集用于验证碳同位素分馏对环境参数（尤以二氧化碳（CO₂）为代表）的依赖关系，以期基于沟鞭藻囊孢的碳同位素分馏构建二氧化碳分压（pCO₂）代用指标。本次数据集包含5个物种的碳同位素数据：多甲藻属（Operculodinium centrocarpum）、刺甲藻属（Spiniferites ramosus）、伸长刺甲藻（Spiniferites elongatus）、奇异刺甲藻（Spiniferites mirabilis）以及具刺盖藻（Impagidinium aculeatum），采样点覆盖大西洋与地中海的19个站位（详见数据文件），同时包含北大西洋的工业革命前沉积物样品（站位ENAM9606，坐标55.650°N，-13.985°E）。 本次共提交3个数据文件，分别为岩芯表层沉积物与工业革命前样品的汇总数据及原始测量数据。 汇总文件包含用于计算各岩芯表层沉积物样品及对应物种的碳同位素分馏系数（εp）所需的数据，包括沟鞭藻囊孢的原始与校正后平均δ¹³C值、溶解无机碳（DIC）的δ¹³C值及温度数据；同时包含用于与沟鞭藻碳同位素数据对比的环境参数，即二氧化碳分压（pCO₂）、硝酸盐（NO₃⁻）、磷酸盐（PO₄³⁻）、硅（Si）、温度、盐度与碱度。 岩芯表层沉积物的原始测量数据文件包含与汇总文件对应的样品标识符、各次测量的物种信息、信号强度及δ¹³C值，共949次单个囊孢测量数据；同时配套提交了ENAM9606站位工业革命前样品的原始测量数据文件（样本量n=137）。 研究人员采用基于信号强度的校正方法，以消除背景碳引发的微小漂移（已完成δ¹³C值校正）。 校正完成后，若数据因信号强度过低（低于截断值/BCO），或属于对应样品与物种的δ¹³C统计异常值（标记为OUT），则会被标记为无效数据。 经校正且无无效标记的δ¹³C数据将归入"校正后δ¹³C"数据集，用于汇总文件计算与统计检验（详细说明参见https://bg.copernicus.org/preprints/bg-2022-118/）。 物种缩写对应关系如下：多甲藻属（Operculodinium centrocarpum）记为"Ocen"，刺甲藻属（Spiniferites ramosus）记为"Sram"，伸长刺甲藻（Spiniferites elongatus）记为"Selon"，奇异刺甲藻（Spiniferites mirabilis）记为"Smira"，具刺盖藻（Impagidinium aculeatum）记为"Iacul"。