Morpho-Anatomical Characteristics of Olive (Olea europaea L.) Trees Leaf as Bio-indicator of Cement Dust Air Pollution in Libya

Abstract

Comparisons were made between the anatomical and morphological changes in olive tree leaves from a site with relatively clean air (Al-Khadra area), and two sites (al-Khums and Zelatin) near to cement factories in the area east to Tripoli, Libya. Olive tree leaves exhibited marked variations in their morphological and anatomical characteristics, in relations to variations in the site cement dust air pollution load. Under high pollution load, leaf visible injuries were recorded. In addition, stomata appeared in higher density and smaller size than those of control. The anatomical characteristics of olive leaf including cuticle, epidermis, palisade tissue, mesophyll tissue, and elements of vascular cylinder (xylem and phloem) reflected the deteriorate effects of cement dust air pollutants, the subject which recommend their using as bio indicators.