Industrial air pollution, particularly cement dust, affects the leaf water status and resource utilisation and finally decreases primary production. Evaluating the relative water content (RWC), leaf mass per unit area (LMA), specific leaf area (SLA), and leaf water per unit area (LWA) helps selecting more tolerant species for dusty polluted areas. In this study, we compare two species of Quercus castaneifolia C.A.Mey and Carpinus betulus L. in a polluted site (PL) around a cement factory, and a unpolluted site (UPL) in Mazandaran province, Northern Iran. Ten individual trees of each species were tagged at each site, and twenty fully developed leaves were collected for further analysis and calculation. Based on the results, RWC and LWA were significantly lower in the PL site (61.0% and 0.0075 g·cm–2, respectively) compared to the UPL site (71.1% and 0.0114 g·cm–2, respectively) for Q. castaneifolia. However, no significant differences were observed in selected variables between PL and UPL sites for C. betulus. Among the studied variables, SLA was significantly higher in C. betulus (259.1 cm2 ·g–1) compared to Q. castaneifolia (189.8 cm2 ·g–1). Our results indicated that C. betulus responds better to dust pollution in terms of leaf water variables.
