Air pollution tolerance index and heavy metal bioaccumulation in selected plant species from urban biotopes

- Plantain, dandelion, black locust, birch may be used in heavy metal bioindication.
- The efficiency of heavy metal bioaccumulation depends on species and type of elements.
- The investigated plants may be useful in tackling atmospheric pollution.

This research was carried out on plants Taraxacum officinale, Plantago lanceolata, Betula pendula and Robinia pseudoacacia growing in urban biotopes with different levels of heavy metal contamination in the city of Dąbrowa Górnicza (southern Poland). Based on the pollution index, the highest heavy metal contamination was determined in the site 4 (connected with industry emitters) and 6 (high traffic). The metal accumulation index (MAI) values ranged within the biotopes in Dąbrowa Górnicza between 7.3 and 20.6 for R. pseudoacacia, 4.71-23.1 for P. lanceolata, 4.68-28.1 for T. officinale and 10.5-27.2 for B. pendula. Increasing tendency in proline content in biotopes connected with high traffic was found in the leaves of investigated plants (except R. pseudoacacia). Similar tendency was observed for ascorbic acid content in the foliage of the plants as well as in T. officinalle in stands connected industrial emission. Non-protein thiols content increased especially in the leaves of R. pseudoacacia in biotopes with high traffic emissions as well as in T. officinale in stands connected with industry. The mean values of APTI (Air Pollution Tolerance Index) within the city of Dąbrowa Górnicza for investigated plants were found in the following ascending order P. lanceolata < R. pseudoacacia < B. pendula < T. officinale. Among the investigated plants B. pendula and T. officinale may be postulated as appropriate plants in urban areas with considerable soil and air contamination, especially with heavy metals. The results indicate that species deemed tolerant according to APTI are suitable plants in barriers areas to combat atmospheric pollution.