Anatomical and ultrastructural alterations in Pinus pinea L. needles treted with simulated sea aerosols

The effects of sea pollution by surfactants on coastal vegetation have been studied for several decades now in a number of European and non European regions. The damage is normally attributed to an excessive absorption of salts as a result of the action of the surfactants which lower the surface tension of the droplets of aerosol and make it easier for them to penetrate the stomata. Yet researchers have also discussed the possibility that surfactants may have a direct phytotoxic effect. This paper illustrates an anatomical and ultrastructural study of Pinus pinea L. needles treated with simulated sea aerosol for brief exposure periods. The results of this study confirm that anionic and non-ionic surfactants are directly toxic and affect mainly the stomatal apparatus, including both the epistomatal network and the guard cells and substomatal cells .