Dinoflagellate cysts in surface sediments

<p>Surface sediments at 439 sites throughout the North Atlantic Ocean and adjacent seas have been analyzed for dinoflagellate cysts in order to establish a reference database from which paleoenvironmental transfer functions can be developed. Laboratory procedures and systematics were standardized in order to avoid bias introduced by the selective loss of taxa and to facilitate site to site comparison. 371 sites were retained to develop the database that includes 41 taxa, some of which were grouped using morphological and/or ecological criteria. 27 taxa were retained for statistical purposes. Distribution maps of these latter taxa have been plotted on the basis of their relative abundance. Principal component analyses were performed in order to describe the distribution of assemblages. The relation between the assemblages, as well as the relative abundance of individual taxa, and selected sea-surface parameters are illustrated. The parameters which were considered include temperature and salinity for winter (February) and summer (August) together with the duration of sea-ice cover. Transfer functions using the best analogue method have been tested with a view to reconstruct past sea-surface parameters. Validation procedures on this transfer function demonstrate that more than 95% of the reconstructions are included within the interannual variability of modern sea-surface conditions. Therefore, these transfer functions give accurate results and can be applied to reconstructing paleo–temperatures and –salinities from analogous assemblages in Quaternary sedimentary sequences.
Protoperidinium stellatum (Wall in Wall &amp; Dale, 1968) Head, comb. nov. (basionym &#61; Peridinium stellatum) is proposed as new, and Algidasphaeridium? minutum var. cezare de Vernal et al., 1989 ex de Vernal et al. is newly validated.</p>

在北大西洋海域及其相邻海域的439个地点采集的表层沉积物中，对隐藻囊进行了分析，旨在建立一个参考数据库，据此可以开发古环境转换函数。为了规避因分类单元的选择性丢失而引入的偏差，并促进站点间的比较，实验室程序和分类学方法得到了标准化。保留了371个地点的数据以构建包含41个分类单元的数据库，其中一些分类单元根据形态学和/或生态学标准进行了分组。保留了27个分类单元进行统计分析。基于这些后者的相对丰度绘制了分布图。通过主成分分析描述了群落分布。展示了群落之间的关系以及单个分类单元的相对丰度与选定海表参数之间的关系。考虑的参数包括冬季（二月）和夏季（八月）的温度和盐度，以及海冰覆盖持续时间。使用最佳类比法测试了转换函数，以期重建过去的海表参数。对这一转换函数的验证程序表明，超过95%的重建结果包含在现代海表条件年际变率的范围内。因此，这些转换函数能够提供准确的结果，并可应用于从第四纪沉积序列中的类似群落中重建古温度和古盐度。提出Protoperidinium stellatum（Wall in Wall & Dale, 1968）为新的分类，并将Algidasphaeridium? minutum var. cezare de Vernal et al., 1989 ex de Vernal et al.重新验证。