Featured
-
-
Article |
Authigenic mineral phases as a driver of the upper-ocean iron cycle
Analysis of a new dissolved iron, ligand and particulate iron seasonal dataset shows that authigenic iron phases help control ocean dissolved iron distributions and the coupling between dissolved and particulate iron pools.
- Alessandro Tagliabue
- , Kristen N. Buck
- & Peter Sedwick
-
Article |
Uncovering the Ediacaran phosphorus cycle
Reconstruction of oceanic phosphorus concentrations during a large negative carbon-isotope excursion co-occurring with global oceanic oxygenation and evolution of some of Earth’s earliest animals suggests that decoupled phosphorus and ocean anoxia cycles during the Ediacaran may have prolonged the rise of atmospheric oxygen.
- Matthew S. Dodd
- , Wei Shi
- & Timothy W. Lyons
-
Article
| Open AccessSafe and just Earth system boundaries
We find that justice considerations constrain the integrated Earth system boundaries more than safety considerations for climate and atmospheric aerosol loading, and our assessment provides a foundation for safeguarding the global commons for all people.
- Johan Rockström
- , Joyeeta Gupta
- & Xin Zhang
-
Article |
Indian Ocean salinity build-up primes deglacial ocean circulation recovery
Salinity reconstructions show that Indian Ocean surface salinity increased during glacial periods and that the release of this water via the Agulhas Leakage during deglaciation can trigger abrupt changes in the Atlantic Meridional Overturning Circulation.
- Sophie Nuber
- , James W. B. Rae
- & Stephen Barker
-
Article |
Basin-scale reconstruction of euxinia and Late Devonian mass extinctions
A spatial and temporal compilation of geochemical data documents a stepwise transgression of toxic euxinic waters into shallow oceans that drove a series of Late Devonian extinction events.
- Swapan K. Sahoo
- , Geoffrey J. Gilleaudeau
- & Alan J. Kaufman
-
Article |
Optimal nitrogen rate strategy for sustainable rice production in China
A proposed optimal nitrogen rate strategy together with analysis of an extensive on-farm dataset shows that meeting national rice production targets in 2030 in China is possible while concurrently reducing nationwide nitrogen consumption.
- Siyuan Cai
- , Xu Zhao
- & Xiaoyuan Yan
-
Article
| Open AccessCost-effective mitigation of nitrogen pollution from global croplands
A meta-analysis of 1,521 field observations from the past two decades led to the identification of 11 key measures to cost-effectively mitigate nitrogen pollution from global croplands.
- Baojing Gu
- , Xiuming Zhang
- & Deli Chen
-
Article |
Widespread herbivory cost in tropical nitrogen-fixing tree species
Nitrogen-fixing trees are favoured by herbivorous animals relative to non-fixing trees, increasing their carbon opportunity cost and potentially constraining global nitrogen fixation.
- Will Barker
- , Liza S. Comita
- & Sarah A. Batterman
-
Article |
From planetary to regional boundaries for agricultural nitrogen pollution
Modelling of regional and planetary boundaries for agricultural nitrogen pollution finds that the global nitrogen surplus boundary is lower than the current nitrogen surplus.
- L. F. Schulte-Uebbing
- , A. H. W. Beusen
- & W. de Vries
-
Article |
Global trends of cropland phosphorus use and sustainability challenges
The historical and spatial patterns of the phosphorus budget and phosphorus use efficiency by country and crop type are reported, and used to determine phosphorus pollution and scarcity challenges.
- T. Zou
- , X. Zhang
- & E. A. Davidson
-
Article
| Open AccessEnhanced silica export in a future ocean triggers global diatom decline
Mesocosm experiments in different biomes show that future ocean acidification will slow down the dissolution of biogenic silica, decreasing silicic acid availability in the surface ocean and triggering a global decline of diatoms as revealed by Earth system model simulations.
- Jan Taucher
- , Lennart T. Bach
- & Ulf Riebesell
-
Article |
Baleen whale prey consumption based on high-resolution foraging measurements
A combination of 3D whale locations and acoustic measurements of prey density is used here to show that whales’ consumption of krill is several times larger than often thought.
- Matthew S. Savoca
- , Max F. Czapanskiy
- & Jeremy A. Goldbogen
-
Article |
Structure of Geobacter pili reveals secretory rather than nanowire behaviour
Structural, functional and localization studies reveal that Geobacter sulfurreducens pili cannot behave as microbial nanowires, instead functioning in a similar way to secretion pseudopili to export cytochrome nanowires that are essential for extracellular electron transfer.
- Yangqi Gu
- , Vishok Srikanth
- & Nikhil S. Malvankar
-
Article |
A 200-million-year delay in permanent atmospheric oxygenation
Sulfur isotope and iron–sulfur–carbon systematics on marine sediments indicate that permanent atmospheric oxygenation occurred around 2.22 billion years ago, about 100 million years later than currently estimated.
- Simon W. Poulton
- , Andrey Bekker
- & David T. Johnston
-
Article
| Open AccessAnaerobic endosymbiont generates energy for ciliate host by denitrification
‘Candidatus Azoamicus ciliaticola’ transfers energy to its ciliate host in the form of ATP and enables this host to breathe nitrate, demonstrating that eukaryotes with remnant mitochondria can secondarily acquire energy-providing endosymbionts.
- Jon S. Graf
- , Sina Schorn
- & Jana Milucka
-
Article |
Warming impairs trophic transfer efficiency in a long-term field experiment
In artificial ponds exposed to seven years of experimental warming, energy transfer between two trophic levels of freshwater plankton decreased by 56% and the biomass of both levels was reduced.
- Diego R. Barneche
- , Chris J. Hulatt
- & Gabriel Yvon-Durocher
-
Article |
Maximizing US nitrate removal through wetland protection and restoration
Analysis of US continental wetland inventory data combined with model simulations indicate that a spatially targeted 10% increase in wetland area could double wetland nitrogen removal.
- F. Y. Cheng
- , K. J. Van Meter
- & N. B. Basu
-
Article |
A comprehensive quantification of global nitrous oxide sources and sinks
Bottom-up and top-down approaches are used to quantify global nitrous oxide sources and sinks resulting from both natural and anthropogenic sources, revealing a 30% increase in global human-induced emissions between 1980 and 2016.
- Hanqin Tian
- , Rongting Xu
- & Yuanzhi Yao
-
Article |
Bacterial chemolithoautotrophy via manganese oxidation
A co-culture of two newly identified microorganisms—‘Candidatus Manganitrophus noduliformans’ and Ramlibacter lithotrophicus—exhibits exponential growth that is dependent on manganese(II) oxidation, demonstrating the viability of this metabolism for supporting life.
- Hang Yu
- & Jared R. Leadbetter
-
Article |
Recycling and metabolic flexibility dictate life in the lower oceanic crust
Analyses of microbial communities that live 10–750 m below the seafloor at Atlantis Bank, Indian Ocean, provide insights into how these microorganisms survive by coupling energy sources to organic and inorganic carbon resources.
- Jiangtao Li
- , Paraskevi Mara
- & Virginia P. Edgcomb
-
Article |
Light-driven anaerobic microbial oxidation of manganese
Anoxygenic photosynthetic microorganisms can biomineralize manganese oxides without molecular oxygen being present and without high-potential photosynthetic reaction centres, which sheds doubt on proposed dates for the origins of oxygenic photosynthetic metabolism.
- Mirna Daye
- , Vanja Klepac-Ceraj
- & Tanja Bosak
-
Letter |
Climate change and overfishing increase neurotoxicant in marine predators
Overfishing and warming ocean temperature have caused an increase in methylmercury concentrations in some Atlantic predatory fish, and this trend is predicted to continue unless stronger mercury and carbon emissions standards are imposed.
- Amina T. Schartup
- , Colin P. Thackray
- & Elsie M. Sunderland
-
Letter |
Managing nitrogen to restore water quality in China
Estimates of spatial patterns of nitrogen discharge into water bodies across China between 1955 and 2014 show that current discharge rates are almost three times the acceptable threshold, and ways to restore a clean water environment are suggested.
- ChaoQing Yu
- , Xiao Huang
- & James Taylor
-
Article |
Convergent estimates of marine nitrogen fixation
Convergent estimates of nitrogen fixation from an inverse biogeochemical and a prognostic ocean model show that biological carbon export in the ocean is higher than expected and that stabilizing nitrogen-cycle feedbacks are weaker than we thought.
- Wei-Lei Wang
- , J. Keith Moore
- & François W. Primeau
-
Letter |
Industrial and agricultural ammonia point sources exposed
Satellite observations reveal over 200 ammonia hotspots associated with agricultural and industrial point sources, which emit much larger quantities of ammonia to the atmosphere than previously thought.
- Martin Van Damme
- , Lieven Clarisse
- & Pierre-François Coheur
-
Letter |
Triple oxygen isotope evidence for limited mid-Proterozoic primary productivity
Triple oxygen isotope measurements of 1.4-billion-year-old sedimentary sulfates reveal a unique mid-Proterozoic atmosphere and demonstrate that gross primary productivity in the mid-Proterozoic was between 6% and 41% of pre-anthropogenic levels.
- Peter W. Crockford
- , Justin A. Hayles
- & Boswell A. Wing
-
Letter |
Carbonate-sensitive phytotransferrin controls high-affinity iron uptake in diatoms
Phytotransferrin, a functional analogue of transferrin, has an obligate requirement for carbonate to bind iron, which suggests that acidification-driven declines in the concentration of seawater carbonate ions may negatively affect diatom iron acquisition.
- Jeffrey B. McQuaid
- , Adam B. Kustka
- & Andrew E. Allen
-
Letter |
Pervasive phosphorus limitation of tree species but not communities in tropical forests
In lowland tropical forests in Panama, widespread species-level phosphorus limitation of tree growth is not reflected in community-wide growth or biomass owing to the presence of a few species tolerant of low phosphorus availability.
- Benjamin L. Turner
- , Tania Brenes-Arguedas
- & Richard Condit
-
Letter |
Pursuing sustainable productivity with millions of smallholder farmers
Millions of Chinese smallholder farmers were persuaded to adopt enhanced management practices, which led to a greater yield, reduced nitrogen fertilizer use and improved environmental performance throughout China.
- Zhenling Cui
- , Hongyan Zhang
- & Zhengxia Dou
-
Letter |
Fire frequency drives decadal changes in soil carbon and nitrogen and ecosystem productivity
A meta-analysis and field data show that frequent fires in savannas and broadleaf forests decrease soil carbon and nitrogen over many decades; modelling shows that nitrogen loss drives carbon loss by reducing net primary productivity.
- Adam F. A. Pellegrini
- , Anders Ahlström
- & Robert B. Jackson
-
Letter |
Nutrient co-limitation at the boundary of an oceanic gyre
Nutrient amendment experiments at the boundary of the South Atlantic gyre reveal extensive regions in which nitrogen and iron are co-limiting, with other micronutrients also approaching co-deficiency; such limitations potentially increase phytoplankton community diversity.
- Thomas J. Browning
- , Eric P. Achterberg
- & C. Mark Moore
-
Letter |
The rise of algae in Cryogenian oceans and the emergence of animals
Steroid biomarkers provide evidence for a rapid rise of marine planktonic algae between 659 and 645 million years ago, establishing more efficient energy transfers and driving ecosystems towards larger and increasingly complex organisms.
- Jochen J. Brocks
- , Amber J. M. Jarrett
- & Tharika Liyanage
-
Letter |
Tundra uptake of atmospheric elemental mercury drives Arctic mercury pollution
A two-year study of mercury deposition in the Arctic finds that the main source of mercury is gaseous elemental mercury, which is deposited throughout the year and leads to very high soil mercury levels.
- Daniel Obrist
- , Yannick Agnan
- & Detlev Helmig
-
Letter |
Onset of the aerobic nitrogen cycle during the Great Oxidation Event
Nitrogen isotope data from sediments deposited during the earliest stage of the Great Oxidation Event show evidence for the emergence of a pervasive aerobic marine nitrogen cycle.
- Aubrey L. Zerkle
- , Simon W. Poulton
- & Christopher K. Junium
-
Letter |
Elevation alters ecosystem properties across temperate treelines globally
Examination of the ecosystem properties of treeline ecotones in seven temperate regions of the world shows that the reduction in temperature with increasing elevation does not affect tree leaf nutrient concentrations, but does reduce ground-layer community-weighted plant nitrogen levels, leading to a strong stoichiometric convergence of ground-layer plant community nitrogen to phosphorus ratios across all regions.
- Jordan R. Mayor
- , Nathan J. Sanders
- & David A. Wardle
-
Letter |
Evolution of the global phosphorus cycle
Low phosphorus burial in shallow marine sedimentary rocks before about 750 million years ago implies a change in the global phosphorus cycle, coinciding with the end of what may have been a stable low-oxygen world.
- Christopher T. Reinhard
- , Noah J. Planavsky
- & Kurt O. Konhauser
-
Letter |
Water balance creates a threshold in soil pH at the global scale
There is an abrupt transition from alkaline to acid soil pH when mean annual precipitation exceeds mean annual potential evapotranspiration, demonstrating that climate creates a nonlinear pattern in soil solution chemistry at the global scale.
- E. W. Slessarev
- , Y. Lin
- & O. A. Chadwick
-
Article |
SAR11 bacteria linked to ocean anoxia and nitrogen loss
Bacteria of the SAR11 clade constitute up to one half of all marine microbes and are thought to require oxygen for growth; here, a subgroup of SAR11 bacteria are shown to thrive in ocean oxygen minimum zones and to encode abundant respiratory nitrate reductases.
- Despina Tsementzi
- , Jieying Wu
- & Frank J. Stewart