Heavy metal concentrations in floodplain soils of the Innerste River and in leaves of wild blackberries (Rubus fruticosus L. agg.) growing within and outside the floodplain: the legacy of historical mining activities in the Harz Mountains (Germany)

AbstractWe studied heavy metal levels in floodplain soils of the Innerste River in northern Germany and in the leaves of wild blackberries (Rubus fruticosus L. agg.) growing within and in adjacent areas outside the river floodplain. Heavy metal contamination of the Innerste floodplain is a legacy of historical metal ore mining, processing, and smelting in the Harz Mountains. The heavy metal (Cd, Pb, Zn, Cu, Ni, and Cr) contents of previously studied soil samples from eleven floodplain sites along the Innerste River were re-analyzed statistically, and the levels of these metals in blackberry leaves were determined at five sites. Mean concentrations in the floodplain soils were elevated by factors of 4.59 to 28.5 for Cd, 13.03 to 158.21 for Pb, 5.66 to 45.83 for Zn, and 1.1–14.81 for Cu relative to the precautionary limits for soils stipulated by the German Federal Soil Protection and Contaminated Sites Ordinance. Cadmium, Pb, Zn, Cu, and Ni levels in floodplain soils decreased markedly downstream, as did the concentrations of Cd, Zn, and Ni in the leaves of blackberries from within the floodplain. Levels of Cd, Pb, and Zn in leaves of blackberries from within the floodplain significantly exceeded those of specimens from outside the floodplain. The findings of our study highlight the potential of wild blackberry as a biomonitor of soil pollution by Cd, Pb, and Zn and corroborate the massive heavy metal contamination of floodplain soils along the Innerste River observed in previous studies.

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Assessment of heavy-metal contamination of floodplain soils due to mining and mineral processing in the Harz Mountains, Germany

Environmental Geology ◽

10.1007/s002540050493 ◽

2000 ◽

Vol 39 (7) ◽

pp. 774-782 ◽

Cited By ~ 20

Author(s):

H.-E. Gäbler ◽

J. Schneider

Keyword(s):

Heavy Metal ◽

Metal Contamination ◽

Heavy Metal Contamination ◽

Mineral Processing ◽

Harz Mountains ◽

Floodplain Soils

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Sensitivity of Earthworm (Eisenia fetida) in Mining Soil from Ijero-Ekiti, Nigeria

Journal of Applied Sciences and Environmental Management ◽

10.4314/jasem.v25i4.19 ◽

2021 ◽

Vol 25 (4) ◽

pp. 609-613

Author(s):

S.O. Agbo ◽

M.A. Mustapha ◽

C.E. Ogaugwu ◽

O.G. Sodipe ◽

E.C. Chukwu ◽

...

Keyword(s):

Heavy Metal ◽

Rural Communities ◽

Metal Contamination ◽

Eisenia Fetida ◽

Heavy Metal Contamination ◽

Absorption Spectrometry ◽

Mining Site ◽

Mining Soil ◽

Reference Soil ◽

Metal Levels

Excavation and processing of mineral deposits are valuable revenue sources yet they contribute serious environmental problems worldwide. Mining activities are widespread and contribute to heavy metal contamination in rural communities in Ekiti State, Nigeria. Available research failed to establish how mining soil may impact on resident terrestrial organisms. This study assessed the health of soil from active mining site by testing it on earthworms (Eisenia fetida) for 10 weeks. Survival, mobility, morphology and behaviour of worms were assessed while soil was analyzed for selected heavy metals by atomic absorption spectrometry. Worm survival was evident as the proportion of reference soil increased in exposure mixture and improved until 92% in the control. Worms curled up at the bottom of test vessels with varying proportions of mining site soil and appeared discolored and dehydrated when taken out of test soil, with characteristic sluggishness, particularly as the proportion of mining soil increased in exposure mixtures. Though metal levels were within permissible limits, morphology of exposed worms were visibly impacted, which corresponds in severity with increasing proportion of mining soil. On the contrary, worms tested in 100% reference soil appeared healthy and active in upper part of exposure vessels. These results suggest that the tested mining soil had adverse impacts on mobility, morphology, behavior and survival of exposed organisms when compared with the control population. Therefore, food products grown downstream of the mining site may be at risk of heavy metal contamination with consequences on food quality, water quality and food chain.

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Structure of Sediment-Associated Microbial Communities along a Heavy-Metal Contamination Gradient in the Marine Environment

Applied and Environmental Microbiology ◽

10.1128/aem.71.2.679-690.2005 ◽

2005 ◽

Vol 71 (2) ◽

pp. 679-690 ◽

Cited By ~ 136

Author(s):

David C. Gillan ◽

Bruno Danis ◽

Philippe Pernet ◽

Guillemette Joly ◽

Philippe Dubois

Keyword(s):

Heavy Metal ◽

Marine Environment ◽

Marine Sediments ◽

Metal Contamination ◽

Heavy Metal Contamination ◽

Dry Weight ◽

Contaminated Site ◽

Wide Range ◽

Metal Levels ◽

Extractable Metals

ABSTRACT Microbial community composition and structure were characterized in marine sediments contaminated for >80 years with cadmium, copper, lead, and zinc. Four sampling sites that encompass a wide range of sediment metal loads were compared in a Norwegian fjord (Sørfjord). HCl-extractable metals and organic matter constantly decreased from the most contaminated site (S1) to the control site (S4). All sampling sites presented low polychlorinated biphenyl (PCB) concentrations (Σ7PCB < 7.0 ng g [dry weight]−1). The biomass ranged from 4.3 × 108 to 13.4 × 108 cells g (dry weight) of sediments−1 and was not correlated to metal levels. Denaturing gradient gel electrophoresis indicated that diversity was not affected by the contamination. The majority of the partial 16S rRNA sequences obtained were classified in the γ- and δ-Proteobacteria and in the Cytophaga-Flexibacter-Bacteroides (CFB) bacteria. Some sequences were closely related to other sequences from polluted marine sediments. The abundances of seven phylogenetic groups were determined by using fluorescent in situ hybridization (FISH). FISH was impaired in S1 by high levels of autofluorescing particles. For S2 to S4, the results indicated that the HCl-extractable Cu, Pb, and Zn were negatively correlated with the abundance of γ-Proteobacteria and CFB bacteria. δ-Proteobacteria were not correlated with HCl-extractable metals. Bacteria of the Desulfosarcina-Desulfococcus group were detected in every site and represented 6 to 14% of the DAPI (4′,6′-diamidino-2-phenylindole) counts. Although factors other than metals may explain the distribution observed, the information presented here may be useful in predicting long-term effects of heavy-metal contamination in the marine environment.

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Ancient Heavy Metal Contamination in Soils as a Driver of Tolerant Anthyllis vulneraria Rhizobial Communities

Applied and Environmental Microbiology ◽

10.1128/aem.01735-16 ◽

2016 ◽

Vol 83 (2) ◽

Cited By ~ 8

Author(s):

Roba Mohamad ◽

Geraldine Maynaud ◽

Antoine Le Quéré ◽

Céline Vidal ◽

Agnieszka Klonowska ◽

...

Keyword(s):

Heavy Metal ◽

Metal Contamination ◽

Heavy Metal Contamination ◽

Metal Tolerance ◽

Taxonomic Composition ◽

Soil Conditions ◽

Site Specific ◽

Content Type ◽

Anthyllis Vulneraria ◽

Metal Levels

ABSTRACT Anthyllis vulneraria is a legume associated with nitrogen-fixing rhizobia that together offer an adapted biological material for mine-soil phytostabilization by limiting metal pollution. To find rhizobia associated with Anthyllis at a given site, we evaluated the genetic and phenotypic properties of a collection of 137 rhizobia recovered from soils presenting contrasting metal levels. Zn-Pb mine soils largely contained metal-tolerant rhizobia belonging to Mesorhizobium metallidurans or to another sister metal-tolerant species. All of the metal-tolerant isolates harbored the cadA marker gene (encoding a metal-efflux PIB-type ATPase transporter). In contrast, metal-sensitive strains were taxonomically distinct from metal-tolerant populations and consisted of new Mesorhizobium genospecies. Based on the symbiotic nodA marker, the populations comprise two symbiovar assemblages (potentially related to Anthyllis or Lotus host preferences) according to soil geographic locations but independently of metal content. Multivariate analysis showed that soil Pb and Cd concentrations differentially impacted the rhizobial communities and that a rhizobial community found in one geographically distant site was highly divergent from the others. In conclusion, heavy metal levels in soils drive the taxonomic composition of Anthyllis-associated rhizobial populations according to their metal-tolerance phenotype but not their symbiotic nodA diversity. In addition to heavy metals, local soil physicochemical and topoclimatic conditions also impact the rhizobial beta diversity. Mesorhizobium communities were locally adapted and site specific, and their use is recommended for the success of phytostabilization strategies based on Mesorhizobium-legume vegetation. IMPORTANCE Phytostabilization of toxic mine spoils limits heavy metal dispersion and environmental pollution by establishing a sustainable plant cover. This eco-friendly method is facilitated by the use of selected and adapted cover crop legumes living in symbiosis with rhizobia that can stimulate plant growth naturally through biological nitrogen fixation. We studied microsymbiont partners of a metal-tolerant legume, Anthyllis vulneraria, which is tolerant to very highly metal-polluted soils in mining and nonmining sites. Site-specific rhizobial communities were linked to taxonomic composition and metal tolerance capacity. The rhizobial species Mesorhizobium metallidurans was dominant in all Zn-Pb mines but one. It was not detected in unpolluted sites where other distinct Mesorhizobium species occur. Given the different soil conditions at the respective mining sites, including their heavy-metal contamination, revegetation strategies based on rhizobia adapting to local conditions are more likely to succeed over the long term compared to strategies based on introducing less-well-adapted strains.

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