DOI: 10.5061/dryad.z34tmpgt4
title: Biochar mitigates microplastic-induced Destabilization of soil organic carbon via molecular Recalcitrance and microbial process regulation

description: Soil organic carbon (SOC) stability is critical to climate mitigation but
 faces growing threats from microplastic (MP) pollution. Biochar (BC), a
 carbon-negative soil amendment, enhances SOC persistence through chemical
 stabilization and microbial modulation. However, its efficacy under
 simultaneous MP contamination remains unclear. We conducted a 30-day
 greenhouse incubation experiment, adding polypropylene MPs (PP, 1%) and
 biochar (BC, 2%) to soil to explore shifts in SOC molecular structure and
 microbial communities. While the addition of PP alone maintained bulk SOC
 content, it masked underlying destabilization by reducing aromatic carbon
 in humin (HM) and fulvic acid (FA). This process also enriched bacteria
 that degrade aromatic carbon, along with fermentative bacteria, ultimately
 increasing SOC vulnerability to future mineralization. BC
 addition increased SOC through dual stabilization mechanisms: (1) directly
 contributing aromatic structures to HM (23% higher aromatic carbon) and
 (2) suppressing bacterial groups involved in aromatic carbon degradation.
 Crucially, BC’s effects persisted in soils with coexisting PP, maintaining
 SOC molecular stability and microbial functionality. These findings
 underscore the potential of microplastics to influence long-term
 carbon–climate feedbacks by reducing SOC stability and altering microbial
 dynamics, while also highlighting biochar’s dual role as a carbon sink and
 a mitigator of microplastic effects.
description: # Biochar mitigates microplastic-induced Destabilization of soil organic
 carbon via molecular Recalcitrance and microbial process regulation
 Dataset DOI:
 [10.5061/dryad.z34tmpgt4](https://doi.org/10.5061/dryad.z34tmpgt4) #
 Description of the Data and File Structure The raw data for **“Biochar
 Mitigates Microplastic-Induced Destabilization of Soil Organic Carbon via
 Molecular Recalcitrance and Microbial Process Regulation”** are organized
 as follows: --- ## File: `FT-ICR-MS_BC.xlsx` **Description:**\ FT-ICR MS
 data of fulvic acid (FA) fractions extracted from soils with **biochar
 (BC) addition**. The dataset includes peak information, assigned molecular
 formulas, derived indices, and compound classifications. **Variables:** *
 **Observed.m.z**: Experimentally measured mass-to-charge ratio (m/z). *
 **calc..m.z**: Theoretical mass-to-charge ratio calculated from the
 molecular formula (m/z). * **formula**: Assigned molecular formula of the
 detected compound (C, H, O, N, S). * **Observed.Intens**: Peak intensity
 detected by FT-ICR MS (arbitrary units). * **C, H, N, O, S**: Number of
 carbon, hydrogen, nitrogen, oxygen, and sulfur atoms. * **type**:
 Elemental group classification (CHO, CHON, CHOS, CHONS). * **type2**:
 Compound class annotation (lipids, proteins, lignin-like, carbohydrates,
 unsaturated hydrocarbons, condensed aromatics, tannins). * **H_C**:
 Hydrogen-to-carbon atomic ratio (dimensionless). * **O_C**:
 Oxygen-to-carbon atomic ratio (dimensionless). * **NOSC**: Nominal
 oxidation state of carbon (dimensionless). * **delG0 (ΔG°)**: Standard
 Gibbs free energy of oxidation (kJ mol⁻¹ e⁻¹). * **DBE**: Double bond
 equivalent, degree of unsaturation (dimensionless). * **AI_mod**: Modified
 aromaticity index (dimensionless). * **N_C**: Nitrogen-to-carbon atomic
 ratio (dimensionless). * **rel_abu**: Relative abundance, normalized to
 total peak intensity (fraction, 0–1). --- ## File: `FT-ICR-MS_BCPP.xlsx`
 **Description:**\ FT-ICR MS data of fulvic acid (FA) fractions extracted
 from soils with **combined biochar (BC) and polypropylene microplastic
 (PP) addition**. The dataset includes peak information, assigned molecular
 formulas, derived indices, and compound classifications. **Variables:** *
 **Observed.m.z**: Experimentally measured mass-to-charge ratio (m/z). *
 **calc..m.z**: Theoretical mass-to-charge ratio calculated from the
 molecular formula (m/z). * **formula**: Assigned molecular formula of the
 detected compound (C, H, O, N, S). * **Observed.Intens**: Peak intensity
 detected by FT-ICR MS (arbitrary units). * **C, H, N, O, S**: Number of
 carbon, hydrogen, nitrogen, oxygen, and sulfur atoms. * **type**:
 Elemental group classification (CHO, CHON, CHOS, CHONS). * **type2**:
 Compound class annotation (lipids, proteins, lignin-like, carbohydrates,
 unsaturated hydrocarbons, condensed aromatics, tannins). * **H_C**:
 Hydrogen-to-carbon atomic ratio (dimensionless). * **O_C**:
 Oxygen-to-carbon atomic ratio (dimensionless). * **NOSC**: Nominal
 oxidation state of carbon (dimensionless). * **delG0 (ΔG°)**: Standard
 Gibbs free energy of oxidation (kJ mol⁻¹ e⁻¹). * **DBE**: Double bond
 equivalent, degree of unsaturation (dimensionless). * **AI_mod**: Modified
 aromaticity index (dimensionless). * **N_C**: Nitrogen-to-carbon atomic
 ratio (dimensionless). * **rel_abu**: Relative abundance, normalized to
 total peak intensity (fraction, 0–1). --- ## File: `FT-ICR-MS_PP.xlsx`
 **Description:**\ FT-ICR MS data of fulvic acid (FA) fractions extracted
 from soils with **polypropylene microplastic (PP) addition**. The dataset
 includes peak information, assigned molecular formulas, derived indices,
 and compound classifications. **Variables:** * **Observed.m.z**:
 Experimentally measured mass-to-charge ratio (m/z). * **calc..m.z**:
 Theoretical mass-to-charge ratio calculated from the molecular formula
 (m/z). * **formula**: Assigned molecular formula of the detected compound
 (C, H, O, N, S). * **Observed.Intens**: Peak intensity detected by FT-ICR
 MS (arbitrary units). * **C, H, N, O, S**: Number of carbon, hydrogen,
 nitrogen, oxygen, and sulfur atoms. * **type**: Elemental group
 classification (CHO, CHON, CHOS, CHONS). * **type2**: Compound class
 annotation (lipids, proteins, lignin-like, carbohydrates, unsaturated
 hydrocarbons, condensed aromatics, tannins). * **H_C**: Hydrogen-to-carbon
 atomic ratio (dimensionless). * **O_C**: Oxygen-to-carbon atomic ratio
 (dimensionless). * **NOSC**: Nominal oxidation state of carbon
 (dimensionless). * **delG0 (ΔG°)**: Standard Gibbs free energy of
 oxidation (kJ mol⁻¹ e⁻¹). * **DBE**: Double bond equivalent, degree of
 unsaturation (dimensionless). * **AI_mod**: Modified aromaticity index
 (dimensionless). * **N_C**: Nitrogen-to-carbon atomic ratio
 (dimensionless). * **rel_abu**: Relative abundance, normalized to total
 peak intensity (fraction, 0–1). --- ## File: `FT-ICR-MS_CK.xlsx`
 **Description:**\ FT-ICR MS data of fulvic acid (FA) fractions extracted
 from **control soils** without biochar or polypropylene microplastic
 addition. The dataset includes peak information, assigned molecular
 formulas, derived indices, and compound classifications. **Variables:** *
 **Observed.m.z**: Experimentally measured mass-to-charge ratio (m/z). *
 **calc..m.z**: Theoretical mass-to-charge ratio calculated from the
 molecular formula (m/z). * **formula**: Assigned molecular formula of the
 detected compound (C, H, O, N, S). * **Observed.Intens**: Peak intensity
 detected by FT-ICR MS (arbitrary units). * **C, H, N, O, S**: Number of
 carbon, hydrogen, nitrogen, oxygen, and sulfur atoms. * **type**:
 Elemental group classification (CHO, CHON, CHOS, CHONS). * **type2**:
 Compound class annotation (lipids, proteins, lignin-like, carbohydrates,
 unsaturated hydrocarbons, condensed aromatics, tannins). * **H_C**:
 Hydrogen-to-carbon atomic ratio (dimensionless). * **O_C**:
 Oxygen-to-carbon atomic ratio (dimensionless). * **NOSC**: Nominal
 oxidation state of carbon (dimensionless). * **delG0 (ΔG°)**: Standard
 Gibbs free energy of oxidation (kJ mol⁻¹ e⁻¹). * **DBE**: Double bond
 equivalent, degree of unsaturation (dimensionless). * **AI_mod**: Modified
 aromaticity index (dimensionless). * **N_C**: Nitrogen-to-carbon atomic
 ratio (dimensionless). * **rel_abu**: Relative abundance, normalized to
 total peak intensity (fraction, 0–1). --- ## File: `Soil_properties.xlsx`
 **Description:**\ Measurements of **soil organic carbon (SOC)**,
 **dissolved organic carbon (DOC)**, and **soil pH** under four treatments:
 * **CK**: Control (no amendment) * **BC**: Biochar addition * **PP**:
 Plant residues addition * **BCPP**: Combined biochar and plant residues
 addition Each treatment includes **three replicates** (e.g., CK_1, CK_2,
 CK_3). **Variables:** * **Sample**: Sample ID, indicating treatment and
 replicate number. * **SOC (g kg⁻¹)**: Soil organic carbon concentration. *
 **DOC (mg kg⁻¹)**: Dissolved organic carbon concentration. * **pH**: Soil
 pH measured in a soil-water suspension.