Indici di valutazione del grado di inquinamento in area urbana

Pollution levels indexes in urban areas. Anatomical, morphological and physiological leaf traits of Quercus ilex L., Quercus pubescens Willd., Quercus cerris L., Quercus robur L. and Platanus hybrida Brot. were analysed to evaluate plant response to pollution effects, a feature which may have considerable impact on their role as bioindicators and bioaccumulators of contaminants. These species are largely employed for green street forniture in the city of Rome. The analysis of variance (ANOVA) indicated that specific leaf area (SLA), leaf mass area (LMA), leaf density (LTD) and leaf thickness (LT) were the most representative leaf traits discriminating between two gropups (group 1 = high pollution levels; group 2 = low pollution levels). Box and whisker plots showed differences among leaf traits. SLA, LMA, LTD and LT might be considered indexes of pollution levels in urban areas. Lastly the use of plant species, particularly Quercus ilex, as "green traps" in urban areas was considered.