A Report on
Biodiversity damage because of metal waste disposal
Environmental science
Submitted By
ATHARVA KAUSHIK
J040 G2 BATCH
SAP ID: 70092100092
Under The Guidance Of
Name of the Faculty Mentor
Prof. Sapna Shah
Mukesh Patel School of Technology & Management
Engineering
Department of Data Science
Vile Parle (w), Mumbai- 400056
Introduction:
One of the world's biggest environmental issues, metal contamination poses serious
risks to both ecosystems and the human population. Intense industrial activity and
insufficient waste disposal and treatment are the main causes of soil contamination.
For the purpose of evaluating metal pollution, it is also essential to have a solid
understanding of the quantity and variation of metals in soils related to both the
contribution of parent rock (lithogenic) and human activities (anthropogenic). It's
possible that 340,000 sites in Italy require immediate remediation. However,
traditional methods for cleaning up metal-contaminated soil have frequently been
pricy and disruptive.
Site-specific characterization should be the best strategy for preserving or restoring
the biodiversity of contaminated environments. The assessment of the biodiversity
of the surrounding area and the choice of tolerant organisms present on the polluted
sites are crucial for this purpose.
Bacteria in metal contaminated sites:
The stabilisation or active remediation of metal-contaminated ecosystems depends
on metalliferous biota, which is a significant research area in the modern field of
green technology. High selective pressure brought on by mine dumps makes it
possible for bacteria and microfungi to recolonize mine soils. In the detoxification
of harmful chemicals and in the regulation of plant growth, microfungal
communities are crucial players. As a means of survival in contaminated
environments, some arbuscular mycorrhizal fungi can compartmentalise copper in
their spores.
Case study 1:
The goal of the six-year multidisciplinary study summarised in this review was to
understand the connections between the mineralogy and chemistry of the Libiola
mine in eastern Liguria, Italy, and the metal uptake by fungi and plants that were
growing naturally in the mine waste dump. The mine is close to the Liguria sea
coast and is situated in a moderately steep mountainous terrain between 40 and 400
m asl.
One of Italy's most significant Fe-Cu sulphide mines is located in the Northern
Apennines. The Jurassic ophiolites of the Northern Apennine supergroup exhibit
sulphide mineralization. Five significant waste-rock dumps were gradually built up
during the course of exploitation using a variety of heterogeneous sterile rocks.
Because of their unusual physical and chemical characteristics, the soils in the
dumps are known for having severe edaphic conditions. One of the most
significant Fe-Cu sulphide mines in Italy, it produced over 1 Mt of Fe-Cu sulphides
during this time with an average grade ranging from 7 to 14 Cu wt%. The Jurassic
ophiolites of the Northern Apennines (Vara supergroup) contain sulphide
mineralization, which is characterised geologically by pillow basalts with minor
serpentinites, gabbros, and ophiolitic breccias.
The majority of the waste-rock materials deposited in the mining area are
gravely-sandy sediments with a comparatively uniform particle size distribution in
the 2-64 mm range. Strong superficial cementation caused by Fe-oxides
precipitating from acid sulphate water seepage is visible in most of the dumps.
When compared to the nearby serpentinitic and basaltic soils, the pH of
waste-dump soils is typically acidic and significantly lower. The majority of
recognised mineral species are serpentine minerals, which account for 60–70% of
all species, and Fe-oxyhydroxides, primarily goethite. The Libiola mine's waste
rock dumps are notable for having extremely high concentrations of potentially
toxic metals (like Ti, Mn, Co, Ni, V, Cr, Cu, Zn, and Cd). The majority of the
detected metals are also significantly higher than the Italian limits for residential
and commercial sites.
The regions close to the mine site are characterised by xero-acidophilous plant
communities. Despite challenging environmental conditions, Pinus pinaster Aiton
plants have gradually begun to colonise the waste-rock dump since 2008. It is well
known that maritime pine can adapt to some restrictions, such as a deficiency in
organic matter and macronutrients. P. pinaster serves as a phytostabilizer because it
can completely exclude harmful metals from its tissue.
To identify the microfungal flora, soil samples were taken from the A. utriculata
rhizosphere and barren mine soils. Aspergillus, Botrytis, Clonostachys,
Penicillium, and Trichoderma made up the majority of the isolated colonies overall
(Fig. 7). The ectomychorrizal macrofungi that were collected show highly
significant metal accumulation, especially in Telephora terrestris and Scleroderma
polyrhizum, which both contain Ag > 50000 mg kg-1. A high concentration of
silver, a noble metal with economic and historical significance, was also found in
the Libiola mine soil.
Even though silver is typically not regarded as an environmental contaminant, Ag+
is one of the metals that is most toxic to fish, bacteria, and algae. The fastest and
best-performing fungus to grow on media laced with 400 mg kg-1 of Ag+ was
Trichoderma sp.
Applications of the study:
Especially in regions that are characterised by a Mediterranean climate, the
complexity of the soil and the conditions that already exist at each contaminated
site necessitates the development of a decontamination plan that is unique to that
particular location. Multiple pollutants are present in multi-element contaminated
soils; as a result, it is necessary to screen out fungi and plants that can survive on
multiple pollutants at once and to accumulate or stabilise some of the pollutants.
Utilizing native species that have adapted to local conditions can help balance the
ecological pressure brought on by soil pollution. Therefore, before selecting other
species appropriate for bioremediation, it is necessary to assess the potential
bioremediation of native fungi and plants from contaminated sites. In the interim,
phytostabilization may be used in place of more advanced methods.
Reference:
Roccotiello, E., et al. “Biodiversity in Metal-Contaminated Sites – Problem and
Perspective – a Case Study | IntechOpen.” Biodiversity in Metal-Contaminated
Sites – Problem and Perspective – a Case Study | IntechOpen, 17 Apr. 2015,
www.intechopen.com/chapters/47841.