Abstract Here we report and compare results on planktic foraminiferal assemblages extracted with five disaggregation techniques: acetic acid, H2O2 at 10% and 25% concentration, neosteramina, and liquid N2. The aim is to estimate whether these laboratory procedures can affect the pristine assemblages or add secondary dissolution effects. We apply these five methods on three samples with different carbonate content from the early Eocene Tethyan Terche section (northeast Italy). For each method we assess: (1) the treatment effectiveness in relation to time required to successfully extract planktic foraminiferal tests and preservation; (2) the degree of dissolution through the analyses of three well-known dissolution proxies including the fragmentation index, the planktic benthic ratio and the weight percent coarse fraction; (3) changes in planktic foraminiferal assemblages through genera and species absolute abundances and the evaluation of multiple species diversity indices. Our data demonstrate that acetic acid and neosteramina treatments are the most effective methods as they represent the only ones capable in disaggregating the samples with higher CaCO3 content whereas liquid N2 revealed to be the best treatment to adopt for samples with low CaCO3 content. The best-preserved foraminiferal specimens derive from the acetic acid and neosteramina treatments. Nonetheless, the acetic acid along with H2O2 treatments, at both concentrations, can impact planktic foraminiferal assemblages affecting the diversity or species abundances. Dissolution of planktic foraminifera shows a complex relationship with the initial carbonate content (CaCO3%) of the samples and with the different dissolution susceptibility of the species that can differ according to the laboratory procedures.

中文翻译：

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不同的提取技术会影响浮游有孔虫组合吗？始新世早期案例研究

摘要 在这里，我们报告并比较了用五种分解技术提取的浮游有孔虫组合的结果：乙酸、浓度为 10% 和 25% 的 H2O2、neosteramina 和液态 N2。目的是估计这些实验室程序是否会影响原始组合或增加二次溶解效应。我们将这五种方法应用于来自早始新世 Tethyan Terche 剖面（意大利东北部）的三个不同碳酸盐含量的样品。对于每种方法，我们评估： (1) 与成功提取浮游有孔虫测试和保存所需时间相关的治疗效果；(2) 溶解度通过三个众所周知的溶解代理分析，包括破碎指数、浮游底栖生物比和粗粒重量百分比；(3) 浮游有孔虫组合通过属和种绝对丰度和多个物种多样性指数的评价的变化。我们的数据表明，醋酸和 Neosteramina 处理是最有效的方法，因为它们是唯一能够分解具有较高 CaCO3 含量的样品的方法，而液态 N2 显示是对 CaCO3 含量较低的样品采用的最佳处理方法。保存最完好的有孔虫标本来自醋酸和新斯特拉米纳处理。尽管如此，两种浓度的乙酸和 H2O2 处理都会影响浮游有孔虫组合，从而影响多样性或物种丰度。