The publication highlights of this week pertain to a number of issues related to enhanced rock weathering, nature-based CDR, marine biomineralisation and direct ocean capture.
Enhanced Rock Weathering Boosts Ecosystem Multifunctionality via Improving Microbial Networks Complexity in a Tropical Forest Plantation
Abstract
Afforestation is expected to contribute to mitigate global change by promoting carbon stocks and multiple ecosystem services. However, the success of plantations may be limited by the availability of soil nutrients. This is especially critical for plantations in tropical ecosystems which are known to be nutrient poor ecosystems. Enhanced rock weathering (ERW) represents a promising strategy for improving soil health and carbon sequestration in such ecosystems.
We added wollastonite skarn, a calcium silicate rock, to soils in a rubber plantation in Yunnan, China, as part of an ERW strategy aimed at promoting soil functioning and biodiversity. Statistical significance was determined using a linear mixed-effects model, with p-values indicating the level of significance.
The addition of wollastonite skarn significantly enhanced key ecosystem functions related to carbon, nitrogen, phosphorous, silicon, biodiversity, and pathogen control. However, it did not significantly affect soil enzyme activity. Some of these responses to the addition of wollastonite skarn may be associated with an increase in soil pH.
Microbial network complexity played a critical role in explaining the changes in ecosystem multifunctionality in response to ERW, through both direct and indirect pathways.
Wang, Z. et al. (2025) Enhanced Rock Weathering Boosts Ecosystem Multifunctionality via Improving Microbial Networks Complexity in a Tropical Forest Plantation. 373 (123477) Journal of Environmental Management.
Read the full paper here: Enhanced Rock Weathering Boosts Ecosystem Multifunctionality via Improving Microbial Networks Complexity in a Tropical Forest Plantation I Journal of Environmental Management.
How Effective and Efficient is the Generation of Nature-Based Carbon Removal Quantified According to the Regulation on Carbon Removal and Carbon Farming Certification? An Evaluation Based on the Example of a Hypothetical Agroforestry System in Baden-Wurttemberg
Abstract
Nature-based carbon removal (CR) could play a key role in achieving climate neutrality but it does face quantification challenges. This study evaluates the effectiveness and efficiency of CR quantification under the Carbon Removals and Carbon Farming (CRCF) Regulation, using Baden-Württemberg (Germany) as a case study. We designed a hypothetical agroforestry system for valuable timber production compliant with the CRCF requirements, modelling potential GHG emission reductions and the benefit-potential ratio (share of the CRCF-compliant net CR benefit within the total GHG emission mitigation potential). The results revealed a significant shortfall between the total GHG mitigation potential (350 kt CO2eq) and the actual net CR benefit (205 kt CO2eq), representing only 5 % of BW’s agricultural emissions. The benefit-potential ratio was at most 59 %, with abatement costs ranging from €59 to €153 t CO2eq-1. Conservative estimates to improve reliability further lowered the ratio to 24 %, pushing costs to €244 t CO2eq-1. While agroforestry does manifest regional CR generation potential, it is unlikely to contribute significantly to large-scale CR under the current CRCF framework, as both flaws within its quantification base and the inherent properties of nature-based CR limit its effectiveness. Although transferability is restricted by focusing on valuable timber production in BW, our results highlighted the need for harmonized emission factors, system boundary definitions (particularly indirect land use change), and a clear distinction between CR (e.g., from carbon sequestration in soils) and reduced soil emissions. We advocate balancing the use of agroforestry with more durable CR strategies and imposing caps on nature-based CR contributions to ensure robust climate action.
Geier, C. et al. (2025) How Effective and Efficient is the Generation of Nature-Based Carbon Removal Quantified According to the Regulation on Carbon Removal and Carbon Farming Certification? An Evaluation Based on the Example of a Hypothetical Agroforestry System in Baden-Wurttemberg. 20 (101201) Environmental Challenges.
Co-benefit of forestation on ozone air quality and carbon storage in South China
Abstract
Substantial forestation-induced greening has occurred over South China, affecting the terrestrial carbon storage and atmospheric chemistry. However, these effects have not been systematically quantified due to complex biosphere-atmosphere interactions. Here we integrate satellite observations, forestry statistics, and an improved atmospheric chemistry model to investigate the impacts of forestation on both carbon storage and ozone air quality. We find that forestation alleviates surface ozone via enhanced dry deposition and suppressed turbulence mixing, outweighing the effect of enhanced biogenic emissions. The 2005-2019 greening mitigated the growing season mean surface ozone by 1.4 ± 2.3 ppbv, alleviated vegetation exposure by 15%-41% (depending on ozone metrics) in forests over South China, and increased Chinese forest carbon storage by 1.8 (1.6-2.1) Pg C. Future forestation may enhance carbon storage by 4.3 (3.8-4.8) Pg C and mitigate surface ozone over South China by 1.4 ± 1.2 ppbv in 2050. Air quality management should consider such co-benefits as forestation becomes necessary for carbon neutrality.
Liu, Z. et al. (2025) Co-benefit of forestation on ozone air quality and carbon storage in South China. 16 (2429) Nature Communications.
Read the full paper here: Co-benefit of forestation on ozone air quality and carbon storage in South China I Nature Communications.
Harnessing the Biomolecular Mechanisms of Marine Biomineralisation for Carbon Sequestration
Abstract
Anthropogenic activities, primarily fossil fuel combustion, have increased atmospheric carbon dioxide (CO2) levels and climate change effects. Carbon dioxide removal (CDR) is now widely accepted as essential in all pathways to limit global warming in line with the Paris Agreement. Biomineralisation offers compelling and promising natural pathways for durable carbon sequestration by converting CO₂ into stable carbonate minerals, a process driven by a suite of biomolecules within bio-calcifying organisms. These processes are orchestrated by biomolecules such as proteins (e.g., carbonic anhydrase, urease, bicarbonate and calcium ion transporters, templating proteins) and polysaccharides, which regulate nucleation, crystal growth, and stabilisation within specialised microenvironments. This review provides an in-depth exploration of how diverse marine bio-calcifying organisms including corals, molluscs, foraminifera, and microbial mats leverage their unique biochemistry and physiology to regulate intra/extra cellular ion concentrations and pH, thereby enabling precise control over calcium carbonate (CaCO₃) precipitation. This review highlights the intricate molecular mechanisms that underpin natural carbon biomineralisation and examines how tools from engineering biology such as engineered enzymes, photosynthetic and ureolytic microbial consortia, and cell-free systems can be leveraged to mimic and amplify these processes for enhanced carbon capture. Bridging a deep understanding of natural calcification with advanced biotechnological tools has the potential to drive the innovation and development of powerful carbon removal technologies urgently needed to reach net zero and beyond.
Sanyal, S. et al. (2025) Harnessing the Biomolecular Mechanisms of Marine Biomineralisation for Carbon Sequestration. 83 (108644) Biotechnology Advances.
Read the full paper here: Harnessing the Biomolecular Mechanisms of Marine Biomineralisation for Carbon Sequestration I Biotechnology Advances.
Review on CO2 Removal from Ocean with an Emphasis on Direct Ocean Capture (DOC) Technologies
Abstract
Carbon dioxide (CO2) capture and removal are pivotal in addressing climate change. Beyond capturing CO2 directly from industrial emissions, the scope of greenhouse gas control has been extended to include technologies designed to remove CO2 from the atmosphere. Recent developments focus on maturing promising Carbon Dioxide Removal (CDR) technologies that remove and permanently store CO2. This article specifically examines a subset of CDR technologies referred to as ocean-based negative emission technologies (ONETs). The technologies under review involve modifications to seawater chemistry aimed at maximizing the ocean’s potential as a CO2 sink. Specifically, electrochemical ocean capture (EOC) and ocean alkalinity enhancement (OAE) are discussed.
There is a growing interest towards electrochemical ocean capture (EOC) utilizing different approaches, such as bipolar membrane electrodialysis (BPMED), three-chambered electrolytic cation exchange module (E-CEM), electrochemical hydrogen looping (EHL) and asymmetric chloride-mediated electrochemical process. The literature review shows that recent developments have up to 91% CO2 capture efficiency and a record-low electricity consumption in the electrodialysis process of 2.4 GJ/tonneCO2 with an EHL system and up to 87% CO2 capture efficiency with an electricity consumption of 2.8 GJ/tonneCO2 in the asymmetric chloride-mediated electrochemical process. Potential industrial and environmental challenges and solutions for the successful large-scale implementation of ONETs for greenhouse gas removal are discussed.
Karunarathne, S. et al. (2025) Review on CO2 Removal from Ocean with an Emphasis on Direct Ocean Capture (DOC) 353 Technologies. Separation and Purification Technology.
Read the full paper here: Review on CO2 Removal from Ocean with an Emphasis on Direct Ocean Capture (DOC) 353 Technologies. Separation and Purification Technology.