Biogeochemistry

  • Article
    | Open Access

    The early Earth’s atmosphere had very low oxygen levels for hundreds of millions of years, until the 2.4 Ga Great Oxidation Event, which remains poorly understood. Here, the authors show that reducing Archean volcanic gases could have prevented atmospheric O2 from accumulating, and therefore mantle oxidation was likely very important in setting the evolution of O2 and aerobic life.

    • Shintaro Kadoya
    • , David C. Catling
    • , Robert W. Nicklas
    • , Igor S. Puchtel
    •  & Ariel D. Anbar
  • Article
    | Open Access

    Biology can profoundly influence the planet’s climate, but over Earth’s long history these effects are poorly constrained. Here the authors show that on early Earth, the evolution of microbes producing and consuming methane likely controlled warming and glacial events, and thus Earth’s habitability

    • Boris Sauterey
    • , Benjamin Charnay
    • , Antonin Affholder
    • , Stéphane Mazevet
    •  & Régis Ferrière
  • Article
    | Open Access

    Anthropogenic CO2 is acidifying the ocean, but knowledge of the carbonate properties underlying these dynamics in coastal oceans is lacking. Here, the authors reveal spatial distribution patterns and variability in carbonate chemistry along North America’s coasts.

    • Wei-Jun Cai
    • , Yuan-Yuan Xu
    • , Richard A. Feely
    • , Rik Wanninkhof
    • , Bror Jönsson
    • , Simone R. Alin
    • , Leticia Barbero
    • , Jessica N. Cross
    • , Kumiko Azetsu-Scott
    • , Andrea J. Fassbender
    • , Brendan R. Carter
    • , Li-Qing Jiang
    • , Pierre Pepin
    • , Baoshan Chen
    • , Najid Hussain
    • , Janet J. Reimer
    • , Liang Xue
    • , Joseph E. Salisbury
    • , José Martín Hernández-Ayón
    • , Chris Langdon
    • , Qian Li
    • , Adrienne J. Sutton
    • , Chen-Tung A. Chen
    •  & Dwight K. Gledhill
  • Article
    | Open Access

    The ubiquitous oceanic bacteria harbour an external phosphate buffer for modulating phosphate (Pi) uptake. Here, using both oceanic SAR11, Prochlorococcus and Synechococcus strains as a model, the authors show that the Pi buffer accumulation in the periplasm is proton motive force-dependent and can be enhanced by light energy.

    • Nina A. Kamennaya
    • , Kalotina Geraki
    • , David J. Scanlan
    •  & Mikhail V. Zubkov
  • Article
    | Open Access

    Warming is expected to increase C sink capacity in high-latitude ecosystems, but plant-herbivore interactions could moderate or offset this effect. Here, Silfver and colleagues test individual and interactive effects of warming and insect herbivory in a field experiment in Subarctic forest, showing that even low intensity insect herbivory strongly reduces C sink potential.

    • Tarja Silfver
    • , Lauri Heiskanen
    • , Mika Aurela
    • , Kristiina Myller
    • , Kristiina Karhu
    • , Nele Meyer
    • , Juha-Pekka Tuovinen
    • , Elina Oksanen
    • , Matti Rousi
    •  & Juha Mikola
  • Article
    | Open Access

    Snow algae bloom along the coast of Antarctica and are likely to be biogeochemically important. Here, the authors produced the first map of such blooms, show that they are driven by warmer temperatures and proximity to birds and mammals, and are likely to increase given projected climate changes.

    • Andrew Gray
    • , Monika Krolikowski
    • , Peter Fretwell
    • , Peter Convey
    • , Lloyd S. Peck
    • , Monika Mendelova
    • , Alison G. Smith
    •  & Matthew P. Davey
  • Review Article
    | Open Access

    Coastal systems are hotspots of ecological, geochemical and economic activity, yet their dynamics are not accurately represented in global models. In this Review, Ward and colleagues assess the current state of coastal science and recommend approaches for including the coastal interface in predictive models.

    • Nicholas D. Ward
    • , J. Patrick Megonigal
    • , Ben Bond-Lamberty
    • , Vanessa L. Bailey
    • , David Butman
    • , Elizabeth A. Canuel
    • , Heida Diefenderfer
    • , Neil K. Ganju
    • , Miguel A. Goñi
    • , Emily B. Graham
    • , Charles S. Hopkinson
    • , Tarang Khangaonkar
    • , J. Adam Langley
    • , Nate G. McDowell
    • , Allison N. Myers-Pigg
    • , Rebecca B. Neumann
    • , Christopher L. Osburn
    • , René M. Price
    • , Joel Rowland
    • , Aditi Sengupta
    • , Marc Simard
    • , Peter E. Thornton
    • , Maria Tzortziou
    • , Rodrigo Vargas
    • , Pamela B. Weisenhorn
    •  & Lisamarie Windham-Myers
  • Article
    | Open Access

    Plants are known to be influenced by climate, topsoil conditions, and ecology, but the impact of features deeper in the Earth system are poorly understood. Here, the authors show that primary productivity is controlled in part by deep bedrock characteristics far below the roots.

    • Zihan Jiang
    • , Hongyan Liu
    • , Hongya Wang
    • , Jian Peng
    • , Jeroen Meersmans
    • , Sophie M. Green
    • , Timothy A. Quine
    • , Xiuchen Wu
    •  & Zhaoliang Song
  • Article
    | Open Access

    Plastic pollution has infiltrated every ecosystem, but few studies have quantified the biogeochemical or ecological effects of plastic. Here the authors show that microplastics in ocean sediment can significantly alter microbial community structure and nitrogen cycling.

    • Meredith E. Seeley
    • , Bongkeun Song
    • , Renia Passie
    •  & Robert C. Hale
  • Article
    | Open Access

    One-third of Earth’s carbon is sequestered in peatlands, and its stability in the face of climate change is unknown. Here the authors show that warming leads to the release of carbon as methane, but only the most prolonged warming leads to the breakdown and release of deep, old carbon.

    • A. M. Hopple
    • , R. M. Wilson
    • , M. Kolton
    • , C. A. Zalman
    • , J. P. Chanton
    • , J. Kostka
    • , P. J. Hanson
    • , J. K. Keller
    •  & S. D. Bridgham
  • Article
    | Open Access

    Identification of stratospheric volcanic eruptions in the geological record and their link to mass extinction events during the past 540 million years remains challenging. Here, the authors report unexpected, large mass-independent sulphur isotopic compositions of pyrite in Late Ordovician sedimentary rocks, which they suggest originates from stratospheric volcanism linked to the first pulse of the Late Ordovician mass extinction.

    • Dongping Hu
    • , Menghan Li
    • , Xiaolin Zhang
    • , Alexandra V. Turchyn
    • , Yizhe Gong
    •  & Yanan Shen
  • Article
    | Open Access

    CH4 seepage mostly occurs in petroleum-bearing sedimentary basins, but the role of tectonics in degassing is mostly only known at a local scale. Here, the authors conduct a global scale analysis of seeps, faults, sedimentary basins, petroleum fields and heat flow, and find that geological CH4 seepage preferably develops in convergent basins, while gas seeps can occur along any brittle tectonic structure.

    • Giancarlo Ciotoli
    • , Monia Procesi
    • , Giuseppe Etiope
    • , Umberto Fracassi
    •  & Guido Ventura
  • Article
    | Open Access

    Reactive iron minerals protect vast amounts of terrestrial carbon from decomposition and release as CO2. Here the authors show that reactive iron alone does not provide sufficient protection except under strict oxic conditions—instead, iron itself promotes carbon decomposition.

    • Chunmei Chen
    • , Steven J. Hall
    • , Elizabeth Coward
    •  & Aaron Thompson
  • Article
    | Open Access

    Generally it is thought that confining clay layers provide protection to low-arsenic groundwaters against intrusion of shallower, high-arsenic groundwater bodies. Here, the authors show that impermeable clay layers can increase arsenic input to underlying groundwater systems due to reduction of iron oxides coupled to carbon oxidation.

    • Ivan Mihajlov
    • , M. Rajib H. Mozumder
    • , Benjamín C. Bostick
    • , Martin Stute
    • , Brian J. Mailloux
    • , Peter S. K. Knappett
    • , Imtiaz Choudhury
    • , Kazi Matin Ahmed
    • , Peter Schlosser
    •  & Alexander van Geen
  • Article
    | Open Access

    Previous work suggests that marine oxygen levels and bioturbation are important factors that shape phosphorus burial and the size of the marine biosphere. Here the authors show that seawater calcium concentration is a key factor in controlling marine P burial, and thus the global oxygen cycle.

    • Mingyu Zhao
    • , Shuang Zhang
    • , Lidya G. Tarhan
    • , Christopher T. Reinhard
    •  & Noah Planavsky
  • Article
    | Open Access

    Threats to marine ecosystems are increasing due to ocean acidification, but trends are spatiotemporally difficult to monitor or predict. Here the authors use an Earth system model to accurately predict surface pH changes in the economically and ecologically important California Current System.

    • Riley X. Brady
    • , Nicole S. Lovenduski
    • , Stephen G. Yeager
    • , Matthew C. Long
    •  & Keith Lindsay
  • Article
    | Open Access

    Many inland waters seasonally or permanently dry up, thus exposing sediments to the atmosphere. Here the authors show that a substantial amount of CO2 is emitted from these dry sediments, increasing current inland water carbon flux estimates by 6%.

    • P. S. Keller
    • , N. Catalán
    • , D. von Schiller
    • , H.-P. Grossart
    • , M. Koschorreck
    • , B. Obrador
    • , M. A. Frassl
    • , N. Karakaya
    • , N. Barros
    • , J. A. Howitt
    • , C. Mendoza-Lera
    • , A. Pastor
    • , G. Flaim
    • , R. Aben
    • , T. Riis
    • , M. I. Arce
    • , G. Onandia
    • , J. R. Paranaíba
    • , A. Linkhorst
    • , R. del Campo
    • , A. M. Amado
    • , S. Cauvy-Fraunié
    • , S. Brothers
    • , J. Condon
    • , R. F. Mendonça
    • , F. Reverey
    • , E.-I. Rõõm
    • , T. Datry
    • , F. Roland
    • , A. Laas
    • , U. Obertegger
    • , J.-H. Park
    • , H. Wang
    • , S. Kosten
    • , R. Gómez
    • , C. Feijoó
    • , A. Elosegi
    • , M. M. Sánchez-Montoya
    • , C. M. Finlayson
    • , M. Melita
    • , E. S. Oliveira Junior
    • , C. C. Muniz
    • , L. Gómez-Gener
    • , C. Leigh
    • , Q. Zhang
    •  & R. Marcé
  • Article
    | Open Access

    Biosphere productivity is an important component of the CO2 cycle, but how it has varied over past glacial-interglacial cycles is not well known. Here, the authors present new data that shows that global biosphere productivity was 10 to 30% higher during Termination V compared to younger deglaciations.

    • Margaux Brandon
    • , Amaelle Landais
    • , Stéphanie Duchamp-Alphonse
    • , Violaine Favre
    • , Léa Schmitz
    • , Héloïse Abrial
    • , Frédéric Prié
    • , Thomas Extier
    •  & Thomas Blunier
  • Article
    | Open Access

    Plants respond to increasing CO2 concentrations in the atmosphere by stomatal closure which causes a reduction of evapotranspiration and thus latent heat flux. Here, the authors show that this CO2 physiological forcing strengthens Arctic warming through increasing sea ice loss and local feedbacks.

    • So-Won Park
    • , Jin-Soo Kim
    •  & Jong-Seong Kug
  • Article
    | Open Access

    Bacteria capable of anaerobic ammonium oxidation (anammox) produce half of the nitrogen gas in the atmosphere, but much of their physiology is still unknown. Here the authors show that anammox bacteria are capable of a novel mechanism of ammonium oxidation using extracellular electron transfer.

    • Dario R. Shaw
    • , Muhammad Ali
    • , Krishna P. Katuri
    • , Jeffrey A. Gralnick
    • , Joachim Reimann
    • , Rob Mesman
    • , Laura van Niftrik
    • , Mike S. M. Jetten
    •  & Pascal E. Saikaly
  • Article
    | Open Access

    DMSP is a ubiquitous organosulfur compound in the ocean that, once degraded by bacteria, plays key roles in global biogeochemical cycles and climate regulation. Here, the authors use single-cell measurements of transcription to investigate the intricate dynamics of bacterial DMSP degradation.

    • Cherry Gao
    • , Vicente I. Fernandez
    • , Kang Soo Lee
    • , Simona Fenizia
    • , Georg Pohnert
    • , Justin R. Seymour
    • , Jean-Baptiste Raina
    •  & Roman Stocker
  • Article
    | Open Access

    Rice paddies are a major source of the Earth’s atmospheric methane, making these important food crops potent contributors to greenhouse gas emissions. Here the authors show that inoculation of paddies with a particular bacterium could significantly curb methane production.

    • Vincent V. Scholz
    • , Rainer U. Meckenstock
    • , Lars Peter Nielsen
    •  & Nils Risgaard-Petersen
  • Article
    | Open Access

    In recent history the amount of carbon captured by terrestrial systems has increased, but the processes driving this process has remained poorly constrained. Here the authors use a global carbon model to show that a decrease in wildfires has caused the land carbon sink to increase in the past few decades.

    • Yi Yin
    • , A. Anthony Bloom
    • , John Worden
    • , Sassan Saatchi
    • , Yan Yang
    • , Mathew Williams
    • , Junjie Liu
    • , Zhe Jiang
    • , Helen Worden
    • , Kevin Bowman
    • , Christian Frankenberg
    •  & David Schimel
  • Article
    | Open Access

    Trypanosoma brucei guanosine 5′-monophosphate reductase (TbGMPR) catalyses the conversion of GMP to inosine 5′-monophosphate and contains a cystathionine-β-synthase (CBS) domain. Here the authors combine X-ray crystallography and kinetic measurements and present the GMP-, GTP-bound and nucleotide-free TbGMPR structures and show that guanine and adenine nucleotides are allosteric regulators of TbGMPR that bind to the CBS domain.

    • Akira Imamura
    • , Tetsuya Okada
    • , Hikaru Mase
    • , Takuya Otani
    • , Tomoka Kobayashi
    • , Manatsu Tamura
    • , Bruno Kilunga Kubata
    • , Katsuaki Inoue
    • , Robert P. Rambo
    • , Susumu Uchiyama
    • , Kentaro Ishii
    • , Shigenori Nishimura
    •  & Takashi Inui
  • Article
    | Open Access

    High latitude droughts are increasing, but their effects on freshwater systems are poorly understood. Here the authors investigate Sweden’s most severe drought in the last century and show that these dry conditions induce hypoxia and elevated methane production from streams.

    • Lluís Gómez-Gener
    • , Anna Lupon
    • , Hjalmar Laudon
    •  & Ryan A. Sponseller
  • Article
    | Open Access

    The Late Ordovician mass extinction has been attributed to extended marine anoxia. Here, the authors use a metal isotope mass balance model and find the marine anoxic event lasted over 3 million years, notably longer than the anoxic event associated with the Permian-Triassic extinction and Cretaceous ocean anoxic events.

    • Richard G. Stockey
    • , Devon B. Cole
    • , Noah J. Planavsky
    • , David K. Loydell
    • , Jiří Frýda
    •  & Erik A. Sperling
  • Article
    | Open Access

    Arctic plant growth is predominantly nitrogen limited, where the slow nitrogen turnover in the soil is commonly attributed to the cold arctic climate. Here the authors show that the arctic plant-soil nitrogen cycling is also constrained by the lack of larger detritivores like earthworms.

    • Gesche Blume-Werry
    • , Eveline J. Krab
    • , Johan Olofsson
    • , Maja K. Sundqvist
    • , Maria Väisänen
    •  & Jonatan Klaminder
  • Article
    | Open Access

    Earth’s surface underwent a dramatic transition ~2.3 billion years ago when atmospheric oxygen first accumulated during the Great Oxidation Event. Here, the authors find that biogenic methane and volcanic emissions played a vital role in the reduced Late Archean atmosphere.

    • Aubrey L. Zerkle
    • , Runsheng Yin
    • , Chaoyue Chen
    • , Xiangdong Li
    • , Gareth J. Izon
    •  & Stephen E. Grasby
  • Article
    | Open Access

    Earth’s drylands are expected to expand due to climate change, but how this will affect vegetation remains unclear. Here the authors use models to show that despite expansion, primary productivity in drylands is likely to increase through the 21st Century.

    • Jingyu Yao
    • , Heping Liu
    • , Jianping Huang
    • , Zhongming Gao
    • , Guoyin Wang
    • , Dan Li
    • , Haipeng Yu
    •  & Xingyuan Chen
  • Article
    | Open Access

    The release of ancient carbon from thawing permafrost is thought to have an important impact on global biogeochemistry through positive feedbacks. Here Dean and colleagues show that in Siberian permafrost, warming could liberate more contemporary carbon relative to aged counterparts.

    • Joshua F. Dean
    • , Ove H. Meisel
    • , Melanie Martyn Rosco
    • , Luca Belelli Marchesini
    • , Mark H. Garnett
    • , Henk Lenderink
    • , Richard van Logtestijn
    • , Alberto V. Borges
    • , Steven Bouillon
    • , Thibault Lambert
    • , Thomas Röckmann
    • , Trofim Maximov
    • , Roman Petrov
    • , Sergei Karsanaev
    • , Rien Aerts
    • , Jacobus van Huissteden
    • , Jorien E. Vonk
    •  & A. Johannes Dolman
  • Article
    | Open Access

    While a large quantity of underground mineral resources can be converted into manufactured products, a majority is still solid waste disposal. Here the authors found a large increase in total weight of anthropogenic mineral from 2010 to 2050 with faster growth rate for precious metals.

    • Xianlai Zeng
    • , Saleem H. Ali
    • , Jinping Tian
    •  & Jinhui Li
  • Article
    | Open Access

    Global atmospheric CO2 varies between glacial–interglacial cycles. Here, the authors study these changes using Si records and how the Si flux and ocean circulation changes controlled the global Si distribution across the last deglaciation, based on high-resolution Si-isotope records from the Indian Sector Southern Ocean.

    • M. Dumont
    • , L. Pichevin
    • , W. Geibert
    • , X. Crosta
    • , E. Michel
    • , S. Moreton
    • , K. Dobby
    •  & R. Ganeshram
  • Article
    | Open Access

    Coastal pollution degrades ecosystems, but long term impacts are unknown in Australia’s Great Barrier Reef. Using a 333 year record of coral skeleton nitrogen isotopes, Erler and colleagues show that increasing nutrient inputs since European settlement have led to unexpected feedback responses.

    • Dirk V. Erler
    • , Hanieh Tohidi Farid
    • , Thomas D. Glaze
    • , Natasha L. Carlson-Perret
    •  & Janice M. Lough
  • Article
    | Open Access

    In this study, the authors show that water flowing through thawed soils below the tundra surface (supra-permafrost groundwater) can be a major source of dissolved organic matter (DOM) to Arctic coastal waters during the summer. This DOM contains leachates from old soil carbon stocks, including potential contributions from thawing permafrost.

    • Craig T. Connolly
    • , M. Bayani Cardenas
    • , Greta A. Burkart
    • , Robert G. M. Spencer
    •  & James W. McClelland
  • Article
    | Open Access

    Complex macroscopic organisms are first found in the Ediacaran period, but their ecology during this time is not well understood. Here, Bobrovskiy et al. analyse biomarkers from Ediacaran sediments hosting macrofossils and find evidence for abundant algal food sources available for these organisms.

    • Ilya Bobrovskiy
    • , Janet M. Hope
    • , Elena Golubkova
    •  & Jochen J. Brocks
  • Article
    | Open Access

    There lacks research to figure out the variations in sources, magnitude, and spatiotemporal patterns of Nr flows in urban system. Here the authors develop a coupled human-natural urban nitrogen flow analysis model and show that anthropogenic perturbations not only intensify Nr input to sustain increasing demands for production and consumption of cities, but also greatly change the Nr distribution pattern in the urban system.

    • Yue Dong
    • , Linyu Xu
    • , Zhifeng Yang
    • , Hanzhong Zheng
    •  & Lei Chen
  • Article
    | Open Access

    The Southern Ocean is an important sink of carbon via the biological pump. Here authors run high-resolution physical/biogeochemical simulations of an open-Southern Ocean ecosystem forced with a realistic seasonal cycle and confirm that (sub)mesoscale iron transport across the mixing-layer base sustains primary productivity.

    • Takaya Uchida
    • , Dhruv Balwada
    • , Ryan P. Abernathey
    • , Galen A. McKinley
    • , Shafer K. Smith
    •  & Marina Lévy
  • Article
    | Open Access

    Palm oil biofuels are touted as a sustainable alternative to fossil fuels. Meijide and colleagues use greenhouse gas measurements to update life cycle assessments of oil palm growth scenarios and show that despite the promise, emission savings do not meet sustainability standards.

    • Ana Meijide
    • , Cristina de la Rua
    • , Thomas Guillaume
    • , Alexander Röll
    • , Evelyn Hassler
    • , Christian Stiegler
    • , Aiyen Tjoa
    • , Tania June
    • , Marife D. Corre
    • , Edzo Veldkamp
    •  & Alexander Knohl
  • Article
    | Open Access

    Eddies are common ocean features that isolate large swaths of seawater, but it is unclear how they influence productivity of phytoplankton trapped inside. Here Ellwood and colleagues use stable and radiogenic isotopes to characterize a Southern Ocean eddy, finding vanishingly low iron concentrations that drive low productivity across the region.

    • Michael J. Ellwood
    • , Robert F. Strzepek
    • , Peter G. Strutton
    • , Thomas W. Trull
    • , Marion Fourquez
    •  & Philip W. Boyd
  • Article
    | Open Access

    Ammonia oxidizing archaea and Nitrospinae are the main known nitrifiers in the ocean, but the much greater abundance of the former is puzzling. Here, the authors show that differences in mortality, rather than thermodynamics, cell size or biomass yield, explain the discrepancy, without the need to invoke yet undiscovered, abundant nitrite oxidizers.

    • Katharina Kitzinger
    • , Hannah K. Marchant
    • , Laura A. Bristow
    • , Craig W. Herbold
    • , Cory C. Padilla
    • , Abiel T. Kidane
    • , Sten Littmann
    • , Holger Daims
    • , Petra Pjevac
    • , Frank J. Stewart
    • , Michael Wagner
    •  & Marcel M. M. Kuypers
  • Article
    | Open Access

    Plants are thought to be limited by phosphorus (P) especially in tropical regions. Here, Hou et al. report a meta-analysis of P fertilization experiments to show widespread P limitation on plant growth across terrestrial ecosystems modulated by climate, ecosystem properties, and fertilization regimes

    • Enqing Hou
    • , Yiqi Luo
    • , Yuanwen Kuang
    • , Chengrong Chen
    • , Xiankai Lu
    • , Lifen Jiang
    • , Xianzhen Luo
    •  & Dazhi Wen
  • Article
    | Open Access

    The role of paddy rice agriculture in the spatial and temporal dynamics of atmospheric methane concentration remains unclear. Here, Zhang et al. show that regions with dense rice paddies have high satellite-based column averaged CH4 concentrations (XCH4), and that seasonal dynamics of XCH4 mirror those of paddy rice growth.

    • Geli Zhang
    • , Xiangming Xiao
    • , Jinwei Dong
    • , Fengfei Xin
    • , Yao Zhang
    • , Yuanwei Qin
    • , Russell B. Doughty
    •  & Berrien Moore III
  • Article
    | Open Access

    The influence of the Congo River margin on surface Fe concentrations is understudied. Here the authors show that such influence is evident over 1000 km from the Congo outflow.

    • Lúcia H. Vieira
    • , Stephan Krisch
    • , Mark J. Hopwood
    • , Aaron J. Beck
    • , Jan Scholten
    • , Volker Liebetrau
    •  & Eric P. Achterberg
  • Article
    | Open Access

    In this study, the authors investigate thermal alteration of organic biomarkers to detect paleo earthquakes in the Japan Trench. The study shows that large earthquakes like the 2011 Tohoku-Oki earthquake can slip through different types of sediment rather than being restricted to the weakest layers.

    • Hannah S. Rabinowitz
    • , Heather M. Savage
    • , Pratigya J. Polissar
    • , Christie D. Rowe
    •  & James D. Kirkpatrick
  • Article
    | Open Access

    Despite growing aquaculture production and environmental concerns on phosphorus (P) enrichment, the P budgets of fisheries have been largely overlooked. Here, Huang et al. calculate global fishery P budgets and estimate P use efficiency for a wide range of aquaculture systems.

    • Yuanyuan Huang
    • , Phillipe Ciais
    • , Daniel S. Goll
    • , Jordi Sardans
    • , Josep Peñuelas
    • , Fabio Cresto-Aleina
    •  & Haicheng Zhang
  • Article
    | Open Access

    Wetlands are global hotspots of carbon storage, but errors exist with current estimates of the extent of their carbon density. Here the authors show that mangrove sediment organic carbon stock has previously been overestimated, while ecosystem carbon stock has been underestimated.

    • Xiaoguang Ouyang
    •  & Shing Yip Lee
  • Article
    | Open Access

    Cloudinomorphs were one of the few groups to survive from the Ediacaran into the Cambrian, but they are known only from their external tubes. Here, Schiffbauer et al. report soft-tissue preservation of cloudinomorphs; the internal structures are interpreted as guts characteristic of bilaterians.

    • James D. Schiffbauer
    • , Tara Selly
    • , Sarah M. Jacquet
    • , Rachel A. Merz
    • , Lyle L. Nelson
    • , Michael A. Strange
    • , Yaoping Cai
    •  & Emily F. Smith
  • Article
    | Open Access

    In this study, the authors use planktic foraminiferal data to reconstruct ocean carbonate chemistry and temperature from 16.5 to 11 Ma from a size in the tropical eastern Indian Ocean to look at the causes of the Monterey Excursion (ME). They find a positive relationship between dissolved inorganic (DIC) carbon and the ME and a negative one for DIC and the carbon maxima events.

    • S. M. Sosdian
    • , T. L. Babila
    • , R. Greenop
    • , G. L. Foster
    •  & C. H. Lear
  • Article
    | Open Access

    Recent recession of the Larsen Ice Shelf C has revealed that microbial alteration of illite can occur within marine sediments, a process previously thought to only occur abiotically during low-grade metamorphism. Here, the authors show that such microbial alteration of illite could provide a potential source of Fe release to Southern Ocean waters during Holocene glacial cycles.

    • Jaewoo Jung
    • , Kyu-Cheul Yoo
    • , Brad E. Rosenheim
    • , Tim M. Conway
    • , Jae Il Lee
    • , Ho Il Yoon
    • , Chung Yeon Hwang
    • , Kiho Yang
    • , Christina Subt
    •  & Jinwook Kim