title: Leaching of soils during laboratory incubations does not affect soil organic carbon mineralisation but solubilisation.
abstract: Laboratory soil incubations provide controlled conditions to investigate carbon and nutrient dynamics; however, they are not free of artefacts. As carbon and nitrogen cycles are tightly linked, we aimed at investigating whether the incubation-induced accumulation of mineral nitrogen (Nmin) biases soil organic carbon (SOC) mineralisation. For this, we selected two soils representative of the C:N ratio values found in European temperate forests, and applied two incubation systems: 'closed' beakers and 'open' microlysimeters. The latter allowed leaching the soil samples during the incubation. By the end of the 121-day experiment, the low C:N soil significantly accumulated more Nmin in beakers (5.12 g kg-1 OC) than in microlysimeters (3.00 g kg-1 OC) but there was not a significant difference in SOC mineralisation at any point of the experiment. On the other hand, Nmin did not accumulate in the high C:N soil but, by the end of the experiment, leaching had promoted 33.9% more SOC solubilisation than beakers. Therefore, we did not find evidence that incubation experiments introduce a bias on SOC mineralisation. This outcome strengthens results from soil incubation studies.
authors.affiliation: Soil Science and Biogeochemistry, Department of Geography, University of Zurich, Zurich, Switzerland.|Department of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland.
authors.forename: Beatriz
authors.identifier: http://orcid.org/0000-0002-2428-3119
authors.initials: B
authors.lastname: González-Domínguez
authors.affiliation: Soil Science and Biogeochemistry, Department of Geography, University of Zurich, Zurich, Switzerland.
authors.forename: Mirjam S
authors.initials: MS
authors.lastname: Studer
authors.affiliation: Forest Soils and Biogeochemistry, Swiss Federal Institute for Snow, Forest and Landscape Research WSL, Birmensdorf, Switzerland.
authors.forename: Frank
authors.initials: F
authors.lastname: Hagedorn
authors.affiliation: Department of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland.
authors.forename: Pascal A
authors.initials: PA
authors.lastname: Niklaus
authors.affiliation: Soil Science and Biogeochemistry, Department of Geography, University of Zurich, Zurich, Switzerland.
authors.forename: Samuel
authors.initials: S
authors.lastname: Abiven
mesh_terms: D002244:Carbon / Q000032:analysis* / Q000737:chemistry; D065928:Forests; D008903:Minerals / Q000032:analysis / Q000737:chemistry; D009584:Nitrogen / Q000032:analysis / Q000737:chemistry; D012987:Soil / Q000737:chemistry*
chemical_list: D008903:Minerals; D012987:Soil; D002244:Carbon; D009584:Nitrogen