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Simultaneous component analysis as an interesting preliminary data analysis method in GC-MS – An example of headspace screening of Polish grasses

Wróbel-Szkolak Joanna, Cwener Anna, Pietraś Rafał, Komsta Łukasz

Acta Chromatographica

2024

Vol. 36, no. 1

52--58

70 species of grasses family (Poaceae), coming from genera: Agrostis, Alopecurus, Anthoxanthum, Apera, Arrhenatherum, Avena, Brachypodium, Briza, Bromus, Calamagrostis, Corynephorus, Cynosurus, Dactylis, Danthonia, Deschampsia, Digitaria, Echinochloa, Elymus, Eragrostis, Festuca, Glyceria, Helictotrichon, Hierochloe, Holcus, Hordeum, Koeleria, Leymus, Lolium, Milium, Molinia, Nardus, Panicum, Phalaris, Phleum, Phragmites, Poa, Saccharum and Setaria, collected mostly from natural stands in Poland during 2020 season, were subjected to GC-MS fingerprinting of headspace volatile fraction above dried material. Obtained mass spectrometry data were analyzed by means of principal component analysis (PCA) and hierarchical cluster analysis (HCA). Five species: Glyceria maxima (Hartm.) Holmb., Lolium multiflorum Lam., Hordeum jubatum L., Bromus tectorum L. and Bromus secalinus L. were identified as outliers, which is consistent with our earlier analysis by thin layer chromatography. These species deserve further look and their outliance is orthogonal to coumarin content, which was independently observed for odorant species of grasses.

The use of diatoms to assess the water quality in the Wisłoka River in the town of Dębica and the surrounding area

Noga T., Stanek-Tarkowska J., Peszek Ł., Pajączek A., Kochman-Kędziora N., Ligęzka R.

Oceanological and Hydrobiological Studies

2016

Vol. 45, No. 2

191--201

The objective of this work was to examine the water quality using three diatom indices SPI, GDI and TDI. The material for the study was collected during four seasons from autumn 2010 to summer 2011, from four sampling sites located on the Wisłoka River, in the town of Dębica and the surrounding area. The Wisłoka at all selected sites was characterized by alkaline or close to neutral pH (pH 6.5-7.7). Electrolytic conductivity ranged from 364 to 480μS cm-1. The Wisłoka at the selected sites in the urban area and in the surrounding areas was characterized by high diatom species richness. The total of 238 taxa from 53 genera were recorded, of which the most numerous were: Nitzschia (44), Navicula (33) and Gomphonema (12). Achnanthidium minutissimum var. minutissimum, Amphora pediculus, Navicula gregaria, N. lanceolata, and Nitzschia dissipata ssp. dissipata were usually the dominant species. Chemical parameters indicated very good quality of water. However, the diatom indices used to assess the water quality, classified the studied water into a group corresponding to quality class III or IV.

Subfossil chydorid taxa and assemblages from lake sediments in Poland and Finland with special reference to climate

Sarmaja-Korjonen K., Szeroczyńska K., Gąsiorowski M.

Studia Quaternaria

2003

Vol. 20

25-34

In this study we compared chydorid cladoceran (Chydoridae) taxa and assemblages from sediments of 6 Polish and 6 Finnish lakes and investigated if the difference in climate of these two countries can be detected in the cladoceran data. The data were analysed in terms of 1) average relative proportions of chydorid taxa during the history of each lake and by 2) redundancy analysis (RDA) to explain the present effect of environmental variables (altitude, area, maximum depth, mean annual temperature, mean summer temperature and length of the growing season) on species abundances. The redundancy analysis (RDA) enabled us to distinguih groups of taxa 1) with a high thermal preference 2) associated with small, cold-water lakes and 3) associated with shallow lakes. There are clear differences in the dominant chydorid taxa and in the relative proportions of many other chydorid taxa between the two countries since the end of the last glaciation. Although these differences first of all appear to reflect the climatic difference, the influence of many other environmental factors, controlling the living conditions of particular chydorids have been raised and considered. Further studies with larger data are needed before the role of climate can be reliably separated from other elements of environment.