Publication details
Ecology of testate amoebae in mires of the Western Carpathians and development of a transfer functions for paleoecological reconstructions
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| Year of publication | 2014 |
| Type | Conference abstract |
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| Citation | |
| Description | In the last decades testate amoebae became a valuable proxy for paleoreconstructions, especially as indicators of past lake and mire hydrology. To date, the greater part of paleoecological studies has been carried out on ombrotrophic mires worldwide. On the contrary, only a few studies have focused on groundwater-fed fens, where these organisms have also been used for pH inference. We investigated the relationship between testate amoebae communities, species composition of vegetation and environmental factors along the complete poor-rich gradient in mires of the Western Carpathians. The resulting data were then used as a base for transfer functions development. Testate amoebae communities from 22 mires (32 sites) were collected. The effect of water chemistry, depth to the water table (DWT), Ellenberg indicator values (EIVs) and vegetation composition was tested using redundancy analyses. The major variation in testate amoebae species data was related to the poor-rich gradient (represented either by EIV soil reaction or by water pH), while the second most important environmental factor controlling the species composition of communities was DWT. For these two significant environmental factors the transfer function models were constructed using jackknife cross-validation. Performance of the models was improved by selectively removing rare species and outlier samples from the data set. The best transfer function models allow for reconstructions of environmental conditions in mires of the Western Carpathians from fossil testate amoebae species data with prediction error of ±0.56 values for pH (PLS, 5 components) and of ±7.05 cm for DWT (WA-PLS, 2 components). Our results are generally consistent with previous studies on testate amoebae ecology from other regions, but contrary to most of them they describe species composition changes along the complete pH gradient. The strong correlation between pH and testate amoebae species composition highlights the importance of these unicellular organisms in paleoecology. |