Screening for Autochthonous Phytoextractors in a Heavy Metal Contaminated Coal Mining Area

Abstract

In order to protect public health and crops from soil heavy metal (HM) contamination at a coal mining area in Henan, central China, HM pollution investigation and screening of autochthonous HM phytoextractors were conducted. The concentrations of cadmium (Cd), lead (Pb), copper (Cu) and zinc (Zn) in surface soils exceeded the corresponding local background values and the China National Standard (CNS). The maximum potential ecological risk (RI) was 627.30, indicating very high ecological risk. The monomial risk of Cd contributed the most to the RI, varying from 85.48% to 96.48%. The plant community structure in the study area was simple, and was composed of 24 families, 37 genera and 40 species. B. pilosa, A. roxburghiana, A. argyi, A. hispidus were found to be the most dominant species at considerable risk sites. Based on the comprehensive analysis of Cd concentration, bioconcentration factor, translocation factor and adaptability factor, B. pilosa and A. argyi had potential for phytoextraction at considerable risk sites. A. roxburghiana had potential for Cd phytoextraction at moderately risk sites and A. hispidus seemed suitable for phytostabilization. The results could contribute to the phytoremediation of the similar sites.

Phytoremediation potential of plants growing spontaneously on abandoned coal mine wastes

“…. The content of Cd in this study ranged from 0.01 to 0.77 mg/kg in aerial parts and roots with greatest concentration in A. scoparia (0.77 mg/kg in aerial parts and 0.63 mg/kg in root) Li et al (2017). observed the highest mean concentration of Cd in A. scoparia(2.62 mg/kg in aerial parts and 0.46 mg/kg in root) colonized on the coal waste dumps in China.…”

“…. In this study, coal wastes contained about 35 mg/kg Pb which was less than some other coal mine areas in Poland (63 mg/kg) and China (91 mg/kg;Ciesielczuk et al 2014;Li et al 2017). In the present study, Capparis spinosa was the only plant that accumulated Pb about 7 mg/kg in shoot while it was less than 1 mg/kg for other species.…”

Tolerance of Tithonia diversifolia and Chromolaena odorata in heavy metal simulated-polluted soils and three selected dumpsites

“…Heavy metals, unlike organic contaminants, cannot be biodegraded. As a consequence, they accumulate in the environment [ 2 ]. In addition, HM from the environment also migrates toward and accumulates in the living organisms by the processes of bioaccumulation and biomagnifications through the trophic levels of the ecosystem [ 2 ].…”

“…Some Africa countries like Nigeria is rich with coal deposit especially in Enugu State. This coal is also one of the most important pillars of China’s economy [ 2 ].The coal mining activity produces a large amount of coal gangues, from which toxic substances could be released during the destruction of gangue mineral structure under the combined effects of water, microorganisms, vegetation, sunlight radiation and heat [ 3 ].…”

An Overview of Carbon Footprint of Coal Mining to Curtail Greenhouse Gas Emissions

“…Grasses, shrubs, and trees can be used as plant objects of reclamation [148]. In Li [149], it is proposed to use native representatives of soils as a plant object of reclamation, because, firstly, they are more viable, and secondly, alien plant species can seriously change the local ecosystem. In [150], the ability of Cannabis sativa L. to grow and restore the soils of abandoned coal mines in Pennsylvania was studied.…”