Evaluation of plant growth on degraded mine soils amended with class F fly ash and animal manures

Abstract

The coal power generation, livestock production and coal mining industries are three of the largest roleplayers in South Africa’s economy and environment. These industries respectively produce huge volumes of fly ash, organic wastes and degraded land, resulting in both financial and ecological impacts. The need, therefore, exists to explore the recycling potential of fly ash, and combinations of fly ash with cattle and chicken manure. The aim of this study is to determine whether class F fly ash and combinations of class F fly ash with cattle and chicken manure can serve as alternative soil amendments to establish a more sustainable plant production system on degraded soils. Phytotron pot trials simulating the post-mining land capability class for pastures and fodder crop production, were planted with winter rye (Secale cereale), Japanese millet (Echinochloa frumentacea) and forage sorghum (Sorgum vulgare). Two soils, cover soil and acid mine drainage impacted soil (AMD), were amended with twelve treatment combinations at two different levels, optimum and 2X optimum. Treatments included combinations of agricultural lime, fertiliser, chicken manure, cattle manure, and class F fly ash.