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Metabolomics - Useful Tool for Study of Plant Responses to Abiotic Stresses

Kráľová K., Jampilek J., Ostrovsky I.

Ecological Chemistry and Engineering. S

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2012

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Vol. 19, nr 2

133-161

EN

Abiotic stresses are produced by inappropriate levels of physical components of the environment and cause plant injury through unique mechanisms that result in specific responses. Metabolomics is a relatively new approach aimed at improved understanding of metabolic networks and the subsequent biochemical composition of plants and other biological organisms. The paper is focused on the use of metabolomics, metabolic profiling and metabolic fingerprinting to study plant responses to some environmental stresses (eg elevated temperature, chilling and freezing, drought, high salinity, UV radiation, high ozone levels, nutrient deficiency, oxidative stress, herbicides and heavy metals). Attention is also devoted to the effects of some environmental factors on plants such as high or low levels of CO2 or different levels of irradiance. Alterations of plants metabolites due to multiple abiotic stresses (drought-heat, drought-salinity, elevated CO2-salinity) are analysed as well. In addition, metabolomic approach to study plant responses to some artificial abiotic stresses, mechanical stress or pulsed electric field-induced stress is discussed. The most important analytical methods applied in metabolomics are presented and perspectives of metabolomics exploitation in the future are outlined, too.

PL

Stres abiotyczny wywołany przez niewłaściwe poziomy fizycznych komponentów środowiska powoduje zmiany w roślinach i poprzez specyficzne mechanizmy prowadzi do określonych odpowiedzi. Metabolomika jest stosunkowo nowym podejściem mającym na celu lepsze zrozumienie szlaków metabolicznych oraz skutków biochemicznych w składzie roślin i innych organizmów biologicznych. Artykuł skupia się na wykorzystaniu metabolomiki, profilowania metabolicznego i „fingerprintingu” metabolicznego do badania reakcji roślin na niektóre stresy środowiskowe (np. podwyższoną temperaturę, chłodzenie i zamrażanie, suszę, wysokie zasolenie, promieniowanie UV, duże stężenie ozonu, niedobór substancji odżywczych, stres oksydacyjny, herbicydy i wpływ metali ciężkich). Zwrócono także uwagę na wpływ niektórych czynników środowiskowych na rośliny, takich jak: wysokie lub niskie poziomy CO2 lub różne poziomy natężenia oświetlenia. Przeanalizowano również zmiany związane z kombinacjami abiotycznych czynników stresujących (susza - upał, susza - zasolenie, podwyższone stężenie CO2 - zasolenie). Omówiono też metabolomiczne podejście do badania reakcji roślin na stresy abiotyczne wywołane niektórymi sztucznymi czynnikami, stresem mechanicznym lub impulsowym polem elektrycznym. Zaprezentowano najważniejsze metody analityczne stosowane w metabolomice oraz nakreślono perspektywy wykorzystania metabolomiki.

2

Use of the Hilbert-Huang Transform for characterization of gassy sediments in Eckernförde Bay

Tęgowski J., Ostrovsky I., Zamaryka M.

Hydroacoustics

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2011

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Vol. 14

237-244

EN

The bottom top layer of the central part of the Eckernförde Bay (Germany) consists of soft muddy sediments containing free methane gas. Locations of gas bubbles trapped in the sediment and gas seeps visualised with hydroacoustic data have been reported. The main goal of our study was to examine whether it was possible, using a singlebeam echosounder with relatively high frequency of the transmitted signal (120 kHz), to detect echo properties that could be indicative of the occurrence of free gas in the bottom sediments. During three days of measurements organised by Leibniz Institute of Marine Sciences (IFM-GEOMAR) in Kiel (Germany), the acoustic data were collected from boards of r/v Polarfuchs and r/v Littorina. The Hilbert-Huang Transform was applied to detect ‘gassy’ anomalies in backscattered signals from the bottom. The transformer decomposes signal into finite and small number of Intrinsic Mode Function (IMF) components with time-dependent amplitudes and frequencies. Certain IMF components carry information on variability of geoacoustic parameters, which can be indicative of presence of gas bubbles in the acoustically penetrated sediment as well as in the water column. Based on the shape of the echo signal envelope and its fading with range we characterized the signal attenuation in areas where gas was present. The rapid increase in acoustical wave attenuation in areas of intensive gas ebullition demonstrates good applicability of the method proposed.

3

The acoustic evidence for gas bubbles in the lake Kinneret sediments

Tęgowski J., Ostrovsky I., Zamaryka M.

Hydroacoustics

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2010

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Vol. 13

261-268

EN

The changes in gas content of bottom sediments are associated with rapid alterations of the ambient conditions (climate change, eutrophication, water level fluctuation, etc). In this paper we present results of acoustical measurements of sound scattering at gassy sediments in the subtropical Lake Kinneret (Sea of Galilee), where the 120 kHz single beam echosounder for bottom recognition was used. Measurements were carried out over a 10-year period along 14 standard transects. The echo parameterization method was applied to study acoustical features of bottom deposits and their variability in relation to sedimentary content of gas bubbles. Particularly, we examined the influence of water level fluctuations, affecting the presence of gas bubbles in the surface sediments on sound scattering and echo envelope parameters (spectral, wavelet, fractal, statistical and energetic). Presented results indicate the usefulness of the proposed method of backscattered signals processing for monitoring of the seafloor features.