CONSIDERATIONS ON THE INFLUENCE OF ATMOSPHERE POLLUTANTS ON SOME SPECIES OF CULTIVATED AND SPONTANEOUS LIGNEOUS PLANTS

6th International Scientific Conference - SGEM2006, www.sgem.org, SGEM2006 Conference Proceedings/ ISBN: 954-918181-2, June 12-16, 2006, Vol. 2, 35-42pp

ABSTRACT

We have studied 15 species of ligneous plants angyosperms, spontaneous and cultivated ones – in areas adjacent to industrial platforms: Borzeşti (Bacău county), Bicaz and Taşca (Neamţ county) - Romania; in the first case, the noxious substances are mainly gaseous (sulphur dioxide, chlorine, ammoniac), but also solid (carbon black, soot); in the other two cases, the noxious substances are mainly solid ones (lime or cement powders prone to sedimentation). Our investigations have focused on observations concerning species of ligneous plants in various phenophases, the state of the leaf surfaces and histo – anatomical changes of the leaf under the influence of the above-mentioned atmosphere pollutants.In agreement with the results of the experiences performed by various researchers, using various concentrations of several noxious substances on herbal and ligneous species, whatever the type of noxious substance may be, the cyto-histological changes in the leaf are almost the same, phenotypising as chlorotic and necrotic spots; in the later case, the structure of all leaves is severely altered, which leads to the death and fall of the photo-assimilating organ and ultimately to the death of the entire plant.The histo-anatomical changes induced by the (gaseous and solid) atmosphere pollutants on the lamina have been observed in protecting tissues, assimilator tissues (the palisade layer and the lacunose tissue), vascular and mechanical tissues. Some leaves have presented disorders in all the component tissues, while in others, the structure changes have only appeared in part of the lamina.

Keywords: ligneous plants, atmosphere pollutants, morphological and histo-anatomical changes