Elements availability in soil fertilized with pelletized fly ash and biosolids.

Area of Science:

• Environmental Science
• Soil Science
• Agronomy

Background:

• Industrial residues, such as biosolids and fly ash, are increasingly explored as soil amendments.
• Understanding their impact on soil properties, nutrient cycling, and potential contaminant mobility is crucial for sustainable agriculture.

Purpose of the Study:

• To evaluate the effects of pelletized biosolids combined with municipal solid waste incineration fly ash (MFA) or biofuel fly ash (BFA) on soil nutrient and toxic element availability.
• To assess the influence of these amendments on plant growth and element uptake.

Main Methods:

• Plant pot experiments were conducted using soil amended with 2% pelletized biosolids mixed with either MFA or BFA.
• Soil and plant samples were analyzed for nutrient concentrations, potentially toxic elements, plant biomass, and element uptake.

Main Results:

• Plant growth did not directly correlate with available nutrient content in the amended soil.
• MFA application led to increased soil concentrations of phosphorus, arsenic (As), cadmium (Cd), and lead (Pb).
• MFA amendment resulted in higher plant accumulation of As and Cd, despite lower uptake of aluminum (Al) and barium (Ba), and increased overall plant biomass compared to BFA and unamended soil.

Conclusions:

• While MFA can enhance plant biomass, its application significantly increases soil and plant concentrations of potentially toxic elements.
• Careful management is required to ensure that element additions from industrial residue amendments do not exceed plant uptake, preventing detrimental increases in soil background concentrations.