Forest ecology

  • Article
    | Open Access

    Tree species that are expanding their distribution in response to climate change could be hindered or facilitated by disturbances. Here the authors analyse forest inventory data from the western US to test the hypothesis that wildfire can facilitate climate-induced range shifts in trees.

    • Avery P. Hill
    •  & Christopher B. Field
  • Article
    | Open Access

    Defoliating insects disrupt nutrient cycling of boreal catchments by redistributing carbon and nitrogen from forests to lakes. The resulting shift in lake biogeochemistry exceeds broader between-year trends observed across the boreal and north temperate region.

    • Samuel G. Woodman
    • , Sacha Khoury
    •  & Andrew J. Tanentzap
  • Article
    | Open Access

    Climate change is expected to have major impacts on forest tree diseases. Here the authors analyse long-term data of white pine blister rust in the southern Sierra Nevada, finding evidence of climate change-driven disease range expansion that was mediated by spatially varying host-pathogen-drought interactions.

    • Joan Dudney
    • , Claire E. Willing
    •  & John J. Battles
  • Article
    | Open Access

    Mangroves are adapted to cope with tropical storms, but might be threatened by rising frequency and intensity of these events. Here the authors document one of the largest mangrove diebacks on record following Hurricane Irma in Florida, and show a greater role of storm surge and ponding rather than wind as a mechanism for mangrove dieback.

    • David Lagomasino
    • , Temilola Fatoyinbo
    •  & Douglas C. Morton
  • Article
    | Open Access

    The role of non-structural carbohydrates (NSC) in mediating the impacts of drought in tropical trees is unclear. Here, the authors analyse leaf and branch NSC in 82 Amazon tree species across a Basin-wide precipitation gradient, finding that allocation of leaf NSC to soluble sugars is higher in drier sites and is coupled to tree hydraulic status.

    • Caroline Signori-Müller
    • , Rafael S. Oliveira
    •  & David Galbraith
  • Article
    | Open Access

    Natural disturbances imperil healthy and productive forests, but quantifying their effects at large scales is challenging. Here the authors apply machine learning to disturbance records and satellite data to quantify and map European forest vulnerability to fires, windthrows, and insect outbreaks through 1979-2018.

    • Giovanni Forzieri
    • , Marco Girardello
    •  & Alessandro Cescatti
  • Article
    | Open Access

    The long-term effectiveness of assisted gene flow of trees could be jeopardised by rapid climate change. Here the authors analyse a large dataset of relocated black spruce populations in Canada, finding that local adaptation to climate of origin improved NPP responses, but only for up to ~15 years after planting.

    • Martin P. Girardin
    • , Nathalie Isabel
    •  & Patrick Lenz
  • Article
    | Open Access

    Tree mortality is increasing with climate change, which suggests that the biomass of dead wood is likely becoming more and more important to the global carbon cycle. Here, the authors perform a meta-analysis of the carbon content of dead wood and find that past estimates of total forest carbon were overestimated.

    • Adam R. Martin
    • , Grant M. Domke
    •  & Sean C. Thomas
  • Article
    | Open Access

    Cloud cover and scarcity of ground-based validation hinder remote sensing of forest dynamics in the Amazon basin. Here, the authors analyse imagery from a high-frequency geostationary satellite sensor to study monthly NDVI patterns in the Amazon forest, finding support for spatially extensive seasonality.

    • Hirofumi Hashimoto
    • , Weile Wang
    •  & Ramakrishna R. Nemani
  • Article
    | Open Access

    The nature of forest disturbances are changing, yet consequences for forest dynamics remain uncertain. Using a new index, Stanke et al. show the populations of over half of the most abundant tree species in the western US have declined in the last two decades, with grim implications for how temperate forests globally will respond to sustained anthropogenic and natural stress.

    • Hunter Stanke
    • , Andrew O. Finley
    •  & David W. MacFarlane
  • Article
    | Open Access

    The 2012–2016 drought and western pine beetle outbreaks caused unprecedented mortality of ponderosa pine in the Sierra Nevada, California. Here, the authors analyse drone-based data from almost half a million trees and find an interaction between host size and climatic water deficit, with higher mortality for large trees in dry, warm conditions but not in cooler or wetter conditions.

    • Michael J. Koontz
    • , Andrew M. Latimer
    •  & Malcolm P. North
  • Article
    | Open Access

    Evergreen conifers rely on ‘sustained quenching’ to protect their photosynthetic machinery during long, cold winters. Here, Bag et al. show that direct energy transfer (spillover) from photosystem II to photosystem I triggered by loss of grana stacking in chloroplast is the major component of sustained quenching in Scots pine.

    • Pushan Bag
    • , Volha Chukhutsina
    •  & Stefan Jansson
  • Article
    | Open Access

    Quantifying forest degradation and biodiversity losses is necessary to inform conservation and restoration policies. Here the authors analyze a large dataset for the Atlantic Forest in South America to quantify losses in forest biomass and tree species richness, functional traits, and conservation value.

    • Renato A. F. de Lima
    • , Alexandre A. Oliveira
    •  & Paulo I. Prado
  • Article
    | Open Access

    Mapping and quantifying degree of forest modification is critical to conserve and manage forests. Here the authors propose a new quantitative metric for landscape integrity and apply it to a global forest map, showing that less than half of the world’s forest cover has high integrity, most of which is outside nationally designed protected areas.

    • H. S. Grantham
    • , A. Duncan
    •  & J. E. M. Watson
  • Article
    | Open Access

    Droughts pose an increasingly important threat to forests. Here the authors analyse a high-resolution Landsat-based dataset of forest canopy mortality in Europe over 1987–2016 to show that drought is already a major driver of tree mortality.

    • Cornelius Senf
    • , Allan Buras
    •  & Rupert Seidl
  • Article
    | Open Access

    Tree mortality has been shown to be the dominant control on carbon storage in Amazon forests, but little is known of how and why Amazon forest trees die. Here the authors analyse a large Amazon-wide dataset, finding that fast-growing species face greater mortality risk, but that slower-growing individuals within a species are more likely to die, regardless of size.

    • Adriane Esquivel-Muelbert
    • , Oliver L. Phillips
    •  & David Galbraith
  • Article
    | Open Access

    Correlations between tree species diversity and tree abundance are well established, but the direction of the relationship is unresolved. Here the authors use path models to estimate plausible causal pathways in the diversity-abundance relationship across 23 global forests regions, finding a lack of general support for a positive diversity-abundance relationship, which is prevalent in the most productive lands on Earth only

    • Jaime Madrigal-González
    • , Joaquín Calatayud
    •  & Markus Stoffel
  • Article
    | Open Access

    Many models assume a universal carbon use efficiency across forest biomes, in contrast to assumptions of other process-based models. Here the authors analyse forest production efficiency across a wide range of climates to show a positive relationship with annual temperature and precipitation, indicating that ecosystem models are overestimating forest carbon losses under warming.

    • A. Collalti
    • , A. Ibrom
    •  & I. C. Prentice
  • Article
    | Open Access

    Tropical rainforests partly create their own climatic conditions by promoting precipitation, therefore rainforest losses may trigger dramatic shifts. Here the authors combine remote sensing, hydrological modelling, and atmospheric moisture tracking simulations to assess forest-rainfall feedbacks in three major tropical rainforest regions on Earth and simulate potential changes under a severe climate change scenario.

    • Arie Staal
    • , Ingo Fetzer
    •  & Obbe A. Tuinenburg
  • Article
    | Open Access

    Salvage logging has become a common practice to gain economic returns from naturally disturbed forests, but it could have considerable negative effects on biodiversity. Here the authors use a recently developed statistical method to estimate that ca. 75% of the naturally disturbed forest should be left unlogged to maintain 90% of the species unique to the area.

    • Simon Thorn
    • , Anne Chao
    •  & Alexandro B. Leverkus
  • Article
    | Open Access

    Mapping ecological variables using machine-learning algorithms based on remote-sensing data has become a widespread practice in ecology. Here, the authors use forest biomass mapping as a study case to show that the most common model validation approach, which ignores data spatial structure, leads to overoptimistic assessment of model predictive power.

    • Pierre Ploton
    • , Frédéric Mortier
    •  & Raphaël Pélissier
  • Article
    | Open Access

    The universality of the trade-off between early growth and lifespan in trees and its implications are disputed. Analysing a global tree ring dataset and performing data-driven simulations, the authors demonstrate the pervasiveness of the trade-off and challenge current earth system models that predict a continuation of the carbon sink into mature forests under warming and increasing CO2.

    • R. J. W. Brienen
    • , L. Caldwell
    •  & E. Gloor
  • Article
    | Open Access

    Different aspects of biodiversity may not necessarily converge in their response to climate change. Here, the authors investigate 25-year shifts in taxonomic, functional and phylogenetic diversity of tropical forests along a spatial climate gradient in West Africa, showing that drier forests are less stable than wetter forests.

    • Jesús Aguirre-Gutiérrez
    • , Yadvinder Malhi
    •  & Imma Oliveras
  • Article
    | Open Access

    Associations with mycorrhizal fungi can affect the outcome of plant competition in complex ways. Here the authors use a decade-long field survey and two hyphal exclusion experiments to reveal a critical role of underground fungal networks in facilitating seedling growth and fitness of ectomycorrhizal plants but not arbuscular mycorrhizal plants.

    • Minxia Liang
    • , David Johnson
    •  & Xubing Liu
  • Article
    | Open Access

    Microbial plant-soil feedbacks (PSF) are fundamentally important for plant diversity. The authors present a spatially explicit dynamic model that separates the effects of microbial mutualists and pathogens, thereby presenting a testable mechanistic framework to reconcile previously puzzling observations of the strength and direction of PSF with diversity maintenance.

    • John W. Schroeder
    • , Andrew Dobson
    •  & Edward Allen Herre
  • Article
    | Open Access

    Resilience to drought is crucial for tree survival under climate change. Here, DeSoto et al. show that trees that died during drought were less resilient to previous dry events compared to surviving conspecifics, but the resilience strategies differ between angiosperms and gymnosperms.

    • Lucía DeSoto
    • , Maxime Cailleret
    •  & Jordi Martínez-Vilalta
  • Article
    | Open Access

    The contribution of symbiotic dinitrogen fixation to the forest carbon sink could change throughout forest succession. Here the authors model nitrogen cycling and light competition between trees based on data from Panamanian forest plots, showing that fixation contributes substantially to the carbon sink in early successional stages.

    • Jennifer H. Levy-Varon
    • , Sarah A. Batterman
    •  & Lars O. Hedin
  • Article
    | Open Access

    Improving estimates of forest biomass based on remote sensing data is important to assess global carbon cycling. Here the authors develop an approach to use forest gap models to simulate lidar waveforms and compare the outputs with ICESAT-1 GLAS profiles, showing improved estimates across the Amazon basin.

    • Edna Rödig
    • , Nikolai Knapp
    •  & Andreas Huth
  • Article
    | Open Access

    Satellite-borne radar systems are promising tools to obtain spatial habitat data with complete geographic coverage. Here the authors show that freely available Sentinel-1 radar data perform as well as standard airborne laser scanning data for mapping biodiversity of 12 taxa across temperate forests in Germany.

    • Soyeon Bae
    • , Shaun R. Levick
    •  & Jörg Müller
  • Article
    | Open Access

    The defaunation of vertebrates may disrupt forest functioning through the loss of plant-animal interactions, but impacts on forests remain unquantified. Here the authors show that seed dispersal is a key interaction and defaunation of primates and birds negatively impacts forest regeneration.

    • Charlie J. Gardner
    • , Jake E. Bicknell
    •  & Zoe G. Davies
  • Article
    | Open Access

    Drought is intensifying due to climate change, impacting forests globally. Here, the authors track nearly 2 million trees through severe drought and show that tree height is the greatest predictor of mortality risk, suggesting that the tallest trees may be the most vulnerable.

    • Atticus E. L. Stovall
    • , Herman Shugart
    •  & Xi Yang
  • Article
    | Open Access

    Understanding mechanisms of soil organic matter (SOM) decomposition and stabilisation improves soil-climate feedback predictions. Here the authors show that roots in boreal forest promote organic nitrogen economy and provide a framework on how roots affect decomposition and stabilisation of SOM.

    • Bartosz Adamczyk
    • , Outi-Maaria Sietiö
    •  & Jussi Heinonsalo
  • Article
    | Open Access

    Kong et al. use a global trait dataset of 800 plant species to examine the root economics spectrum in relation to root diameter, tissue density and root nitrogen concentration. Nonlinear trait relationships were observed, suggesting allometry-based nonlinearity in root trait relationships.

    • Deliang Kong
    • , Junjian Wang
    •  & Yulong Feng
  • Article
    | Open Access

    Fertilization under greenhouse warming conditions is expected to accelerate tree growth and potentially increase the biological storage of CO2. Here the authors analyse ring width measurements from 1768 conifers from the Spanish and Russian mountains and demonstrate that longevity requires slow growth rates at least in mountainous regions.

    • Ulf Büntgen
    • , Paul J. Krusic
    •  & Christian Körner
  • Article
    | Open Access

    Here, Schuldt et al. collate data from two long-term grassland and forest biodiversity experiments to ask how plant diversity facets affect the diversity of higher trophic levels. The results show that positive effects of plant diversity on consumer diversity are mediated by plant structural and functional diversity, and vary across ecosystems and trophic levels.

    • Andreas Schuldt
    • , Anne Ebeling
    •  & Nico Eisenhauer
  • Article
    | Open Access

    Given the potential for increasingly common and intense tropical storms, it is important to understand their effects on island forest communities. Here, the authors show that Hurricane María’s strength and rainfall had larger effects on tree mortality than other less severe storms, and that large trees and species with low-density wood were most susceptible.

    • María Uriarte
    • , Jill Thompson
    •  & Jess K. Zimmerman
  • Article
    | Open Access

    Separating anthropogenic and climatic impacts on forest compositions can be challenging due to a lack of data. Here the authors look at forest compositional changes in eastern Canada since the 19th century and find land use has most strongly shaped communities towards disturbance-adapted species.

    • Victor Danneyrolles
    • , Sébastien Dupuis
    •  & Dominique Arseneault
  • Article
    | Open Access

    There has been recent interest in understanding why the biodiversity-productivity relationship varies among studies and across scales. Here Fei et al. show that climatic variation drives forest biodiversity-productivity relationships at large spatial scales, whilst biotic and abiotic factors are important in given climate units.

    • Songlin Fei
    • , Insu Jo
    •  & Eckehard G. Brockerhoff
  • Article
    | Open Access

    Increases in tree mortality can signal changes in forest health, but large-scale tree mortality is difficult to quantify. Here Senf et al. show large-scale increases in forest mortality in Central Europe over the past 30 years, which were related to increasing growing stocks and temperature.

    • Cornelius Senf
    • , Dirk Pflugmacher
    •  & Rupert Seidl
  • Article
    | Open Access

    Managing forests for the supply of multiple ecosystem services (ES) is key given potential trade-offs among services. Here, the authors analyse how forest stand attributes generate trade-offs among ES and the relative contribution of forest attributes and environmental factors to predict services.

    • María R. Felipe-Lucia
    • , Santiago Soliveres
    •  & Eric Allan
  • Article
    | Open Access

    Climate change may impact forest disturbances, though local variability is high. Here, Sommerfeld et al. show that disturbance patterns across the temperate biome vary with agents and tree traits, yet large disturbances are consistently linked to warmer and drier than average conditions.

    • Andreas Sommerfeld
    • , Cornelius Senf
    •  & Rupert Seidl
  • Article
    | Open Access

    The productivity of boreal forests in Eastern North America is predicted to increase with warming under sufficient moisture supply. Here D’Orangeville et al. study seven tree species and predict that growth enhancements may be seen up to 2 °C warming, but would decline if temperatures exceed this.

    • Loïc D’Orangeville
    • , Daniel Houle
    •  & Daniel Kneeshaw
  • Article
    | Open Access

    Biodiversity change can impact ecosystem functioning, though this is primarily studied at lower trophic levels. Here, Schuldt et al. find that biodiversity components other than tree species richness are particularly important, and higher trophic level diversity plays a role in multifunctionality.

    • Andreas Schuldt
    • , Thorsten Assmann
    •  & Helge Bruelheide
  • Article
    | Open Access

    Recent measurements in the Amazon rainforest indicate missing sources of volatile organic compounds (VOCs). Here the authors show that soil microorganisms are a strong, unaccounted source of highly reactive sesquiterpenes, a class of VOCs that can regulate ozone chemistry within the forest canopy.

    • E. Bourtsoukidis
    • , T. Behrendt
    •  & J. Williams