| Autor: |
Vítek P; Global Change Research Institute of the Czech Academy of Sciences, Bělidla 986/4a, 603 00, Brno, Czech Republic. vitek.p@czechglobe.cz., Ascaso C; Museo Nacional de Ciencias Naturales, CSIC, c/ Serrano 115 dpdo., 28006, Madrid, Spain., Artieda O; Departamento Biología Vegetal, Ecología y Ciencias de la Tierra, and IACYS, Universidad de Extremadura, 10600, Plasencia, Spain., Casero MC; Museo Nacional de Ciencias Naturales, CSIC, c/ Serrano 115 dpdo., 28006, Madrid, Spain., Wierzchos J; Museo Nacional de Ciencias Naturales, CSIC, c/ Serrano 115 dpdo., 28006, Madrid, Spain. |
| Abstrakt: |
Raman imaging allows one to obtain spatially resolved chemical information in a nondestructive manner. Herein, we present analytical aspects of effective in situ and in vivo Raman imaging of algae and cyanobacteria from within their native rock habitats. Specifically, gypsum and halite inhabited by endolithic communities from the hyperarid Atacama Desert were analyzed. Raman imaging of these phototrophic colonization reveals a pigment composition within the aggregates that helps in understanding some of their adaptation strategies to survive in this harsh polyextreme environment. The study is focused on methodical aspects of Raman imaging acquisition and subsequent data processing. Point imaging is compared with line imaging in terms of their image quality, spatial resolution, spectral signal-to-noise ratio, time requirements, and risk of laser-induced sample alteration. The roles of excitation wavelength, exposure time, and step size of the imaging grid on successful Raman imaging results are also discussed. Graphical abstract. |
