2026-04-17T03:41:41Zhttps://riubu.ubu.es/oai/request

oai:riubu.ubu.es:10259/111282025-12-13T01:05:26Zcom_10259_6168com_10259_5086com_10259_2604col_10259_6169

Campillo Cora, Claudia Soto Gómez, Diego Arias Estévez, Manuel Bååth, Erland Fernández Calviño, David 2025-12-12T09:45:03Z 2025-12-12T09:45:03Z 2021-11 0178-2762 https://hdl.handle.net/10259/11128 10.1007/s00374-021-01604-x 1432-0789 The PICT method (pollution-induced community tolerance) can be used to assess whether changes in soil microbial response are due to heavy metal toxicity or not. Microbial community tolerance baseline levels can, however, also change due to variations in soil physicochemical properties. Thirty soil samples (0–20 cm), with geochemical baseline concentrations (GBCs) of heavy metals and from five different parent materials (granite, limestone, schist, amphibolite, and serpentine), were used to estimate baseline levels of bacterial community tolerance to Cr, Ni, Pb, and Zn using the leucine incorporation method. General equations (n = 30) were determined by multiple linear regression using general soil properties and parent material as binary variables, explaining 38% of the variance in log IC50 (concentration that inhibits 50% of bacterial growth) values for Zn, with 36% for Pb, 44% for Cr, and 68% for Ni. The use of individual equations for each parent material increased the explained variance for all heavy metals, but the presence of a low number of samples (n = 6) lead to low robustness. Generally, clay content and dissolved organic C (DOC) were the main variables explaining bacterial community tolerance for the tested heavy metals. Our results suggest that these equations may permit applying the PICT method with Zn and Pb when there are no reference soils, while more data are needed before using this concept for Ni and Cr. Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. This study has been funded by the Spanish Ministry of Economy and Competitiveness through the project CTM2015-73422-JIN (FEDER Funds). David Fernández-Calviño holds a Ramón y Cajal contract (RYC-2016–20411) financed by the Spanish Ministry of Economy, Industry and Competitiveness. Claudia Campillo-Cora holds a predoctoral fellowship financed by Xunta de Galicia (ED481A-2020/084). Diego Soto-Gómez was supported by a postdoctoral fellowship from the Spanish Ministry of Education “Juan de la Cierva Formación (FJC2019-039176-I).” application/pdf eng Springer Biology and Fertility of Soils. 2021, V. 58, n. 1, p. 49-61 https://doi.org/10.1007/s00374-021-01604-x Atribución 4.0 Internacional http://creativecommons.org/licenses/by/4.0/ info:eu-repo/semantics/openAccess Bacterial growth Leucine incorporation Heavy metals Geochemical baseline level Co-tolerance Edafología Química agrícola Soil science Agricultural chemistry Estimation of baseline levels of bacterial community tolerance to Cr, Ni, Pb, and Zn in unpolluted soils, a background for PICT (pollution-induced community tolerance) determination info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion Biology and Fertility of Soils 58 1 49 61