Determination of (palaeo-)ecological preferences of dinoflagellates by applying Detrended and Canonical Correspondence analysis to Late Pliocene dinoflagellate cyst assemblages of the south Italian Singa section

Abstract

The statistical methods Detrended Correspondence Analysis (DCA) and Canonical Correspondence analysis (CCA) are used to determine the ecological preferences of dinoflagellate cyst species from the upper part of the Italian Singa section (2.8-2.2 Ma). Using DCA, gradients that have major influence on the species composition have been determined. By using existing environmental information for the Singa section based on planktic foraminifera, such as Sea Surface Temperature (SST), Sea Surface Productivity (SSP) and stable oxygen isotopes as well as the ecological information of extant dinoflagellate cysts, these gradients are interpreted in terms of temperature, inshore-offshore trends and evolutionary and other time-related gradients. Using CCA, the position of species optima in this dataset in relation to these temperature, inshore-offshore and evolutionary and other time related gradients are determined. For the studied period, the extinct species Melitasphaeridium pseudorecurvatum and Acritarch sp. B are related to temperate to warm intervals. Amiculosphaera umbracula is related to the cooler older intervals whereas Nematosphaeropsis rigida is related to the warmer younger intervals.