Identification of pollution sources and spatial distribution of trace metals in soils of the industrial area El Hadjar (Annaba, Algeria)

ABSTRACT

The purpose of this study is to investigate trace metal contents in soils, to determine their spatial distribution, and to identify their potential natural either anthropogenic sources using multivariate statistical approaches. Soils were taken in the industrial area of El Hadjar (NE-Algeria) at 0-10 and 10-20 cm. The results revealed an order of Fe > Zn > Pb > Cu > Cr, whatever the depth. Mean concentrations of Fe, Zn, Pb, Cu and Cr were 31191, 219.87, 96.76, 47.87, 28.27 µg/g, respectively, at 0-10 cm, and 29,792, 304.09, 115.45, 49.08, 28.16 µg/g, at 10-20 cm. Cr and Fe mean concentrations were below or close to soils worldwide backgrounds. These metals perhaps principally derive from natural sources. The percentages of sites with Zn, Pb and Cu contents over the background values were: 88.23% (Zn) > 82.35% (Pb) > 52.94% (Cu) at 0-10 cm, and 94.11% (Zn) > 88.23% (Pb) > 41.17% (Cu) at 10-20 cm. Hotspot areas of metal contamination were mainly concentrated around the Arcelor Mittal complex which seems to be the strongest effect factor influencing the spatial distributions of these metals. Results of this study suggest that Cr and Fe are predominantly derived from natural sources; Pb and Zn from industrial sources; and Cu from agricultural and industrial ones.

KEYWORDS:

• Industrial area
• trace metals
• soil survey
• multivariate statistics
• enrichment factor
• spatial distribution

Acknowledgments

The authors express their sincere gratitude to the members of the Scientific and Technical Research Center on Arid Regions-CRSTRA (Biskra, Algeria) for providing the facilities for trace metal analysis, and Dr Gana Mohamed from Constantine 1 university for his help.

Data availability statement

The datasets used and/or analysed during the current study are available from the corresponding author on reasonable request. All data generated or analysed during this study are included in this published article.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Competing interests

The authors declare that they have no competing interests.

Additional information

Notes on contributors

Amira Taiba

Amira Taiba, Collected and prepared samples for analysis, performed analysis (trace metals extraction and soil physic-chemical characterisation), wrote paper.

Aboubakre Seddik Sahraoui

Aboubakre Seddik Sahraoui, Collected and prepared samples for analysis, performed analysis (trace metals extraction and soil physic-chemical characterisation).

Mohamed El Hadef El Okki

Mohamed El Hadef El Okki, Statistical analysis, wrote paper.

Leila Sahli

Leila Sahli, Trace metals measurements, data analysis, wrote the paper.