Environmental sciences

  • Perspective |

    The future of Antarctica and the Southern Ocean by 2070 is described under two scenarios, one in which action is taken to limit greenhouse gas emissions, and one in which no action is taken.

    • S. R. Rintoul
    • , S. L. Chown
    •  & J. C. Xavier
  • Letter |

    A global analysis of gross primary productivity reveals that drought recovery is driven by climate and carbon cycling, with recovery longest in the tropics and high northern latitudes, and with impacts increasing over the twentieth century.

    • Christopher R. Schwalm
    • , William R. L. Anderegg
    •  & Hanqin Tian
  • Letter |

    Deforestation increases the odds of a species being threatened by extinction, and this effect is disproportionately strong in relatively intact landscapes, suggesting that efforts are needed to protect intact forest landscapes and prevent a new wave of extinctions.

    • Matthew G. Betts
    • , Christopher Wolf
    •  & Taal Levi
  • Article |

    Investigations of an Icelandic volcanic eruption confirm that sulfate aerosols caused a discernible yet transient brightening effect, as predicted, but their effect on the liquid water path was unexpectedly negligible.

    • Florent F. Malavelle
    • , Jim M. Haywood
    •  & Thorvaldur Thordarson
  • Perspective |

    The current and expected environmental consequences of built dams and proposed dam constructions in the Amazon basin are explored with the help of a Dam Environmental Vulnerability Index.

    • Edgardo M. Latrubesse
    • , Eugenio Y. Arima
    •  & Jose C. Stevaux
  • Letter |

    Options for achieving multiple sustainability goals in land systems are limited, and integrated national-scale analyses are needed across the broader environment and economy to prioritize efficient sustainability interventions.

    • Lei Gao
    •  & Brett A. Bryan
  • Letter |

    Global food consumption drives irrigation for crops, which depletes aquifers in some regions; here we quantify the volumes of groundwater depletion associated with global food production and international trade.

    • Carole Dalin
    • , Yoshihide Wada
    •  & Michael J. Puma
  • Letter |

    Field measurements combined with remotely sensed data reveal the Cuvette Centrale in the central Congo Basin to contain the most extensive peatland complex in the tropics, increasing the best estimate of global tropical peatland carbon stocks by approximately one-third.

    • Greta C. Dargie
    • , Simon L. Lewis
    •  & Suspense A. Ifo
  • Letter |

    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 |

    During much of the last ice age, continental ice sheets prevented humans from migrating into North America from Siberia; an environmental reconstruction of the corridor that opened up between the Cordilleran and Laurentide ice sheets reveals that it would have been inhospitable to the initial colonizing humans, who therefore probably entered North America by a different route.

    • Mikkel W. Pedersen
    • , Anthony Ruter
    •  & Eske Willerslev
  • Letter |

    Data from over 2,500 reefs worldwide is used to identify 15 bright spots—sites where reef biomass is significantly higher than expected—and surveys of local experts in these areas suggest that strong sociocultural institutions and high levels of local engagement are among the factors supporting higher fish biomass.

    • Joshua E. Cinner
    • , Cindy Huchery
    •  & David Mouillot
  • Letter |

    The evaporation and atmospheric oxidation of low-volatility organic vapours from mined oil sands material is shown to be responsible for a large amount of secondary organic aerosol mass—which affects air quality and climate change—observed during airborne measurements in Canada.

    • John Liggio
    • , Shao-Meng Li
    •  & Drew R. Gentner
  • Letter
    | Open Access

    The growth of nucleated organic particles has been investigated in controlled laboratory experiments under atmospheric conditions; initial growth is driven by organic vapours of extremely low volatility, and accelerated by more abundant vapours of slightly higher volatility, leading to markedly different modelled concentrations of atmospheric cloud condensation nuclei when this growth mechanism is taken into account.

    • Jasmin Tröstl
    • , Wayne K. Chuang
    •  & Urs Baltensperger
  • Letter |

    Two ring-like structures made of low walls of broken stalagmite pieces, deep in a cave in France, are described and dated to around 176,000 years ago, suggesting human-made construction within the period of early Neanderthals, although the function of the structures remains conjectural.

    • Jacques Jaubert
    • , Sophie Verheyden
    •  & Frédéric Santos
  • Letter |

    Aircraft measurements, laboratory photolysis experiments and modelling calculations reveal a mechanism for the recycling of nitric acid into nitrogen oxides; this enables observations to be reconciled with model studies, and suggests that particulate nitrate photolysis could be a substantial tropospheric nitrogen oxide source.

    • Chunxiang Ye
    • , Xianliang Zhou
    •  & Christoph Knote
  • Perspective |

    The potential of soils to mitigate greenhouse gas emissions has not been exploited; here we discuss and recommend research and technology developments to implement mitigation practices.

    • Keith Paustian
    • , Johannes Lehmann
    •  & Pete Smith
  • Letter |

    Using a global coupled biogeochemistry–climate model and a chemistry and transport model reveals that China’s present-day global radiative forcing is about ten per cent of the current global total, made up of both warming and cooling contributions; if in the future China reduces the cooling forcings, global warming could accelerate.

    • Bengang Li
    • , Thomas Gasser
    •  & Feng Zhou
  • Letter |

    The net balance of terrestrial biogenic greenhouse gases produced as a result of human activities and the climatic impact of this balance are uncertain; here the net cumulative impact of the three greenhouse gases, methane, nitrous oxide and carbon dioxide, on the planetary energy budget from 2001 to 2010 is a warming of the planet.

    • Hanqin Tian
    • , Chaoqun Lu
    •  & Steven C. Wofsy
  • Letter |

    Analyses of the effects of extreme weather disasters on global crop production over the past five decades show that drought and extreme heat reduced national cereal production by 9–10%, whereas no discernible effect at the national level was seen for floods and extreme cold; droughts affect yields and the harvested area, whereas extreme heat mainly affects yields.

    • Corey Lesk
    • , Pedram Rowhani
    •  & Navin Ramankutty
  • Review Article |

    The fossil record provides a nuanced view of ecosystem collapse over intervals of mass extinction, with abundant, biomineralizing and widespread species preferentially preserved; here the authors collate evidence for ‘mass rarity’ during these intervals, and suggest that the increasing rarity of modern species, rather than their outright extinction, may be a better metric for comparing the current biodiversity crisis to the ‘Big Five’ mass extinctions in the Earth’s history.

    • Pincelli M. Hull
    • , Simon A. F. Darroch
    •  & Douglas H. Erwin
  • Letter |

    Data from the long-running Park Grass Experiment is used to show that grassland biodiversity is recovering since UK atmospheric nitrogen levels started to decline 25 years ago in all but the most acidic soils.

    • J. Storkey
    • , A. J. Macdonald
    •  & M. J. Crawley
  • Perspective |

    Instead of containing stable and chemically unique ‘humic substances’, as has been widely accepted, soil organic matter is a mixture of progressively decomposing organic compounds; this has broad implications for soil science and its applications.

    • Johannes Lehmann
    •  & Markus Kleber
  • Perspective |

    Soil biodiversity sustains human health and its loss can be mitigated by sustainable management.

    • Diana H. Wall
    • , Uffe N. Nielsen
    •  & Johan Six
  • Letter |

    Assessment of mangrove forest surface elevation changes across the Indo-Pacific coastal region finds that almost 70 per cent of the sites studied do not have enough sediment availability to offset predicted sea-level rise; modelling indicates that such sites could be submerged as early as 2070.

    • Catherine E. Lovelock
    • , Donald R. Cahoon
    •  & Tran Triet
  • Article |

    Ground-sourced tree density data is assembled to provide a global map of tree density, which reveals that there are three trillion trees (tenfold more than previous estimates); tree numbers have declined by nearly half since the start of human civilization and over 15 billion trees are lost on an annual basis.

    • T. W. Crowther
    • , H. B. Glick
    •  & M. A. Bradford
  • Letter |

    Measurements of sediments eroded by the Mackenzie River reveal the widespread export of permafrost-derived biospheric carbon that is several thousand years old, and demonstrate its burial in the Arctic Ocean, suggesting that high-latitude rivers can act as important carbon dioxide sinks.

    • Robert G. Hilton
    • , Valier Galy
    •  & Damien Calmels