Publications des scientifiques de l'IRD

Amir H., Bordez L., Cavaloc Y., Jourand Philippe, Ducousso M., Juillot Farid. (2022). Effects of ultramafic topsoil stockpiling during mine activities on its microbial diversity and other microbiological and physicochemical characteristics. Ecological Engineering, 177, 106563 [11 p.]. ISSN 0925-8574.

Titre du document
Effects of ultramafic topsoil stockpiling during mine activities on its microbial diversity and other microbiological and physicochemical characteristics
Année de publication
2022
Type de document
Article référencé dans le Web of Science WOS:000794072600001
Auteurs
Amir H., Bordez L., Cavaloc Y., Jourand Philippe, Ducousso M., Juillot Farid
Source
Ecological Engineering, 2022, 177, 106563 [11 p.] ISSN 0925-8574
Nowadays, ecological restoration is considered the best solution for the rehabilitation of mining-degraded areas, particularly when it concerns valuable ecosystems. This is the case in New Caledonia, a hot spot of biodiversity, with 82% of endemic plant species in ultramafic soils. The use of topsoil to restore mined areas is an important practice. However, topsoil stockpiling can reduce soil fertility. We studied the evolution of different properties of two topsoils stored in 10 m height piles on mined areas, in order to characterize possible degradations. The effects of storage duration, depth, and topsoil origin were analyzed, focusing mainly on bacterial and fungal diversity assessed after bar-coded pyrosequencing, and expressed by operational taxonomic units (OTU). Microbial activity (carbon dioxyde production), arbuscular mycorrhizal fungi (AMF) spore numbers, bulk density and different other physicochemical characteristics were also determined. The studied ultramafic soils were characterized by a relatively high microbial diversity with 45 bacterial phyla and 7 fungal phyla. Bacterial and fungal OTU numbers did not vary significantly after 12 months of storage, but the community structures of these groups were changed. AMF diversity was significantly reduced by the storage. Microbial activity, AMF spore numbers, soil organic carbon, total nitrogen, cation exchange capacity, and carbon to nitrogen ratio (C/N) decreased significantly starting from 3 to 9 months of topsoil storage. In contrast, soil bulk density and pH increased, and extractable concentrations of potentially toxic metals varied only slightly. All the changes induced by topsoil stockpiling in microbial population structure, AMF diversity, and other biotic and abiotic traits may negatively affect soil functions and create perturbations of the reconstructed ecosystems after revegetation. It is then necessary to reduce the storage of ultramafic topsoils as far as possible. In all cases, the stockpiling should not exceed six months before its use in ecosystem restoration. It is also recommended to reduce the height of the stockpiles, when possible, to 1 m or less to minimize the compaction and the anaerobiosis.
Plan de classement
Pédologie [068] ; Biotechnologies [084]
Description Géographique
NOUVELLE CALEDONIE
Localisation
Fonds IRD [F B010085115]
Identifiant IRD
fdi:010085115
Contact
  • Coordonnées :
    IST / IRD Ile-de-France
    32 avenue Henri Varagnat
    93140 Bondy Cedex
    France
    Horizon Pleins textes
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