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Liu et al. (2025): Integrating experimental and geochemical modelling for productive carbon dioxide mineralization in the South China Sea

Bo Liu, Erfan Mohammadian, Amin Azdarpour, Rahim Masoudi, Chenlu Xu and Boyang Wang, IN: Communications Earth & Environment, https://doi.org/10.1038/s43247-025-02988-6

Reaching carbon neutrality requires innovative and scalable carbon sequestration technologies. Here, the authors present an enhanced ex-situ mineral carbonation method using South China Sea seawater and calcium-rich additives for carbon dioxide storage. The authors conducted high-pressure (50–500 atm) laboratory experiments using calcium oxide, calcium hydroxide, and wollastonite, and performed numerical geochemical simulations.

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Peer-reviewed Publications

Hammes et al. (2025): Soil processes govern alkalinity and cation retention in enhanced weathering for carbon dioxide removal

Jens S. Hammes, Jens Hartmann, Johannes A. C. Barth, Tobias Linke, Ingrid Smet, Mathilde Hagens, Philip A. E. Pogge von Strandmann, Tom Reershemius, Bruno Casimiro, Arthur Vienne, Anna A. Stoeckel, Ralf Steffens and Dirk Paessler, IN: EGUsphere, https://egusphere.copernicus.org/preprints/2025/egusphere-2025-5402/

Avoiding the most damaging consequences of climate change will almost certainly require pairing rapid emission cuts with large-scale carbon dioxide removal (CDR). Among the proposed CDR pathways, enhanced weathering (EW) accelerates natural mineral dissolution to convert atmospheric CO₂ into long-lived bicarbonate and carbonate reservoirs. Despite the many reported data from EW experiments, large uncertainty remains about the realisable CDR potential of applying rock materials to agricultural land. One of the relevant sinks for CO₂ is the transfer to bicarbonate alkalinity, and various EW studies have reported a wide range of results for this process. Intercomparison of these data is problematic due to the different experimental set-ups, environmental conditions as well as combinations of rock materials and soil types. In order to assess and compare the realisable CDR potential of various EW combinations, a large greenhouse experiment was set up in which 4 different soil types (7 different soil batches) were treated with 13 different feedstock materials.

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Peer-reviewed Publications

Suhrhoff et al. (2025): An Updated Framework and Signal-to-Noise Analysis of Soil Mass Balance Approaches for Quantifying Enhanced Weathering on Managed Lands

Tim Jesper Suhrhoff, Tom Reershemius, Jacob S. Jordan, Shihan Li, Shuang Zhang, Ella Milliken, Boriana Kalderon-Asael, Yael Ebert, Rufaro Nyateka, Jake T. Thompson, Christopher T. Reinhard and Noah J. Planavsky, IN: Environmental Science & Technology, https://doi.org/10.1021/acs.est.5c08303

Enhanced weathering is a promising approach for removing carbon dioxide from the atmosphere at scale while improving agricultural yields. However, accurately quantifying carbon dioxide removal in the field is critical for this approach to scale, particularly given that nearly all the current deployment activity caters to the voluntary carbon market. Here, the authors present an updated framework and a signal-to-noise analysis for using soil-based mass balance approaches to quantify rock powder dissolution from field-scale data of soil composition. With additional assumptions, the quantification of rock powder dissolution can be used to estimate the carbon dioxide removal potential of EW deployments.

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Peer-reviewed Publications

Hashim et al. (2025): Mineral formation during shipboard ocean alkalinity enhancement experiments in the North Atlantic

Mohammed S. Hashim, Lukas Marx, Frieder Klein, Chloe L. Dean, Emily Burdige, Matthew Hayden, Daniel C. McCorkle and Adam V. Subhas, IN: Biogeosciences, https://bg.copernicus.org/articles/22/7149/2025/bg-22-7149-2025.html

Ocean alkalinity enhancement (OAE) is a carbon dioxide (CO₂) removal approach that involves the addition of alkaline substances to the marine environment to increase seawater buffering capacity and allow it to absorb more atmospheric CO₂. Increasing seawater alkalinity leads to an increase in the saturation state (Ω) with respect to several minerals, which may trigger mineral precipitation, consuming the added alkalinity and thus decreasing the overall efficiency of OAE. To explore mineral formation due to alkalinity addition, the authors present results from shipboard experiments in which an aqueous solution of NaOH was added to unfiltered seawater collected from the surface ocean in the Sargasso Sea.

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Peer-reviewed Publications

Sovacool et al. (2025): Social attitudes towards climate interventions: Are European publics uninformed about carbon removal and solar radiation management?

Benjamin K. Sovacool, Livia Fritz, Chad M. Baum, Lucilla Losi, Ramit Debnath, Hans Jakob Walnum, Finn Müller-Hansen and Elina Brutschin, IN: Environmental Science & Policy, https://doi.org/10.1016/j.envsci.2025.104287

Climate interventions such as carbon removal and solar radiation management are now being considered by researchers, policymakers, and the private sector to address climate change. The authors examine European public perceptions of these interventions through five nationally representative surveys: Austria (N = 1005), Germany (N = 1025), Italy (N = 1002), Norway (N = 1002) and the United Kingdom (N = 1028). They combine this quantitative data with qualitative data from a total of 10 focus groups, with one urban and one rural focus group in each country.

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Peer-reviewed Publications

Gill et al. (2025): The Physiological Response of Contrasting Coccolithophore Species to Ocean Alkalinity Enhancement

Sophie Gill, Jiayou Ge, Qiong Zhang, Gideon M. Henderson, Rosalind E. M. Rickaby, IN: Journal of Geophysical Research: Biogeosciences, https://doi.org/10.1029/2025JG009103

Environmental impacts related to the Ocean Alkalinity Enhancement (OAE) on marine biota remain underexplored. Ocean Alkalinity Enhancement aims to increase the ocean’s total alkalinity (TA), shifting the carbonate buffer system to prompt air-sea gas exchange and CO₂ drawdown. These conditions might be favorable for calcifiers, leading to increased removal of alkalinity in CaCO₃ and reversing some of the intended benefit of the OAE. Here, the authors parameterize the impact of increased ocean alkalinity on two dominant end-member coccolithophore species: Gephyrocapsa huxleyi and Coccolithus braarudii.

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Peer-reviewed Publications

Tian et al. (2025): Stover return enhances the transformation and sequestration of photosynthetic carbon through regulating soil food web

Yijia Tian, Xinchang Kou, Tingting An, Liangjie Sun, Qi Li, Wenju Liang, Xiaoke Zhang, IN: Journal of Cleaner Production, https://doi.org/10.1016/j.jclepro.2025.146910

In agroecosystems, the biological fixation of atmospheric carbon by crops through photosynthesis is one of the most important precursors of soil carbon sequestration. Residue return as a conservational agricultural management practice replenishes soil carbon substrates and triggers soil food web. However, there is still a lack of studies on the priming effect of residue return on photosynthetic carbon transformation and turnover, and then soil carbon sequestration through regulating soil food web, which hinders us from evaluating the efficiency and sustainability of resource utilization. To analyze the priming effect of residue return, stover return (SR) and stover removal (CK) were conducted in the maize field experiment. Then the situ ¹³C labeling microplot experiment was further carried out to trace crop photosynthetic carbon turnover pathway into soil on the basis of the field experiment.

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Peer-reviewed Publications

Wang et al. (2025): Impact of Phase Change on Particle Migration in Carbon Dioxide Geological Storage

Tuo Wang, Xin Liang, Lihua Hu, Liyuan Liu, Chun’an Tang, Liyuan Yu, Qian Yin, Qinghe Niu, IN: Computers and Geotechnics, https://doi.org/10.1016/j.compgeo.2025.107780

As global warming intensifies, geological carbon storage (GCS) has emerged as a critical climate mitigation strategy, attracting widespread attention and becoming a key research area in engineering geology. The carbon dioxide (CO₂) migration within reservoirs has been examined, but the effects of phase change on reservoir behavior during CO₂ storage remain insufficiently characterized. In this study, the impact of phase change on particle migration in CO₂ storage was investigated through a resolved CFD-DEM-VOF method integrated with phase change model.

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Peer-reviewed Publications

Zhao et al. (2025): Achieving a carbon-negative region through carbon sinks and reduction initiatives: A case study of a coastal bay

Yating Zhao, Chang Tang, Jun Zhang, Hongtao Shen, Yahong Dong, IN: Journal of Environmental Management, https://doi.org/10.1016/j.jenvman.2025.127943

Regional carbon assessment is crucial for achieving carbon neutrality. However, challenges in data collection and the unverifiability of regional carbon emissions have led to a lack of verified assessments by recognized agencies. Most existing studies focused on carbon assessment of products, companies, or events, with little emphasis on verifying carbon emissions of regions, especially in coastal areas where significant economic activities occur, and large populations reside. This study attempts to conduct a regional carbon assessment for a coastal bay, Yanpu Bay, located in Zhejiang Province of China.

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Peer-reviewed Publications

Hailu et al. (2025): Evaluation of selected grass species for soil and water conservation, and carbon sequestration under farmland at Jimma Zone, southwestern Ethiopia

Leta Hailu, Gizaw Tesfaye, Wondimagegn Teka, Yalemstehay Debebe, Adugna Bayata, IN: Frontiers in Sustainable Food Systems, https://doi.org/10.3389/fsufs.2025.1552901

The objective of this study was to evaluate the effects of different grass species on soil and water conservation and carbon sequestration at a farmland in Jimma, Ethiopia. The experiment was set out as a randomized complete block design with three replications. The treatments were vetiver grass (Chrysopogon zizanioides L.), Desho grass (Pennisetum pedicellatum), Phalaris grass (Phalaris arundinacea L.) hedgerows, and the control (plots without grass). Soil erosion monitoring pins were installed, and the data were collected every 15 days. Soil samples were collected at 20 cm intervals in the top 100 cm before the grass hedgerows’ establishment and after harvesting seasons in December (2016–2019 G.C.). Fresh and oven-dry matter biomass (shoot and root) data were measured. The collected soil samples and grass biomass analysis for carbon fraction were determined following Black and Wakely (1934) and the loss on ignition standard procedure methods, respectively. Pin heights and soil moisture data were analyzed using R software.

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