Work

Interactive roles of mineralogy, microbial community composition and litter quality in regulating organic matter turnover

Year: 2026

Type: article

Abstract: Soils are often treated as chemically defined reactors, yet the physical architecture of minerals, organic inputs, and microbiomes jointly shapes where and how carbon turns over. We used a factorial microcosm experiment to test how clay mineralogy (fibrous palygorskite vs. swelling bentonite), clay content (0-20%), calcium carbonate (7.5-15%), litter quality (recalcitrant wheat vs. labile alfalfa), and microbiome origin (native soil vs. a synthetic fungi + bacteria consortium) interact to control respiration kinetics and microbial biomass carbon over 90 days. Clay type and amount acted as primary filters: increasing clay generally raised cumulative mineralized C, but palygorskite produced higher C₀, faster mineralization (higher k or lower t₀, steeper n), and stronger late-stage biomass recovery than bentonite, indicating a colonizable, catalytic habitat rather than a purely protective matrix. Litter chemistry modulated this filter: N-rich alfalfa shifted the system toward facilitation, with rapid, high-amplitude mineralization and large biomass peaks, whereas high-C:N wheat slowed mineralization, increased sensitivity to clay content, and emphasized protection and diffusion limitation. Microbiome composition added a third control: native communities generated higher cumulative C loss but lower rate constants, while the synthetic consortium drove faster mineralization and higher biomass on palygorskite. Calcium carbonate acted as a tuner, enhancing C₀, k and biomass in wheat systems and shifting mineralization timing in alfalfa systems. Together, these results support a hierarchical framework where mineral pore architecture sets the habitat filter, litter quality and microbial traits determine its exploitation, and Ca availability adjusts the balance between facilitation and protection.

Source: Scientific Reports

DOI: 10.1038/s41598-026-49740-4

Authors: Marziye Maqami, Banafshe Khalili, Hossein Shariatmadari

Institution: Isfahan University of Technology

Language: English

Topic: Soil Carbon and Nitrogen Dynamics

Subfield: Soil Science

Field: Agricultural and Biological Sciences

Domain: Life Sciences

SDGs: Life on land, Responsible consumption and production

Open Access status: gold

Estimated APC paid: $2,690