Growth performance and yield of rice grown in three different types of soil collected from rice fields with coal fly ash application

Coal fly ash (CFA) is a byproduct using coal as an energy source in power plants. The long-term storage of this industrial waste in open, indiscriminate disposal sites without further consumption poses environmental issues. Khan and Umar (2019) showed an increase in the concentration of several heavy metals in groundwater near CFA disposal sites, which exceeded the World Health Organisation’s (Dowhower et al. 2020) recommended drinking water standards. Several studies have also shown toxic contamination elements in soil and groundwater around the disposal sites (Kicińska 2019, Seki et al. 2021). The aforementioned results show the need for CFA management to prevent soil and groundwater exposure to toxic elements originating from leached CFA. The mineral and chemical properties of CFA allow the reuse of CFA to have a better economic value while simultaneously reducing environmental risks. CFA is used in manufacturing ceramic tiles and producing high-volume concretes (Luo et al. 2021). It also treats wastewater through adsorption, filtration, the Fenton process, photocatalysis, and coagulation (Mushtaq et al. 2019). Premkumar et al. (2017) reported that CFA is an effective stabiliser in enhancing the erosion resistance of dispersive soils. This industrial waste is also used in agriculture to improve soil properties and increase the yield of crops (Saidy et al. 2020, Haris et al. 2021, Ukwattage et al. 2021). The presence of oxides, which neutralise acidic soils, and trace elements, that provide nutrients for