TITLE:
Heavy Metal Levels and Potential Ecological Risks Assessed at an Agroecosystem Site in Tropical Region
AUTHORS:
Luc Kalendele Lundemi, Stéphanie Salumu Neema, Emmanuel Kazinguvu Atibu, Crispin Kyela Mulaji, Thierry Tabou Tangou, Camille Ipey Nsimanda, Robert Bueya Suami, Marie Onokoko Esako, Dieudonné Eyul’Anki Musibono, Fernando Piedade Carvalho
KEYWORDS:
Agroecosystem Site, Heavy Metals, Soil, Sediment, Ecological Risk, Clarias gariepisnis, Pontoscolex corethrurus
JOURNAL NAME:
Journal of Geoscience and Environment Protection,
Vol.10 No.9,
September
14,
2022
ABSTRACT: The
concentrations and distribution of thirteen metals and metalloids were
investigated in soils, sediments, and two biological matrices (the fish Clarias gariepisnis and the earthworm Pontoscolex corethrurus) from the CECOMAF agroecosystem, in
Kinshasa, Democratic Republic of the Congo, in order to assess the impact of
anthropogenic activities. The results revealed high concentrations of heavy
metals, such as Cu, Zn, As, Cd, Pb, and Hg all above values recommended by
sediment quality guidelines and their probable effect levels on biota.
According to the calculated Enrichment Factor, soil and sediments ranked from
moderately to heavily polluted by Cu, Zn, Cd, Pb and Hg. The Contamination
Degree and other ecological risk indices indicated very high contamination and
very high ecological risks posed by Cd and Hg, respectively. The
Geoaccumulation Index indicated that current metal concentrations in the
agroecosystem originated from anthropogenic activities, while the Spearman
correlation matrix values indicated that Hg could originate from different
sources and pathways than the other metals. It was concluded that metals from
unchecked anthropogenic activities have negatively impacted agricultural
activities and fish production at the CECOMAF agroecosystem. Action to reduce
the contamination level and the ecological risks by remediating and preventing
metal pollution in the CECOMAF agroecosystem site is recommended.