Development of calcium-modified biochar for enhanced phytoremediation of human-induced salt pollutants (HISPs)

Chemosphere. 2024 May:355:141860. doi: 10.1016/j.chemosphere.2024.141860. Epub 2024 Mar 31.

Abstract

Soil salinization is a major environmental hazard that limits land availability. Human-induced salt pollutants (HISPs) are regularly presented in large quantities on the contaminated site (such as brine leakages and salt-water spills), causing a devastating shock with high salt stress to the ecosystem. For instance, Saskatchewan resulted in a 48% drop in wheat production and a 0.3% decline in provincial GDP. As the calcium-modified biochar can potentially ameliorate the negative effects of HISPs on plants and improve the plant, phytoremediation with calcium-modified biochar can have increased detoxification of hazardous pollutants from sites. Therefore, the objective of our study was to develop a biochar-assisted phytoremediation employing diverse approaches to calcium modification for the sustainable removal of HISPs. The co-pyrolyzed calcium biochar achieved a remarkable removal rate of 18.06%, reducing salinity from 9.44 to 7.81 dS/m. During a 90-day long-term phytoremediation, the overall reduction rate of calcium-modified biochar stimulated the germination and growth of Thinopyrum ponticum. The result of post-treatment further indicated that co-pyrolyzed biochar with Ca transferred salt into the plant compared to Ca-coated biochar, which only immobilized HISPs on its surface. These results offer two different treatment approaches for diverse situations involving HISPs contamination, addressing current in-situ spills and providing a calcium-related biochar technology for further research in desalination.

Keywords: Biochar; Brine; Calcium modification; Human-induced salt pollutants (HISPs); Phytoremediation.

MeSH terms

  • Biodegradation, Environmental
  • Calcium
  • Calcium, Dietary
  • Charcoal
  • Ecosystem
  • Environmental Pollutants*
  • Humans
  • Plants
  • Soil
  • Soil Pollutants*

Substances

  • Environmental Pollutants
  • Calcium
  • biochar
  • Soil Pollutants
  • Charcoal
  • Calcium, Dietary
  • Soil