In agreement with our hypothesis, CWMs were more strongly correlated to environmental variables than species composition, diversity, or functional diversity. Differences in anecic and endogeic earthworm community structure matched flood frequency. The distribution of earthworm traits varied among habitats in relation to changes in flooding frequency: poorly developed gravel bar soils most exposed to flooding were characterised by high abundance of small epigeic species and low abundance of large anecic species. We hypothesised that trait-based metrics would reveal clearer patterns than classical approaches. In addition to classical species-based metrics, such as species richness and Shannon diversity, species traits were used to calculate the community weighted means (CWMs) of traits and functional dispersion (FDis). We characterised the patterns of earthworm communities and species traits in the different habitats of a lowland restored floodplain in Switzerland. floods, river channelisation, floodplain restoration). Little is known about the diversity and ecology of earthworms in floodplains, as well as their response to natural and anthropic perturbations ( e.g. Studies characterising the paleoecological response to pollution allow pollution impacts to be tracked and distinguished from climate change. However, we caution researchers to be aware of this possibility when interpreting paleoecological records. We found a significant effect in only one case, an experiment in which N and P were added, suggesting that pollution-induced biases are limited. This raises the question: can pollution lead to changes in the testate amoeba paleoecological record that could be erroneously interpreted as a climatic change? To address this issue we applied testate amoeba transfer functions to the results of experiments adding pollutants (N, P, S, Pb, O 3) to peatlands and similar ecosystems. Peatlands around the world have been exposed to anthropogenic and intermittent natural pollution through the late Holocene. ![]() ![]() Peatland testate amoebae are widely used to reconstruct paleohydrological/climatic changes, but many species are also known to respond to pollutants. The performance of multi-proxy and single-proxy transfer functions should be further compared in paleoecological data. These results show new directions for paleoenvironmental research, 1) suggesting that it is possible to build good-performing transfer functions using presence/absence data, although with some loss of accuracy, and 2) supporting the idea that multi-proxy inference models may improve paleoecological reconstruction. The comparison of DWT and pH inferred from testate amoeba percentages and presence/absence data showed similar general patterns but differences in the magnitude and timing of some shifts. The best performing transfer functions overall for DWT were those based on combined testate amoebae percentages, bryophytes and vascular plants and, for pH, those based on testate amoebae and bryophytes. Bootstrapping cross-validation showing the best performing single-proxy transfer functions for both DWT and pH were those based on bryophytes. multi-proxy models and 2) assess the performance of presence/absence models. We developed and compared multiple transfer functions to infer peatland depth to the water table (DWT) and pH based on testate amoeba (percentages, or presence/absence), bryophyte presence/absence, and vascular plant presence/absence data from sub-alpine peatlands in the SE Swiss Alps in order to 1) compare the performance of single-proxy vs. Peatlands are widely exploited archives of paleoenvironmental change. rotunda (Penard 1890), describe three new species: N. We redefine Nebela tincta (Leidy) Kosakyan et Lara and N. We therefore revise the taxonomy of the group. We show here that small variations in test morphology that have been often overlooked by traditional taxonomy correspond to distinct haplotypes. Our goals were (1) to clarify the taxonomy and the phylogenetic relationships within this group, and (2) to evaluate if individual genotypes corresponded to specific morphotypes and the extent of phenotypic plasticity. We examined the relationship between morphological and genetic diversity within this species complex by combined analyses of light microscopy imaging and Cytochrome Oxidase Subunit 1(COI) sequences obtained from the same individual amoeba cells. ![]() ![]() The taxonomic validity of characters used to define species within this group is debated and causes confusion in studies of biogeography, and applications in palaeoecology. Nebela tincta–collaris–bohemica (Arcellinida) is a species complex of small to medium-sized (ca.100 μm) testate amoebae common in peat bogs and forest soils. Species identification by means of morphology is often problematic in protists.
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