Abstract

Quaternary palynology commonly requires the use of acids such as hydrofluoric acid (HF), sulphuric acid (H₂SO₄), and hydrochloric acid (HCl) to extract pollen grains and spores. In some countries, restricted access to these acids makes fossil pollen studies challenging. Here, we propose an alternative pollen processing technique that does not require the use of acids. The methodology is mainly based on the use of potassium hydroxide (KOH) as a humic acid remover, sodium metaphosphate (NaPO₃) and sodium pyrophosphate (Na₄P₂O₇) as a deflocculant, and zinc chloride (ZnCl₂) as a precursor for the flotation of the pollen grains. The techniques were tested and compared with a well-established and widely applied technique in palynology laboratories, which requires acids. For testing the techniques, 0.5 cm³ of samples from three different sedimentary environments (peat, lake, and swamp) in Brazil were used. The technique using sodium metaphosphate was successful because the structure of the fossil pollen grains and spores showed no retention of extraneous organic matter, thus facilitating their morphological identifications. The pollen grain concentrations for the sample were equivalent to the treatment with acids. This protocol was developed to allow broader, safer, and cheaper access to palynological research, as the impediments represented by restrictions on reagent controls do not apply. This protocol also respects environmental protection policies.

摘要

第四纪孢粉学通常需要使用酸如氢氟酸 (HF)、硫酸 (H ₂ SO ₄ ) 和盐酸 (HCl) 来提取花粉粒和孢子。在一些国家，限制获得这些酸使化石花粉研究具有挑战性。在这里，我们提出了一种不需要使用酸的替代花粉加工技术。该方法主要基于使用氢氧化钾 (KOH) 作为腐植酸去除剂、偏磷酸钠 (NaPO ₃ ) 和焦磷酸钠 (Na ₄ P ₂ O ₇ ) 作为抗絮凝剂以及氯化锌 (ZnCl ₂) 作为花粉粒浮选的前体。对这些技术进行了测试，并与孢粉学实验室中成熟且广泛应用的技术进行了比较，该技术需要酸。用于测试技术，0.5 cm ³使用了来自巴西三种不同沉积环境（泥炭、湖泊和沼泽）的样品。使用偏磷酸钠的技术是成功的，因为化石花粉粒和孢子的结构显示没有外来有机物的保留，从而有助于它们的形态鉴定。样品的花粉粒浓度与酸处理相当。该协议旨在允许更广泛、更安全和更便宜地获得孢粉学研究，因为试剂控制限制所代表的障碍不适用。该协议还尊重环境保护政策。