Correlation between the Physicochemical Water Properties and the Morphological Characters of Lemna gibba L.

This study examined the correlation between physicochemical water properties and morphological characters of Lemna gibba L. based on field data from Serbia (South Morava, West Morava, Great Morava, and Danube catchments). Morphology was assessed using macro- (frond and turion number, frond dimensions, and their ratios) and micromorphological characters (epidermal cells and stomatal features). Correlations with water parameters (pH, EC, NO₃⁻, NO₂⁻, PO₄³⁻, SO₄²⁻, Cl⁻, Br⁻, and F⁻) were analyzed using the Pearson correlation coefficient and Canonical Correspondence Analysis (CCA). Pearson correlation analysis showed positive associations of Cl⁻ and NO₃⁻ concentrations with frond dimensions (width, length, and area), and negative associations with PO₄³⁻ concentration. The CCA identified Cl⁻, F⁻, and NO₃⁻ concentrations as key drivers, linked to reduced frond number, frond length-to-width ratio, and stomatal and guard cell dimensions. In contrast, higher Br⁻ concentrations were linked to increased frond size and adaxial epidermal cell area, while PO₄³⁻ was associated with greater guard cell width and stomatal density. These results provide insight into the uni- and multivariate influence of certain physicochemical water properties on the morphological variability of L. gibba.