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• Elemental concentration in deposited dust on urban tree leaves depending applied washing method

  45-52

  Vanda Molnár

  Views:

  225

  In our study, the concentrations of elements were determined in leaves and deposited dust of Quercus robur and Celtis occidentalis which were washed with distilled water, rainwater and tap water. According to our results, each washing solutions had a significant effect on the elemental concentrations in the foliage dust. The highest concentrations of aluminum, chromium, copper, iron, manganese and zinc were detected in the foliage dust which was washed down with rainwater. The highest strontium and barium concentrations were found in the foliage dust which was washed down with tap water. We observed chromium and manganese accumulation in Q. robur leaves, while the concentrations of barium, copper and strontium were the highest in C. occidentalis leaves. Our results demonstrated the effect of rainwater on tree leaves which phenomenon occurs naturally. Rainwater may wash down the dry deposited foliage dust from the leaf surface, but it also delivers a certain concentration of elements through wet deposition.

• Environmental monitoring using linden tree leaves as natural traps of atmospheric deposition: a pilot study in Transilvania, Romania

  24-35

  Mihály Braun

  Zita Margitai

  Albert Tóth

  Martine Leermakers

  Views:

  115

  Atmospheric pollution caused by toxic elements is an emerging problem of concern. Tree leaves have been widely used as indicator of atmospheric pollutions and they are effective alternatives to the more usual biomonitoring methods. Tree leaves can be used as natural traps of atmospheric deposition. Elemental composition of dust deposited onto leaf surfaces can be used to characterize the urban environment. A pilot survey including 16 Romanian settlements was carried out in order to evaluate the characteristics and sources of air pollutants. Tree leaves (Tilia tomentosa, Tilia cordata, Tilia platyphyllos) were collected and used for the measurements. Elemental analyses were carried out by ICP-OES and ICP-MS. Principal component and discriminant analyses were used to characterizing and estimating the level of pollution. Settlements were grouped on the basis of discriminant function values. Multivariate comparison of chemical data ordered the settlements into 3 main groups, which showed a systematic geographic distribution.