Quantifying species–environment relationships in non-marine Ostracoda for ecological and palaeoecological studies: Examples using Iberian data

With current concerns over issues such as global warming, the use of palaeoecological data to reconstruct past environments has gained a special significance, but much of the work on ostracod ecology and paleoecology has been qualitative in nature, or on a site-specific rather than integrated, regional basis. Furthermore, ostracod ecological relationships are complex, with each species occupying a multidimensional niche, and a range of statistical techniques can be employed to establish the significance of different environmental variables on species distribution. loy logistic regression (LR) and canonical correspondence analysis (CCA) to define ostracod species niches and assemblage response to environmental gradients, using a modern dataset of 465 ostracod samples from the eastern Iberian Peninsula. In addition to these ecological analyses, we develop ostracod-based transfer functions for the quantitative reconstruction of past environmental change from a modern regional data-set of non-marine ostracod and limnological data, by means of weighted averaging (WA) regression and calibration. Examples cited are primarily from modern and fossil ostracod samples from Iberian water bodies. sults suggest that water chemistry (solute composition and concentration) and temperature are the factors to which non-marine ostracod species respond in a more clear and consistent way. Species–environment relationships modelled using the transfer-function approach of WA are strong for the above-mentioned variables, and therefore these models may be of great help in palaeoenvironmental reconstructions.