Search

Commercial investment in enhanced rock weathering for carbon dioxide removal on agricultural lands is growing rapidly. This Review explores the potential of large-scale deployment, outlining the challenges faced in science, policy and governance to scale the technology.

A state-level analysis of the impact of enhanced weathering deployment on carbon sequestration on agricultural land suggests that enhanced weathering could help the USA meet net-zero 2050 goals.

Symbiotic fungi are thought to have assisted plants in their colonization of the land. In this study, it is shown that mycorrhizal fungi symbiosis with liverwort, a member of an ancient clade of land plants, promotes photosynthetic carbon uptake and growth, supporting the role of fungi in 'the greening of the Earth'.

The mechanisms underlying drought-induced tree mortality are not fully resolved. Here, the authors show that, across multiple tree species, loss of xylem conductivity above 60% is associated with mortality, while carbon starvation is not universal.

A detailed assessment of the techno-economic potential of enhanced rock weathering on croplands identifies national CO₂ removal potentials, costs and engineering challenges if it were to be scaled up to help meet ambitious global CO₂ removal targets.

Theoretical analyses reveal how plant investment in the architecture of leaf veins can be shuffled for different conditions, minimizing the construction costs associated with supplying water to leaves.

Enhancing rock weathering across UK croplands could deliver substantial atmospheric carbon dioxide removal alongside agricultural co-benefits, according to coupled climate–carbon–nitrogen cycle model simulations.

Pulses of Saharan dust have been entering the North Atlantic since at least 11 Ma, a result of astronomically paced cycles between arid and humid conditions in northern Africa, according to a terrigenous input record from an ocean core off west Africa.

Global warming 55 million years ago was accompanied by a massive injection of carbon into the ocean-atmosphere system, but the resulting climatic warming was much greater than expected from the modelled rise in atmospheric carbon dioxide alone.

Carbon isotopes of fossil plants and model simulations suggest that atmospheric carbon dioxide levels were variable during the period 200 to 60 million years ago. The large decreases in the partial pressure of CO₂ coincide with glaciations, providing evidence against climate–CO₂ decoupling during the Mesozoic.

Vascular plants with root systems evolved in the mid-Palaeozoic with symbiotic fungi. Fieldet al. show that in contrast to non-vascular plants lacking roots, the efficiency of plant–fungal symbiosis increased for vascular plants with root systems as carbon dioxide levels declined in the mid-Palaeozoic.

Buried in a notebook from his undergraduate days lie Newton's musings on the movement of sap in trees. Viewed in conjunction with our modern understanding of plant hydrodynamics, his speculations seem prescient.

The ancient expansion of savannahs has long been examined through models and palaeorecords, but this new experiment combining CO₂ and drought finds the physiological mechanisms priming the forest-to-savannah transition.

Two genes controlling the transcriptional network involved in stomatal development in Arabidopsis thaliana have a conserved function in the non-vascular moss Physcomitrella patens. Moss mutants without stomata show delayed capsule dehiscence.

Destruction of the Earth’s ozone shield due to the release of hydrogen sulphide and methane has been suggested as a cause of mass extinctions during periods of ocean anoxia over the past two billion years. This mechanism does not explain the end-Permian mass extinction, according to simulations with a two-dimensional atmospheric chemistry-transport model, which show that the ozone shield remains intact even with massive releases of hydrogen sulphide and methane.

It is thought that the Earth's atmospheric carbon dioxide concentrations did not fall below about 200–250 parts per million during the past 24 million years despite the drawdown of atmospheric carbon dioxide by high rates of global silicate rock weathering. Simulations of terrestrial and geochemical carbon cycles now suggest that limited vegetation activity in regions of active mountain ranges effectively diminished biotic-driven silicate rock weathering and thereby provided a negative feedback mechanism to stabilize carbon dioxide concentrations.

Determining stratospheric ozone levels from before instrumental records began has proved difficult. Measurements of the chemical composition of plant spore walls suggest that ultraviolet-B-absorbing compounds have the potential to act as a proxy for past changes in ultraviolet-B radiation and stratospheric ozone.

The cause of the increase in atmospheric methane from 375 p.p.b.v. during the last ice age to 680 p.p.b.v. at the onset of Industrialization remains uncertain. Here, using an Earth system model, the authors show that we cannot reconcile this rise based on our current understanding of natural methane sources.

The chemical breakdown of rocks can be enhanced by spreading silicate granules over land. Research suggests that this measure, which increases the rate at which CO₂ is locked up in ocean carbonates, could lower atmospheric CO₂ by 30–300 ppm by 2100.

The One Thousand Plant Transcriptomes Initiative provides a robust phylogenomic framework for examining green plant evolution that comprises the transcriptomes and genomes of diverse species of green plants.

Reconstructions of atmospheric carbon dioxide concentrations over the past 65 million years are heading towards consensus. It is time for systematic testing of the proxies, against measurements and against each other.

Orbitally triggered decomposition of soil organic carbon in terrestrial permafrost is suggested as an explanation for a series of sudden and extreme global warming events that occurred about 55 million years ago.

The source of what seems to be an anomalous increase in atmospheric methane concentrations about 5,000 years ago compared to methane levels during previous interglacial periods has puzzled researchers. Possible explanations for the rise in methane levels include very early agricultural activity. Climate and wetland simulations of global methane levels over the last glacial cycle now suggest that the increase in methane concentrations can be explained by natural changes in the Earth's orbital configuration, with enhanced emissions in the Southern Hemisphere tropics linked to precession-induced modification of seasonal precipitation

Agriculture attempts to satisfy the demand for food of a growing human population but contributes to environmental degradation. However, there are technological options for agriculture to deliver food security and potentially reduce atmospheric CO₂.

To reduce climate warming we must stop adding CO₂ to the atmopshere, and develop approaches for removing it. Adding crushed, fast-reacting silicate rocks to croplands could improve productivity, restore soil quality and reduce atmospheric CO₂.

Enhanced rock weathering is competitive with other carbon sequestration strategies in terms of land, energy and water use with its overall sustainability dependent on that of the energy system supplying it, according to a process-based life cycle assessment.