Reclamation of fly ash dump diminishes the metal accumulation and improves the photosynthetic function of orchid Listera ovata

Abstract

The results of studying the metal accumulation and photosynthetic function in the orchid Listera ovata (L.) R. Br., growing on the fly ash dump of the Verkhnetagilskaya Thermal Power Station (VTTPS, Middle Urals, Russia) are presented. A comparative analysis of two L. ovata populations from the non-reclaimed and partly reclaimed fly ash dumpsites was carried out. It was shown that the partial reclamation of the fly ash dump by applying clay soil increased heavy metal total content in the substrate. At the same time, the proportion of mobile forms and the metal accumulation by plants in most cases were decreased under the influence of reclamation measures. Moreover, the content of photosynthetic pigments and the assimilation of carbon dioxide increased in plants from the reclaimed site, which indicates the activation of the photosynthetic function, which plays a significant role in the adaptation of the orchid to the adverse conditions of the disturbed habitat. © 2021 Author(s).