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The efficiency with which plants use carbon assimilated through photosynthesis has a key role in determining natureʼs capacity to offset carbon dioxide emissions. This study leverages global eddy covariance observations and ecological theory to reveal the patterns of vegetation carbon use efficiency worldwide.

An analysis of 24,202 critical cases of COVID-19 identifies potentially druggable targets in inflammatory signalling (JAK1), monocyte–macrophage activation and endothelial permeability (PDE4A), immunometabolism (SLC2A5 and AK5), and host factors required for viral entry and replication (TMPRSS2 and RAB2A).

This study finds that vegetation models commonly underestimate the productivity of West African forests, owing to bias in fractional absorbed photosynthetic radiation (fAPAR) and leaf level photosynthetic capacities.

Lower CO₂ and more-frequent fires may have supported grassland expansion in the Amazon during the Last Glacial Maximum, according to vegetation modelling using a range of boundary conditions tested against existing pollen records.

Meta-analyses in up to 1.3 million individuals identify 87 rare-variant associations with blood pressure traits. On average, rare variants exhibit effects ~8 times larger than the mean effects of common variants and implicate candidate causal genes at associated regions.

A global network of researchers was formed to investigate the role of human genetics in SARS-CoV-2 infection and COVID-19 severity; this paper reports 13 genome-wide significant loci and potentially actionable mechanisms in response to infection.

Analysis of peatland carbon accumulation over the last millennium and its association with global-scale climate space indicates an ongoing carbon sink into the future, but with decreasing strength as conditions warm.

Whole-genome sequencing, transcriptome-wide association and fine-mapping analyses in over 7,000 individuals with critical COVID-19 are used to identify 16 independent variants that are associated with severe illness in COVID-19.

Using global flux tower observations, the authors show that atmospheric dryness always reduces photosynthesis, whereas soil dryness can increase photosynthesis if soil water stores are sufficient.

The fraction of leaf nitrogen allocated to RuBisCO indicates differing nitrogen use strategies of plants and varies considerably. Here the authors show that this variation is largely driven by leaf thickness and phosphorus content with light intensity, atmospheric dryness and soil pH also having considerable influence.

Remotely sensed vegetation and water-balance measurements from 190 river basins across Australia show that sub-humid and semi-arid basins are ‘greening’—as expected under CO₂ fertilization—increasing water consumption and reducing streamflow.

Blanket bog—characterized by an almost complete landscape covering of undecayed organic peat—is a highly distinctive biome restricted to regions that experience hyperoceanic climatic conditions. Bioclimatic modelling suggests there will be a dramatic shrinkage of the available climatic space for blanket bogs with only a few, restricted areas of persistence.

Year-to-year variability in atmospheric CO₂ is strongly influenced by the terrestrial biosphere. Despite increasing anthropogenic emissions, Keenan et al. report a recent pause in the growth rate of atmospheric CO₂using observations and vegetation models, attributed to an enhanced terrestrial carbon sink.

The authors found that the key elements of plant form and function, analysed at global scale, are largely concentrated into a two-dimensional plane indexed by the size of whole plants and organs on the one hand, and the construction costs for photosynthetic leaf area, on the other.

The uptake of CO2 by leaves, and its conversion to sugars, is the basis for life on land. This study proposes a model unifying light-use efficiency relationships and a standard model of photosynthesis across species and ecosystems, and globally.

Soil moisture effects can substantially reduce photosynthesis and amplify the impacts of extreme events on primary production, potentially leading to biases in satellite-based estimates of photosynthesis, suggests an analysis of ground-based measurements.

Whether Amazonia is a carbon-dioxide source or sink has a significant effect on estimates of the global carbon budget. On an annual basis, El Niño, and its influence on precipitation in the region, seems to be a controlling factor.

Global patterns and trends in primary production are estimated using remote-sensing-based models. This Perspective outlines ways to ensure that the next generation of model predictions robustly characterizes how this key element of the terrestrial carbon cycle is changing.

The recent FACE model–data synthesis project used data from two FACE experiments to assess land ecosystem models. This Perspective details the 'assumption-centered' approach used to identify and evaluate the causes of model differences.

Elevated CO₂ increases plant biomass, providing a negative feedback on global warming. Nutrient availability was found to drive the magnitude of this effect for the majority of vegetation globally, and analyses indicated that CO₂ will continue to fertilize plant growth in the next century.

Efforts to control climate change require the stabilization of atmospheric carbon dioxide concentrations. An assessment of the trends in sources and sinks of atmospheric carbon dioxide suggests that the sinks are not keeping up with the increase in carbon dioxide emissions, but uncertainties are still large.

Yunke Peng et al. use in-situ measurements and leaf trait data at 266 global sites for 1637 species and find that the maximum rate of carboxylation standardized to 25 °C is proportional to growing-season irradiance, and covaries with area-based leaf nitrogen and area-based phosphorus on the species level. These results challenge the assumption that leaf-level photosynthetic capacity depends on soil N supply yet supports the relationship between photosynthesis and soil P supply.

Integrating natural selection and other organizing principles into next-generation vegetation models could render them more theoretically sound and useful for earth system applications and modelling climate impacts.

Stomatal conductance is a land-surface attribute that links the water and carbon cycles. Analysis of a global database covering a wide range of plant functional types and biomes now provides a framework for predicting the behaviour of stomatal conductance that can be applied to model ecosystem productivity, energy balance and ecohydrological processes in a changing climate.

Two important aims of mitigation policy are to maintain land carbon stocks and reduce terrestrial ecosystem-based emissions. This Perspective discusses the scientific issues involved, argues that current negotiations under the United Nations Framework Convention on Climate Change are not solidly grounded in science, and proposes some ways forward.

Rachel Freathy and colleagues report results of a large-scale genome-wide association study of birth weight. They identify four loci newly associated with this trait and find overlap between birth weight–associated loci and those influencing adult height and metabolism.