Whispers in the mangroves: Unveiling the silent impact of potential toxic metals (PTMs) on Indian Sundarbans fungi

Mar Pollut Bull. 2024 Dec;209(Pt B):117233. doi: 10.1016/j.marpolbul.2024.117233. Epub 2024 Nov 21.

Abstract

This study investigates sediment samples from the Indian Sundarbans' mangrove habitat, where most samples were alkaline and hypersaline, except for one acidic sample. Elemental analysis revealed poor sediment quality, with elevated Enrichment Factors (2.20-9.7), Geo-accumulation indices (-2.19-1.19), Contamination Factors (0.61-3.18), and Pollution Load Indices (1.04-1.32). Toxic metal ions, including Pb, Cu, Ni, Cd, Zn, and Cr, were identified as key contributors to compromised sediment quality. These metals inhibit crucial sediment enzymes, such as CMC-cellulase, β-glucosidase, aryl sulfatase, urease, and phosphatases, essential for nutrient cycling and organic matter decomposition. A negative correlation was found between heavy metals and biodiversity, as indicated by the Shannon index, and a similar trend was observed with fungal load. The study highlights the adverse effects of persistent trace metals on the fungal community, potentially disrupting the mangrove ecosystem and suggests using manglicolous fungi as biological indicators of environmental health.

Keywords: Fungal diversity; Fungal metagenome; Indian Sundarbans; Mangrove; Potential toxic metals (PTMs); Sediment enzyme.

MeSH terms

  • Biodiversity
  • Environmental Monitoring*
  • Fungi*
  • Geologic Sediments / chemistry
  • India
  • Metals, Heavy* / analysis
  • Metals, Heavy* / toxicity
  • Water Pollutants, Chemical* / analysis
  • Water Pollutants, Chemical* / toxicity
  • Wetlands*

Substances

  • Metals, Heavy
  • Water Pollutants, Chemical