Evaluating anatomical and biochemical responses to cement dust pollution in Quercus castaneifolia C.A. Mey. and Zelkova carpinifolia (Pall.)

Understanding how plants respond to industrial pollutants is crucial for assessing environmental impacts and developing effective management strategies. This study focused on the structural and biochemical adaptations of Quercus castaneifolia and Zelkova carpinifolia in response to cement dust pollution, which poses a significant environmental risk and adversely affects plant growth. We investigated structural changes in leaves and analyzed key biochemical markers in trees growing near a cement factory in Neka city, Mazandaran province, Iran, to examine the defense mechanisms these species use against dust pollution. Our results demonstrated notable anatomical adaptations in both species, including increased druse crystals and sclerified parenchyma cells. Additionally, Q. castaneifolia leaves showed wall collapse of xylary vessel elements under dust exposure. Biochemically, we observed elevated phenylalanine ammonia-lyase (PAL) activity and higher concentrations of phenolic compounds and lignin in leaves from polluted sites. While Q. castaneifolia exhibited higher PAL activity, Z. carpinifolia showed greater levels of phenolics and lignin, alongside more pronounced anatomical changes. These findings highlight species-specific defense strategies and resilience to cement dust pollution. The study underscores the importance of integrating both anatomical and biochemical parameters in ecological assessments and suggests that environmental management strategies should account for species-specific responses to pollution.