Morphological parameters of stomata and the content of photosynthetic pigments in leaves of common reed (Рhragmites australis (Сav.) Trin. еx Steud.) under the influence of mines in the Kryvyi Rih city

Abstract

The impact of anthropogenic activity on the biosphere is growing every year. Aquatic ecosystems are a component of the natural environment very sensitive to anthropogenic impact. Therefore, the study of the mechanisms of resistance of aquatic organisms, including macrophytes, to pollution of water bodies is becoming increasingly important. In order to study the impact of the mining industry on higher aquatic vegetation, we determined the size and number of stoma and the content and ratio of chlorophylls in the leaves of common reeds (Phragmites australis (Cav.) Trin. Ex Steud.) from different parts of the Saksagan River; return (rain and melt) water, in the place of release of return (rain and melt) water and below the release of return (rain and melt) water near the mine «Ternivska». The number and size of the closing cells of the stoma were determined on the prints of the epidermis on the abaxial side of the leaves of plants, which were examined under a microscope «Ulab XY-B2TLED» at a magnification of 20 and photographed with a digital camera «Sciencelab T500 5/17M» connected to it. The content of chlorophyll (Chl а, Chl b and total chlorophyll) was determined by the method of Wintermans J. F. G. M., De Mots A. (1965) in ethanolic extracts of reed leaves using a spectrophotometer «Ulab 102 Spectrophotomet». Mathematical processing of the results was performed by the variational-statistical method. All calculations were performed using the software package Statistica 6.0. It was found that the stoma on the abaxial side of common reed leaves from areas in place and below the release of return (rain and melt) water differ significantly in morphometric parameters from the stoma of plants from the area above the release of return (rain and melt) water. There was an increase in the density of stoma per unit area of the leaf in the leaves from the study areas with a greater impact of the activity of the mine «Ternivska». Changes in the content of chlorophyll and the ratio of chlorophyll forms (Chl a/Chl b) in the leaves of P. australis depending on the conditions of influence of the mine activity «Ternivska» were recorded. Changes in some indicators of the anatomical structure of leaves in the direction of xeromorphism and rearrangement of the photosynthetic apparatus in urban conditions can be considered as an adaptive response of common reed to environmental pollution.