Articles | Volume 12, issue 1
https://doi.org/10.5194/soil-12-689-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/soil-12-689-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Operational POM increases are over-interpreted as SOM stabilization:quantifying untransformed straw and biochar residues via magnetic separation
Yuhan Xia
Key Laboratory of Soil Resource Sustainable Utilization for Commodity Grain Bases of Jilin Province, College of Resource and Environmental Science, Jilin Agricultural University, Changchun 130118, China
Sen Dou
CORRESPONDING AUTHOR
Key Laboratory of Soil Resource Sustainable Utilization for Commodity Grain Bases of Jilin Province, College of Resource and Environmental Science, Jilin Agricultural University, Changchun 130118, China
Song Guan
CORRESPONDING AUTHOR
Key Laboratory of Soil Resource Sustainable Utilization for Commodity Grain Bases of Jilin Province, College of Resource and Environmental Science, Jilin Agricultural University, Changchun 130118, China
Dilimulati Yalihong
Key Laboratory of Soil Resource Sustainable Utilization for Commodity Grain Bases of Jilin Province, College of Resource and Environmental Science, Jilin Agricultural University, Changchun 130118, China
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Yifeng Zhang, Sen Dou, Batande Sinovuyo Ndzelu, Rui Ma, Dandan Zhang, Xiaowei Zhang, Shufen Ye, and Hongrui Wang
SOIL, 8, 605–619, https://doi.org/10.5194/soil-8-605-2022, https://doi.org/10.5194/soil-8-605-2022, 2022
Short summary
Short summary
How to effectively convert corn straw into humic substances and return them to the soil in a relatively stable form is a concerning topic. Through a 360 d field experiment under equal carbon (C) mass, we found that return of the fermented corn straw treated with Trichoderma reesei to the field is more valuable and conducive to increasing easily oxidizable organic C, humus C content, and carbon pool management index than the direct application of corn straw.
Cited articles
Abakumov, E. and Eskov, A.: Organic Matter Structural Composition of Vascular Epiphytic Suspended Soils of South Vietnam, App. Sci., 13, 4473, https://doi.org/10.3390/app13074473, 2023.
Angst, G., Mueller, K. E., Nierop, K. G. J., and Simpson, M. J.: Plant- or microbial-derived? A review on the molecular composition of stabilized soil organic matter, Soil Biol. Biochem., 156, 108189, https://doi.org/10.1016/j.soilbio.2021.108189, 2021.
Arumugam, T., Kinattinkara, S., Vellingiri, K., Arumugam, M., Rajamani, J., and Jayaseelan, A.: Assessment of agricultural soil quality in macro and micronutrient analysis of Kasargod, Kerala, India, using GIS techniques, J. Hazard. Mater. Advances, 19, 100846, https://doi.org/10.1016/j.hazadv.2025.100846, 2025.
Banach-Szott, M., Debska, B., and Rosa, E.: Effect of soil pollution with polycyclic aromatic hydrocarbons on the properties of humic acids, J. Soils Sediments, 14, 1169–1178, https://doi.org/10.1007/s11368-014-0873-9, 2014.
Baragaño, D., Alonso, J., Gallego, J. R., Lobo, M. C., and Gil-Díaz, M.: Magnetite nanoparticles for the remediation of soils co-contaminated with As and PAHs, Chem. Eng. J., 399, 125809, https://doi.org/10.1016/j.cej.2020.125809, 2020.
Bhattacharyya, R., Kundu, S., Srivastva, A. K., Gupta, H. S., Prakash, V., and Bhatt, J. C.: Long term fertilization effects on soil organic carbon pools in a sandy loam soil of the Indian sub-Himalayas, Plant Soil, 341, 109–124, https://doi.org/10.1007/s11104-010-0627-4, 2011.
Bornø, M. L., Müller-Stöver, D. S., and Liu, F.: Biochar properties and soil type drive the uptake of macro- and micronutrients in maize (Zea mays L.), J. Plant Nutr. Soil Sci., 182, 149–158, https://doi.org/10.1002/jpln.201800228, 2019.
Brown, K. H., Bach, E. M., Drijber, R. A., Hofmockel, K. S., Jeske, E. S., Sawyer, J. E., and Castellano, M. J.: A long-term nitrogen fertilizer gradient has little effect on soil organic matter in a high-intensity maize production system, Global Change Biol., 20, 1339–1350, https://doi.org/10.1111/gcb.12519, 2014.
Burgeon, V., Fouché, J., Garré, S., Dehkordi, R. H., Colinet, G., and Cornelis, J.-T.: Young and century-old biochars strongly affect nutrient cycling in a temperate agroecosystem, Agr. Ecosyst. Environ., 328, 107847, https://doi.org/10.1016/j.agee.2021.107847, 2022.
Cambardella, C. A. and Elliott, E. T.: Particulate Soil Organic-Matter Changes across a Grassland Cultivation Sequence, Soil Sci. Soc. Am. J., 56, 777–783, https://doi.org/10.2136/sssaj1992.03615995005600030017x, 1992.
Cao, L., Zhang, X., Xu, Y., Xiang, W., Wang, R., Ding, F., Hong, P., and Gao, B.: Straw and wood based biochar for CO2 capture: Adsorption performance and governing mechanisms, Separat. Purific. Technol., 287, 120592, https://doi.org/10.1016/j.seppur.2022.120592, 2022.
Castellano, M. J., Mueller, K. E., Olk, D. C., Sawyer, J. E., and Six, J.: Integrating plant litter quality, soil organic matter stabilization, and the carbon saturation concept, Global Change Biol., 21, 3200–3209, https://doi.org/10.1111/gcb.12982, 2015.
Chen, H.-L., Zhou, J.-M., and Xiao, B.-H.: Characterization of dissolved organic matter derived from rice straw at different stages of decay, J. Soils Sediments, 10, 915–922, https://doi.org/10.1007/s11368-010-0210-x, 2010.
Christensen, B. T.: Physical Fractionation of Soil and Organic Matter in Primary Particle Size and Density Separates, in: Soil Restoration, vol. 17, edited by: Lal, R. and Stewart, B. A., Springer, New York, NY, 1–90, https://doi.org/10.1007/978-1-4612-2930-8_1, 1992.
Connell, R. K., James, T. Y., and Blesh, J.: A legume-grass cover crop builds mineral-associated organic matter across variable agricultural soils, Soil Biol. Biochem., 203, 109726, https://doi.org/10.1016/j.soilbio.2025.109726, 2025.
Cotrufo, M. F. and Lavallee, J. M.: Soil organic matter formation, persistence, and functioning: A synthesis of current understanding to inform its conservation and regeneration, in: Advances in Agronomy, vol. 172, Elsevier, 1–66, https://doi.org/10.1016/bs.agron.2021.11.002, 2022.
Cotrufo, M. F., Wallenstein, M. D., Boot, C. M., Denef, K., and Paul, E.: The Microbial Efficiency-Matrix Stabilization (MEMS) framework integrates plant litter decomposition with soil organic matter stabilization: do labile plant inputs form stable soil organic matter?, Global Change Biol., 19, 988–995, https://doi.org/10.1111/gcb.12113, 2013.
Cotrufo, M. F., Soong, J. L., Horton, A. J., Campbell, E. E., Haddix, M. L., Wall, D. H., and Parton, W. J.: Formation of soil organic matter via biochemical and physical pathways of litter mass loss, Nat. Geosci., 8, 776–779, https://doi.org/10.1038/ngeo2520, 2015.
Cotrufo, M. F., Haddix, M. L., Kroeger, M. E., and Stewart, C. E.: The role of plant input physical-chemical properties, and microbial and soil chemical diversity on the formation of particulate and mineral-associated organic matter, Soil Biol. Biochem., 168, 108648, https://doi.org/10.1016/j.soilbio.2022.108648, 2022.
Dou, S. and Li, K.: Effect of Organic Matter Application on CP-MAS-13C-NMR Spectra of Humic Acids from a Brown Soil, in: Molecular Environmental Soil Science at the Interfaces in the Earth's Critical Zone, edited by: Xu, J. and Huang, P. M., Springer, Berlin, Heidelberg, 29–31, https://doi.org/10.1007/978-3-642-05297-2_9, 2010.
Dou, S., Shan, J., Song, X., Cao, R., Wu, M., Li, C., and Guan, S.: Are humic substances soil microbial residues or unique synthesized compounds? A perspective on their distinctiveness, Pedosphere, 30, 159–167, https://doi.org/10.1016/S1002-0160(20)60001-7, 2020.
Duan, L., Wang, Q., Li, J., Wang, F., Yang, H., Guo, B., and Hashimoto, Y.: Zero valent iron or Fe3O4-loaded biochar for remediation of Pb contaminated sandy soil: Sequential extraction, magnetic separation, XAFS and ryegrass growth, Environ. Pollut., 308, 119702, https://doi.org/10.1016/j.envpol.2022.119702, 2022.
Dungait, J. A. J., Hopkins, D. W., Gregory, A. S., and Whitmore, A. P.: Soil organic matter turnover is governed by accessibility not recalcitrance, Global Change Biol., 18, 1781–1796, https://doi.org/10.1111/j.1365-2486.2012.02665.x, 2012.
Feng, H., Han, X., Biswas, A., Zhang, M., Zhu, Y., Ji, Y., Lu, X., Chen, X., Yan, J., and Zou, W.: Long-term organic material application enhances black soil productivity by improving aggregate stability and dissolved organic matter dynamics, Field Crops Res., 328, 109946, https://doi.org/10.1016/j.fcr.2025.109946, 2025.
Guo, X., Viscarra Rossel, R. A., Wang, G., Xiao, L., Wang, M., Zhang, S., and Luo, Z.: Particulate and mineral-associated organic carbon turnover revealed by modelling their long-term dynamics, Soil Biol. Biochem., 173, 108780, https://doi.org/10.1016/j.soilbio.2022.108780, 2022.
He, W., Wang, H., Ye, W., Tian, Y., Hu, G., Lou, Y., Pan, H., Yang, Q., and Zhuge, Y.: Distinct stabilization characteristics of organic carbon in coastal salt-affected soils with different salinity under straw return management, Land Degrad. Dev., 33, 2246–2257, https://doi.org/10.1002/ldr.4276, 2022.
Hua, F., Bruijnzeel, L. A., Meli, P., Martin, P. A., Zhang, J., Nakagawa, S., Miao, X., Wang, W., McEvoy, C., Peña-Arancibia, J. L., Brancalion, P. H. S., Smith, P., Edwards, D. P., and Balmford, A.: The biodiversity and ecosystem service contributions and trade-offs of forest restoration approaches, Science, 376, 839–844, https://doi.org/10.1126/science.abl4649, 2022.
Janzen, H. H.: Beyond carbon sequestration: soil as conduit of solar energy, Eur. J. Soil Sci., 66, 19–32, https://doi.org/10.1111/ejss.12194, 2015.
Khaledi, S., Delbari, M., Galavi, H., Bagheri, H., and Chari, M. M.: Effects of biochar particle size, biochar application rate, and moisture content on thermal properties of an unsaturated sandy loam soil, Soil Till. Res., 226, 105579, https://doi.org/10.1016/j.still.2022.105579, 2023.
Kleber, M., Sollins, P., and Sutton, R.: A conceptual model of organo-mineral interactions in soils: self-assembly of organic molecular fragments into zonal structures on mineral surfaces, Biogeochemistry, 85, 9–24, https://doi.org/10.1007/s10533-007-9103-5, 2007.
Lavallee, J. M., Soong, J. L., and Cotrufo, M. F.: Conceptualizing soil organic matter into particulate and mineral-associated forms to address global change in the 21st century, Global Change Biol., 26, 261–273, https://doi.org/10.1111/gcb.14859, 2020.
Li, X., Li, R., Zhan, M., Hou, Q., Zhang, H., Wu, G., Ding, L., Lv, X., and Xu, Y.: Combined magnetic biochar and ryegrass enhanced the remediation effect of soils contaminated with multiple heavy metals, Environ. Int., 185, 108498, https://doi.org/10.1016/j.envint.2024.108498, 2024.
Liang, J., Crowther, T. W., Picard, N., Wiser, S., Zhou, M., Alberti, G., Schulze, E.-D., McGuire, A. D., Bozzato, F., Pretzsch, H., de-Miguel, S., Paquette, A., Hérault, B., Scherer-Lorenzen, M., Barrett, C. B., Glick, H. B., Hengeveld, G. M., Nabuurs, G.-J., Pfautsch, S., Viana, H., Vibrans, A. C., Ammer, C., Schall, P., Verbyla, D., Tchebakova, N., Fischer, M., Watson, J. V., Chen, H. Y. H., Lei, X., Schelhaas, M.-J., Lu, H., Gianelle, D., Parfenova, E. I., Salas, C., Lee, E., Lee, B., Kim, H. S., Bruelheide, H., Coomes, D. A., Piotto, D., Sunderland, T., Schmid, B., Gourlet-Fleury, S., Sonké, B., Tavani, R., Zhu, J., Brandl, S., Vayreda, J., Kitahara, F., Searle, E. B., Neldner, V. J., Ngugi, M. R., Baraloto, C., Frizzera, L., Bałazy, R., Oleksyn, J., Zawiła-Niedźwiecki, T., Bouriaud, O., Bussotti, F., Finér, L., Jaroszewicz, B., Jucker, T., Valladares, F., Jagodzinski, A. M., Peri, P. L., Gonmadje, C., Marthy, W., O'Brien, T., Martin, E. H., Marshall, A. R., Rovero, F., Bitariho, R., Niklaus, P. A., Alvarez-Loayza, P., Chamuya, N., Valencia, R., Mortier, F., Wortel, V., Engone-Obiang, N. L., Ferreira, L. V., Odeke, D. E., Vasquez, R. M., Lewis, S. L., and Reich, P. B.: Positive biodiversity-productivity relationship predominant in global forests, Science, 354, aaf8957, https://doi.org/10.1126/science.aaf8957, 2016.
Liu, J., Sun, P., Chen, Y., Guo, J., Liu, L., Zhao, X., Xin, J., and Liu, X.: The regulation pathways of biochar and microorganism in soil-plant system by multiple statistical methods: The forms of carbon participation in coastal wetlands, Chemosphere, 362, 142918, https://doi.org/10.1016/j.chemosphere.2024.142918, 2024.
Mitchell, E., Scheer, C., Rowlings, D., Conant, R. T., Cotrufo, M. F., and Grace, P.: Amount and incorporation of plant residue inputs modify residue stabilisation dynamics in soil organic matter fractions, Agr. Ecosyst. Environ., 256, 82–91, https://doi.org/10.1016/j.agee.2017.12.006, 2018.
Mohammed, I., Kodaolu, B., Zhang, T., Wang, Y., Audette, Y., and Longstaffe, J.: Analysis of Molecular Structure Changes in Humic Acids from Manure-Amended Soils over 17 Years Using Elemental Analysis and Solid-State 13C Nuclear Magnetic Resonance Spectroscopy, Soil Syst., 7, 76, https://doi.org/10.3390/soilsystems7030076, 2023.
Ndzelu, B. S., Dou, S., Zhang, X., Zhang, Y., Ma, R., and Liu, X.: Tillage effects on humus composition and humic acid structural characteristics in soil aggregate-size fractions, Soil Till. Res., 213, 105090, https://doi.org/10.1016/j.still.2021.105090, 2021.
Nelson, D. W. and Sommers, L. E.: Total Carbon, Organic Carbon, and Organic Matter, in: Agronomy Monographs, vol. 9, edited by: Page, A. L., Wiley, 539–579, https://doi.org/10.2134/agronmonogr9.2.2ed.c29, 1982.
Panda, S., Devi, N. J., Maiti, P., Chatterjee, A., Hazra, P., Singh, V. K., Parmar, P., and Meikap, B. C.: Development of a novel FeCl3-activated magnetic biochar for adsorptive removal of paracetamol and environmental impact analysis, Powder Technol., 470, 122021, https://doi.org/10.1016/j.powtec.2025.122021, 2026.
Powlson, D. S., Stirling, C. M., Jat, M. L., Gerard, B. G., Palm, C. A., Sanchez, P. A., and Cassman, K. G.: Limited potential of no-till agriculture for climate change mitigation, Nat. Clim. Change, 4, 678–683, https://doi.org/10.1038/nclimate2292, 2014.
Rana, P., Soni, V., Sharma, S., Poonia, K., Patial, S., Singh, P., Selvasembian, R., Chaudhary, V., Hussain, C. M., and Raizada, P.: Harnessing nitrogen doped magnetic biochar for efficient antibiotic adsorption and degradation, J. Indust. Eng. Chem., S1226086X25000371, https://doi.org/10.1016/j.jiec.2025.01.025, 2025.
Ren, Z., Zhang, H., Wang, Y., Lu, L., Ren, D., and Wang, J.: Multiple roles of dissolved organic matter released from decomposing rice straw at different times in organic pollutant photodegradation, J. Hazard. Mater., 401, 123434, https://doi.org/10.1016/j.jhazmat.2020.123434, 2021.
Rocci, K. S., Lavallee, J. M., Stewart, C. E., and Cotrufo, M. F.: Soil organic carbon response to global environmental change depends on its distribution between mineral-associated and particulate organic matter: A meta-analysis, Sci. Total Environ., 793, 148569, https://doi.org/10.1016/j.scitotenv.2021.148569, 2021.
Shi, H., Liu, G., An, X., Zhao, Y., Zheng, F., Li, H., Zhang, X. (J.), Pan, X., Wu, B., and Wang, X.: Tracing soil erosion with Fe3O4 magnetic powder: Principle and application, Int. Soil Water Conserv. Res., 12, 419–431, https://doi.org/10.1016/j.iswcr.2023.08.002, 2024.
Shi, R.-Y., Ni, N., Wang, R.-H., Nkoh, J. N., Pan, X.-Y., Dong, G., Xu, R.-K., Cui, X.-M., and Li, J.-Y.: Dissolved biochar fractions and solid biochar particles inhibit soil acidification induced by nitrification through different mechanisms, Sci. Total Environ., 874, 162464, https://doi.org/10.1016/j.scitotenv.2023.162464, 2023.
Slessarev, E. W., Chadwick, O. A., Sokol, N. W., Nuccio, E. E., and Pett-Ridge, J.: Rock weathering controls the potential for soil carbon storage at a continental scale, Biogeochemistry, 157, 1–13, https://doi.org/10.1007/s10533-021-00859-8, 2022.
Sokol, N. W., Whalen, E. D., Jilling, A., Kallenbach, C., Pett-Ridge, J., and Georgiou, K.: Global distribution, formation and fate of mineral-associated soil organic matter under a changing climate: A trait-based perspective, Funct. Ecol., 36, 1411–1429, https://doi.org/10.1111/1365-2435.14040, 2022.
Stewart, C. E., Follett, R. F., Wallace, J., and Pruessner, E. G.: Impact of Biosolids and Tillage on Soil Organic Matter Fractions: Implications of Carbon Saturation for Conservation Management in the Virginia Coastal Plain, Soil Sci. Soc. Am. J., 76, 1257–1267, https://doi.org/10.2136/sssaj2011.0165, 2012.
Van, F. Y., Jaromir, K. J., and Tin, L. C.: Environmental Performance and Techno-Economic Feasibility of Different Biochar Applications: An Overview, Chem. Eng. Trans., 83, 469–474, https://doi.org/10.3303/CET2183079, 2021.
Vendig, I., Guzman, A., De La Cerda, G., Esquivel, K., Mayer, A. C., Ponisio, L., and Bowles, T. M.: Quantifying direct yield benefits of soil carbon increases from cover cropping, Nat. Sustain., 6, 1125–1134, https://doi.org/10.1038/s41893-023-01131-7, 2023.
Von Lützow, M., Kögel-Knabner, I., Ekschmitt, K., Flessa, H., Guggenberger, G., Matzner, E., and Marschner, B.: SOM fractionation methods: Relevance to functional pools and to stabilization mechanisms, Soil Biol. Biochem., 39, 2183–2207, https://doi.org/10.1016/j.soilbio.2007.03.007, 2007.
Wang, F., Zhou, F., Zhang, L., Liu, W., Su, Y., Zhang, Y., Hong, S., Zhan, M., Xie, B., and Zhou, Y.: Mechanisms of manganese-modified biochar and white-rot fungi in enhancing compost humification: Boosting polyphenol pathway by lignocellulose degradation, Chem. Eng. J., 507, 160637, https://doi.org/10.1016/j.cej.2025.160637, 2025.
Witzgall, K., Vidal, A., Schubert, D. I., Höschen, C., Schweizer, S. A., Buegger, F., Pouteau, V., Chenu, C., and Mueller, C. W.: Particulate organic matter as a functional soil component for persistent soil organic carbon, Nat. Commun., 12, 4115, https://doi.org/10.1038/s41467-021-24192-8, 2021.
Wood, S. A., Sokol, N., Bell, C. W., Bradford, M. A., Naeem, S., Wallenstein, M. D., and Palm, C. A.: Opposing effects of different soil organic matter fractions on crop yields, Ecol. Appl., 26, 2072–2085, https://doi.org/10.1890/16-0024.1, 2016.
Xie, H., Li, J., Zhu, P., Peng, C., Wang, J., He, H., and Zhang, X.: Long-term manure amendments enhance neutral sugar accumulation in bulk soil and particulate organic matter in a Mollisol, Soil Biol. Biochem., 78, 45–53, https://doi.org/10.1016/j.soilbio.2014.07.009, 2014.
Xu, S., Chen, Z., Zhang, N., Li, Y., Xu, Y., and Ding, W.: Soil carbon quality determined the responses of respiration components to nitrogen fertilization and straw return, Soil Till. Res., 259, 107072, https://doi.org/10.1016/j.still.2026.107072, 2026.
Yin, J., Zhao, L., Xu, X., Li, D., Qiu, H., and Cao, X.: Evaluation of long-term carbon sequestration of biochar in soil with biogeochemical field model, Sci. Total Environ., 822, 153576, https://doi.org/10.1016/j.scitotenv.2022.153576, 2022.
Zhang, B., Jin, Y., Qi, J., Chen, H., Chen, G., and Tang, S.: Porous carbon materials based on Physalis alkekengi L. husk and its application for removal of malachite green, Environ. Technol. Innov., 21, 101343, https://doi.org/10.1016/j.eti.2020.101343, 2021.
Zhang, B., Li, R., Zheng, Y., Chen, S., Su, Y., Zhou, W., Sui, Q., and Liang, D.: Biochar Composite with Enhanced Performance Prepared Through Microbial Modification for Water Pollutant Removal, Int. J. Molecu. Sci., 25, 11732, https://doi.org/10.3390/ijms252111732, 2024.
Zhang, G., Ren, R., Yan, X., Zhu, Y., Zhang, H., and Yan, G.: The key role of magnetic iron-to-biochar mass ratios in the dissipation of oxytetracycline and its resistance genes in soils with and without biodegradable microplastics, J. Environ. Manage., 377, 124658, https://doi.org/10.1016/j.jenvman.2025.124658, 2025.
Zhou, J., Liu, Y., Han, Y., Jing, F., and Chen, J.: Bone-derived biochar and magnetic biochar for effective removal of fluoride in groundwater: Effects of synthesis method and coexisting chromium, Water Environ. Res., 91, 588–597, https://doi.org/10.1002/wer.1068, 2019.
Short summary
Following organic amendment application, increases in particulate organic carbon (POC) are often overinterpreted as evidence of organic matter stabilization or new stable soil organic matter (SOM) formation. In fact, they may merely reflect persistent untransformed exogenous organic residues, especially pronounced in the early experimental phase. This overestimation decreases gradually with incubation time in the straw treatment, but remains stable under biochar amendment.
Following organic amendment application, increases in particulate organic carbon (POC) are often...