Salt accumulation and effects within foliage of Tilia × vulgaris trees from the street greenery of Riga, Latvia

Lime trees (Tilia × vulgaris) in Riga's street greenery exhibit remarkable tolerance to salt pollution, accumulating NaCl concentrations up to 13,600/16,750 mg kg⁻¹ in foliage without nutrient imbalance. Despite this, salt disrupts leaf physiology by altering mesophyll vacuolar ionic composition—reducing K and Ca—and causing cellular swelling, which impedes transpiration. Degenerative cytoplasmic changes suggest indirect stress effects, revealing that while these trees endure dystrophic urban conditions, their leaf function is directly compromised by salt accumulation. The study used field material from Riga to analyze structural and ultrastructural injury via microscopy, linking salt allocation patterns to physiological impacts.

Cekstere, G., Osvalde, A., Elferts, D., Rose, C., Lucas, F., & Vollenweider, P. (2020). Salt accumulation and effects within foliage of Tilia × vulgaris trees from the street greenery of Riga, Latvia. Science of the Total Environment, 747, 140921. https://doi.org/10.1016/j.scitotenv.2020.140921