Chrysophyte cyst-inferred variability of warm season lake water chemistry and climate in northern Poland: training set and downcore reconstruction

• Published in: Journal of paleolimnology 2015-01, Vol.53 (1), p.123-138
• Main Authors: Hernández-Almeida, I, Grosjean, M, Tylmann, W, Bonk, A
• Format: Article
• Language: English
• Subjects: bicarbonates; Calcite; calcium; climate; Climate Change; Climate variability; correlation; Earth and Environmental Science; Earth Sciences; electrical conductivity; environmental factors; Epilimnion; Freshwater; Freshwater & Marine Ecology; Geology; hydrochemistry; Lakes; mixing; Nitrogen; nitrogen content; Original Paper; Paleontology; Physical Geography; prediction; Seasons; Sediment samplers; Sedimentology; Sediments; Spring; summer; temperature; Turbidity; warm season; Water chemistry; Water column; Wind speed
• ISSN: 0921-2728; 1573-0417
• DOI: 10.1007/s10933-014-9812-4

Chrysophyte cyst assemblages from sediment trap and surface sediment samples of 50 lakes in northern Poland were related to environmental variables using multivariate numerical analyses (DCA, CCA). Water electric conductivity, total nitrogen, total phosphorous, turbidity, and cation and anion compositions (Ca²⁺, HCO₃⁻) accounted for significant and independent variations in the chrysophyte cyst assemblages. The first canonical axis was related to the gradient of Ca²⁺while the second axis was correlated with total nitrogen. A quantitative transfer function was then developed to estimate Ca²⁺(log₁₀transformed) from modern chrysophyte cyst assemblages using weighted-averaging regression with classical deshrinking. The bootstrapped regression coefficient ([Formula: see text]) was 0.68, with a root-mean square error of prediction of 0.143 (log₁₀units). The calibration model was applied to a varved sedimentary sequence (AD 1898–2010) from Lake Żabińskie, Masurian Lakeland (NE Poland). Observational data from this lake show that the Ca²⁺variability in the epilimnion depends on the efficiency of Ca²⁺scavenging by CaCO₃precipitation in early summer, which in turn is a function of water column stratification, temperature and the wind regime from late spring to early fall. The spring-fall wind regime drives the water column mixing. In Lake Żabińskie, cyst-inferred warm-season lake water Ca²⁺concentrations are significantly negatively correlated with calcite precipitation (CaCO₃concentrations in sediments; R = − 0.49, pₐdⱼ