Eco-fingerprinting of the dinoflagellate <Emphasis Type="Italic">Borghiella dodgei</Emphasis>: experimental evidence of a specific environmental niche |
| |
Authors: | Giovanna Flaim Eugen Rott Rita Frassanito Graziano Guella Ulrike Obertegger |
| |
Institution: | 1.IASMA Research and Innovation Centre-Fondazione Edmund Mach- Environment and Natural Resources Area,Michele all’Adige,Italy;2.Institute of Botany, WG Hydrobotany,University of Innsbruck,Innsbruck,Austria;3.Department of Physics,University of Trento,Povo,Italy |
| |
Abstract: | In Lake Tovel, an oligotrophic and weakly stratified lake, the dinoflagellate Borghiella dodgei Moestrup, Hansen et Daugbjerg, showed a peculiar spatial–temporal pattern with highest abundances in the bottom of the shallow
side bay (4 m) along with remarkable abundance variations from year to year. We investigated B. dodgei’s growth in laboratory cultures and related results to their implication for bloom formation. B. dodgei was cultivated under different temperature, nutrient and light conditions. Growth rates, cell biovolume, cyst formation and
pigment and mycosporine-like amino acids (MAAs) concentrations were determined. Experiments showed that this alga (i) had
higher growth rates at low temperatures (<7°C) and high irradiance levels (~250 μmol m−2 s−1), (ii) produced higher yields with organic supplements such as peptone, (iii) did not grow in the dark even with organic
supplements, (iv) survived for long periods without a light source, (v) synthesised MAAs, (vi) showed an increase in cell
volume with nutrient shortage and increasing temperatures (>7°C) and (vii) had high encystment rates with temperatures >7°C.
These laboratory fingerprints allowed us to construct a theoretical model defining the species’ niche. Borghiella needed a mixture of low temperatures, high irradiance levels and sufficient quantities of dissolved organic nitrogen to form
blooms. Such a strict combination was probably a transient situation and occurred in oligotrophic Lake Tovel only in early
summers followed by heavy spring rains. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|