Schlagwort: enhanced weathering

Peer-reviewed Publications

Thompson et al. (2026): Integrated thermal and phytoremediation of agricultural soils impacted by PFAS

Jake T. Thompson, Millie Dobson, Tim Jesper Suhrhoff, et al., IN: Proceedings of the National Academy of Sciences (PNAS), https://doi.org/10.1073/pnas.2600786123

Per- and polyfluoroalkyl substances (PFAS) are persistent synthetic compounds that have contaminated millions of hectares of agricultural land through decades of biosolids application. Conventional remediation approaches, such as thermal destruction or excavation, are prohibitively expensive, carbon intensive, and leave affected farmland unfit for agriculture. Here, the authors present a potential scalable remediation strategy that combines phytoremediation, biochar production, and enhanced weathering to simultaneously remove PFAS from soil, immobilize residual contamination, and achieve durable carbon dioxide removal (CDR). Using stochastic modeling constrained by experimental data, they show that soil pH management through alkaline rock amendment can accelerate PFOS removal, shortening remediation timelines by more than a decade under typical contamination levels.

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Peer-reviewed Publications

Suhrhoff et al. (2026): An Ecosystem of Carbon Dioxide Removal Reviews – Part 3: Enhanced Weathering

Tim Jesper Suhrhoff, Christiana Dietzen, Tyler Kukla, Abby Lunstrum, Tom Reershemius et al., IN: CDR.Xiv (Preprint), https://doi.org/10.70212/cdrxiv.2026417.v1

Enhanced Weathering (EW) is an emerging Carbon Dioxide Removal (CDR) approach within a growing portfolio of mitigation strategies, offering the potential for durable CDR alongside agronomic co-benefits. As interest in CDR increases, EW is transitioning from a primarily scientific concept toward early-stage implementation, requiring a comprehensive synthesis of the current evidence base. This systematic review focuses primarily on soil-based EW using silicate rock feedstocks. Across empirical and modelling studies, area-normalized CDR fluxes have a median value of 0.84 tonnes of carbon dioxide per hectare per year (tCO₂ ha⁻¹ yr⁻¹) and span several orders of magnitude. The variance in reported fluxes reflects not only context-dependent differences in EW performance, but also the diversity of quantification approaches, which differ by use case and vary in terms of their system boundaries and treatment of loss processes. When scaled globally, evidence from empirical constraints and/or modelling approaches converges on a maximum technical CDR potential of ~0.2–2 GtCO₂ yr⁻¹, though some estimates are higher. Significant uncertainty remains regarding the magnitude, persistence, and timing of loss processes after initial CDR has occurred, including secondary phase formation and cation exchange, and in how these losses depend on local soil and climate conditions and deployment strategies. Interactions with soil organic carbon introduce additional uncertainty but also the potential for increasing total CDR. Beyond CDR, EW is consistently associated with improvements in soil properties and crop productivity. Its deployment within managed land systems creates opportunities for synergies with other land-based CDR approaches, enabling combined inorganic and biological carbon sequestration. At the same time, EW raises important socio-economic and governance considerations, including distributional impacts, environmental risks, and conditional public support.

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Peer-reviewed Publications

Vienne et al. (2026): River alkalinity enhancement for scalable and energy-efficient geochemical carbon dioxide removal: potential, costs and risks?

Arthur Vienne, Tom Cox, Harun Niron, Tim Jesper Suhrhoff and Sara Vicca, IN: CDR.Xiv (Preprint), https://doi.org/10.70212/cdrxiv.2026539.v1

Gigaton-scale carbon dioxide removal (CDR) from the atmosphere will be necessary to limit global warming to below 2 C. Current approaches, such as afforestation or biochar, are constrained by land and biomass availability, whereas direct-air carbon capture technologies are energy-intensive and costly. Here, the authors discuss river alkalinity enhancement (RAE), a geochemical carbon dioxide removal strategy that uses readily available limestone (CaCO₃) and derived slaked lime (Ca(OH)₂) to increase alkalinity in rivers. Unlike the direct addition of these minerals to the ocean, which is currently restricted by the London protocol, addition of alkalinity to rivers is already commercially applied in some regions and alkalinity dosing can be monitored in controlled systems. Controlled rock dissolution in ponds allows for direct measurement of CO₂ removal prior to water release back into rivers, enhancing traceability and verification.They simulate CO₂ uptake in 149 major rivers, considering river flows and chemistry and life-cycle emissions from mining, grinding and transporting rock and pumping water in reactor ponds.

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Peer-reviewed Publications

Jessen et al. (2026): Subsoil acidity causes long delays in inorganic carbon sequestration by Enhanced Weathering

Søren Jessen, Rasmus Jakobsen, Majken Looms, Per Ambus and Dieke Postma, IN: arXiv, https://doi.org/10.48550/arXiv.2607.01835

While a looming atmospheric CO₂ overshoot calls for immediate carbon sequestration, delays associated to Enhanced Weathering (EW) carbon dioxide removal are being investigated. Topsoil acidity is already known to delay EW carbon sequestration, but subsoil acidity remains underexplored. Using century-long agricultural liming of formerly acidic heathland as a proxy for EW, this study provides empirical evidence of subsoil-imposed delays.

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Peer-reviewed Publications

Lawrence et al. (2026): Evidence of microbially accelerated weathering from a laboratory mesocosm experiment with sequential selective dissolution

Corey R Lawrence, Harun Niron, Tania Timmermann, Philip D Weyman, Yun-Ya Yang, Daniel Dores and Gonzalo A Fuenzalida-Meriz, IN: CDRxiv, https://doi.org/10.70212/cdrxiv.2026464.v3

Microbially accelerated weathering (MAW) is a promising soil-based carbon dioxide removal (CDR) strategy that leverages beneficial soil microbes to increase weathering of preexisting silicate minerals. This approach does not require addition of a mineral feedstock, greatly reducing the carbon footprint from mining, grinding, transporting, and applying the mineral to land compared with enhanced weathering. A key obstacle to measurement, reporting, and verification for MAW is ensuring that increases in weathering products, such as base cations, are sourced from silicate dissolution rather than redistribution of pre-existing cations from the exchangeable, oxidizable, or reducible soil pools. To address this, the authors conducted a 63-day mesocosm study with soybean, utilizing soil sequential extractions to track the buildup and distribution of weathering products in soil columns inoculated with Bacillus subtilis strain MP1.

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Peer-reviewed Publications

Ali et al. (2026): Principal Current and Future Methods for Carbon Removal: Applications of Metal Oxides in Environmental Remediation

Farhad Ali, Asadullah Dawood, Muhammad Ramzan and Zeenat Jabeen, IN: Springer Nature, https://link.springer.com/rwe/10.1007/978-3-031-87501-4_9-1

Metal oxides have emerged as highly versatile and chemically tunable materials for addressing the global challenge of rising CO₂ emissions, which reached a record 37.8 Gt in 2024. This chapter reviews both established and emerging carbon dioxide removal (CDR) technologies, positioning metal oxides as central materials across multiple strategies including direct air capture, mineralization, enhanced weathering, and photocatalytic CO₂ reduction. The distinct chemical properties of alkaline earth oxides (CaO, MgO), transition metal oxides (TiO₂, Fe₂O₃, MnOₓ, CuO), and mixed metal oxide perovskites are examined in terms of their CO₂ adsorption mechanisms, redox activity, thermal stability, and bandgap tunability.

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Peer-reviewed Publications

Ansari et al. (2026): Rock-enhanced biochar exhibits similar priming effect as pure biochar application while improving short-term carbon stabilization in agricultural soils

Maria Ansari, Annemarie Lübeck, Johannes Meyer zu Drewer, Nikolas Hagemann, Annette Eschenbach and Joscha N. Becker, IN: Biology and Fertility of Soils, https://doi.org/10.1007/s00374-026-02030-7

Combined application of biochar and silicate rock powder might have synergistic effects on carbon dioxide removal and soil improvement. However, it remains unknown how their combination affects mineralization and stabilization of soil organic carbon (SOC). The authors compared pure 13C-labeled wheat-straw biochar, pure basanite rock powder, their co-application, and rock-enhanced biochar from co-pyrolysis of wheat and basanite. All amendments were mixed with three agricultural topsoils (temperate silty, temperate sandy, tropical sandy) and incubated for 66 days. The δ13C-signal of the respired CO₂ was monitored to determine amendment-induced priming of native SOC. After incubation, a density fractionation was conducted to investigate the potential stabilization of native and biochar-derived SOC as free particulate organic matter (fPOM), occluded POM (oPOM), and mineral-associated organic matter (MAOM).

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Peer-reviewed Publications

Zhang et al. (2026): Rock weathering can counteract river CO₂ emissions induced by permafrost thaw

Liwei Zhang, Aaron Bufe, Joshua F. Dean, Gerard Rocher-Ros, Ryan A. Sponseller, Emily H. Stanley, Jan Karlsson, David E. Butman, Ran Liu, Lijun Hou, Jinzhi Ding, Shilong Piao, Xinghui Xia and Tom J. Battin, IN: Nature, https://doi.org/10.1038/s41586-026-10664-8

Climate-induced permafrost thaw unlocks large stores of organic carbon that are mineralized and emitted as carbon dioxide (CO₂) from rivers to the atmosphere. Concurrently, warming and permafrost thaw can increase mineral weathering rates, thus affecting the release and sequestration of inorganic carbon. Yet how these biological and geological carbon cycles interact and jointly affect CO₂ dynamics (emission compared with drawdown) in permafrost rivers remains unknown. Here the authors combine CO₂ emissions, organic and inorganic solute concentrations, dual carbon isotopes (δ¹³C–Δ¹⁴C) and geochemical modelling to infer how permafrost thaw may affect river biogeochemistry over decades to centuries across the Qinghai–Tibet Plateau.

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Peer-reviewed Publications

Suhrhoff et al. (2026): Agricultural liming is a large carbon sink in the Mississippi River Basin – Preprint

Tim Jesper Suhrhoff, Christopher Reinhard, Yoshiki Kanzaki, Samuel Shou-En Tsao et al., IN: Research Square (Preprint), https://doi.org/10.21203/rs.3.rs-7068561/v1

The application of carbonate minerals to arable lands — agricultural liming — is a long-standing practice for counteracting soil acidification due to atmospheric pollution and anthropogenic fertilizer addition¹–³. While this practice boosts crop yields and mitigates soil acidification⁴, it is widely considered to be a significant component of agricultural emissions of carbon dioxide (CO₂)⁵. Here, the authors use a multi-decade timeseries of agricultural liming and anthropogenic acidity for the Mississippi River Basin — one of the largest agricultural catchments on Earth — together with results from reactive transport modeling to show that agricultural liming has acted as a net carbon sink over the last century.

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Peer-reviewed Publications

Cobo & Guillen Gosalbez (2026): Delayed climate benefits and toxicity risks could hinder the sustainable deployment of enhanced weathering

Selene Cobo and Gonzalo Guillen Gosalbez, IN: CDRXIV, https://doi.org/10.70212/cdrxiv.2026531.v1

Enhanced weathering has gained attention as a promising CO₂ removal (CDR) practice, but previous life cycle analyses rely on theoretical assumptions that differ substantially from experimental observations and overlook the risks of heavy metal emissions. Here, the authors draw on data from existing empirical studies to conduct a prospective life cycle assessment of multiple enhanced weathering scenarios.

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