In the urgent quest to mitigate climate change, carbon dioxide removal (CDR) strategies have emerged as vital tools for reducing atmospheric CO2 concentrations. A groundbreaking study published recently in Nature Communications by Moustakis, Wey, Nützel, and colleagues explores the synergistic effects of combining marine and terrestrial CDR methods. This innovative research challenges the conventional wisdom that co-applying different carbon sequestration techniques might diminish their individual efficacies. Instead, the authors provide compelling evidence that marine and terrestrial approaches can be jointly deployed without compromising their overall effectiveness, potentially revolutionizing climate intervention strategies.
The planet’s carbon cycle is complex, intertwined among oceans, forests, soil, and the atmosphere. Until now, most carbon removal efforts have focused on either terrestrial ecosystems, such as reforestation and soil carbon enhancement, or marine-based approaches like ocean fertilization and alkalinity enhancement. However, concerns have persisted that co-application of these methods might compete for resources, interfere chemically or biologically, or dilute each method’s impact. The new study rigorously tests these assumptions within a multidisciplinary framework, blending ecology, oceanography, and biogeochemistry, thereby providing a holistic view of CDR potential at the Earth system scale.
Central to the study is an integrated modeling system developed by the researchers, capable of simulating carbon dynamics across terrestrial and marine environments simultaneously. This model incorporates key biogeochemical feedbacks, carbon fluxes, and ecological responses, enabling precise predictions about how combined CDR methods interact over multiple decades. The authors employ this tool to investigate scenarios where enhanced terrestrial carbon uptake, achieved via afforestation and soil carbon amendments, coexists with marine strategies such as ocean alkalinity enhancement designed to increase seawater CO2 absorption.
One of the most striking findings is that terrestrial and marine carbon removal mechanisms operate largely independently in terms of their carbon capture efficiency. Terrestrial ecosystems primarily sequester carbon through biological processes like photosynthesis and soil carbon stabilization, while marine techniques manipulate chemical equilibria to augment oceanic CO2 storage capacity. Because these processes occur in distinct compartments of the Earth system, neither serves as a bottleneck to the other. This insight counters previously held fears that resource competition, such as nutrients or energy inputs, might limit the scalability of combined methods.
The study meticulously examines feedback loops within both systems. Terrestrial carbon sequestration is sensitive to climate-induced drought stress, fire regimes, and nutrient limitations, which can constrain long-term storage. Conversely, marine alkalinity enhancement alters seawater chemistry to reduce acidification while boosting CO2 uptake; yet it must be carefully managed to avoid unintended ecological consequences such as shifts in marine biodiversity or carbonate sediment dissolution. By cross-analysing these factors, Moustakis and colleagues demonstrate that carefully designed combined CDR strategies can mitigate individual weaknesses and enhance overall robustness.
Furthermore, the research highlights that simultaneous implementation could create complementary benefits beyond carbon removal alone. For example, increased terrestrial biomass can enhance soil moisture retention and reduce erosion, fostering ecosystem resilience amidst warming climates. Correspondingly, marine alkalinity enhancement helps safeguard coral reefs by counteracting ocean acidification, supporting fisheries vital for food security. These co-benefits underscore the multifaceted value of integrated marine-terrestrial CDR approaches, extending their appeal to policymakers and conservationists alike.
Critically, the authors also address economic and logistical considerations. The cost-efficiency of carbon removal is paramount to scalable deployment. Their model incorporates cost curves reflective of current technology readiness levels, infrastructure needs, and geographic constraints. Results indicate that co-application can leverage synergies in supply chains, monitoring systems, and governance frameworks, ultimately reducing the marginal cost per ton of CO2 removed. This finding suggests that rather than vying for limited funding, marine and terrestrial CDR initiatives could attract concerted investment channels, accelerating global decarbonization efforts.
Importantly, the paper advocates for iterative adaptive management informed by real-time monitoring. Since both marine and terrestrial ecosystems exhibit substantial spatial and temporal variability, continuous assessment is essential to optimize intervention parameters and detect unintended side effects early. The adoption of remote sensing, autonomous ocean sensors, and advanced soil carbon assays will be critical components in this endeavor. The authors emphasize that the success of co-applied CDR frameworks hinges not only on scientific understanding but also on robust governance, transparent data sharing, and collaboration among local communities, governments, and industry stakeholders.
From a technological perspective, the study explores recent advances in ocean alkalinity enhancement techniques, including electrochemical approaches that accelerate natural carbonate mineral dissolution. Paired with precision forestry methods and biochar soil amendments, these innovations represent the vanguard of scalable negative emissions technologies. The integration proposed by Moustakis and collaborators moves beyond isolated pilot projects by offering an evidence-based pathway toward global implementation, aligned with international climate targets such as the Paris Agreement’s aim of limiting warming to 1.5 degrees Celsius.
The paper also situates its findings within the broader context of Earth system modeling and climate policy. By demonstrating that combined marine-terrestrial carbon removal can achieve substantial net CO2 drawdown without sacrificing efficiency, it challenges mitigation scenarios that rely heavily on single approaches or geoengineering. The authors argue for a portfolio strategy, leveraging the strengths of diverse ecosystems and technological solutions to hedge against uncertainties inherent to future climate trajectories and ecosystem responses.
Critics have previously questioned the scalability and ecological safety of some CDR methods, especially ocean-based ones. This study addresses such skepticism by presenting a transparent assessment of environmental risks and recovery potentials, backed by extensive empirical datasets. While acknowledging remaining uncertainties, the researchers identify clear pathways to minimize harm and maximize benefits, thereby contributing crucial knowledge to the ongoing debate on responsible climate interventions.
Another compelling dimension discussed pertains to the sociopolitical implications. Implementing large-scale CDR interventions over terrestrial and marine realms requires multilevel coordination, encompassing local community engagement, national policy alignment, and international cooperation. The study’s integrative framework offers a scientific foundation to support policy dialogues, enabling stakeholders to evaluate trade-offs and co-develop equitable strategies that respect indigenous rights, promote biodiversity conservation, and create economic opportunities.
In concluding their work, Moustakis et al. call for an urgent expansion of interdisciplinary research efforts to refine CDR methodologies, enhance monitoring capabilities, and build inclusive governance infrastructures. They stress that time-sensitive action is critical, given the accelerating pace of climate change and the narrowing window for effective carbon management. Through their innovative approach, the authors illuminate a promising horizon where marine and terrestrial CDR efforts unify into a coherent, efficient toolkit to confront one of humanity’s greatest challenges.
This transformative study reverberates far beyond academic circles. By demonstrating that marine and terrestrial carbon dioxide removal strategies can be co-applied without compromising efficiency, it reshapes the paradigm for planetary stewardship. As governments and industries grapple with decarbonization imperatives, this breakthrough offers a scientifically robust, economically viable, and environmentally sound framework to amplify carbon sequestration at the scale demanded by the climate crisis. Its findings could well become a cornerstone of future climate policy and innovation, propelling us toward a more sustainable future.
Subject of Research: Combined application of marine and terrestrial carbon dioxide removal methods and their effect on carbon sequestration efficiency.
Article Title: No compromise in efficiency from the co-application of a marine and a terrestrial CDR method.
Article References:
Moustakis, Y., Wey, HW., Nützel, T. et al. No compromise in efficiency from the co-application of a marine and a terrestrial CDR method. Nat Commun 16, 4709 (2025). https://doi.org/10.1038/s41467-025-59982-x
Image Credits: AI Generated
