Mineral acquisition by maize grown in acidic soil amended with coal combustion products

Large amounts of coal combustion products (CCPs) are produced when coal is burned for generation of electricity. Some of these CCPs could potentially be used as soil amendments, and information about their effects on plant mi neral nutrition is needed. Glasshouse experiments were conducted to test th e effects of different levels of 15 CCPs and chemical grade CaCO3, CaSO4, a nd CaSO3 added to acidic soil (Umbric Dystrochrept) on shoot calcium (Ca), sulfur (S), phosphorus (P), potassium (K), magnesium (Mg), manganese (Mn), iron (Fe), zinc (Zn), copper (Cu), and aluminum (Al) concentrations of maiz e (Zea mays L.). The CCPs consisted of two fly ashes (FAs), one CaO materia l, three fluidized bed combustion products (FBCs), three "non-stabilized" f lue gas desulfurization products (FGDs), three "stabilized" FGDs, and three "oxidized" (FGD gypsum) FGDs. Level of CCP added to soil ranged from benef icial to detrimental effects on plants. Differences in shoot mineral elemen t concentrations were related to kind and amount of CCP added and soil pH. Plants grown in unamended (pH 4) soil had symptoms of P and Mg deficiencies and A1 toxicity. High concentrations of Ca, S, Mg, and Mn accumulated when plants were grown with sonic CCPs, but most mineral nutrients were at conc entrations considered normal for maize. Shoot concentrations of P, K, Zn, M n, Fe, and A1 decreased when soil pH became high (>7). Even though detrimen tal mineral element acquisition effects were imposed on plants at high leve ls of CCP application, shoot element concentrations were usually normal whe n applied at levels near those commonly used as soil amendments.