David Bauman

Read the full paper (open access) here: doi.org/10.1111/geb.70141
As for my fellow statistics/R/reproducible code lovers, you'll find the detailed commented R code (and data) for all analyses and figures here 🙃: zenodo.org/records/1704...
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We find that 🌳 demography is not uniform, even within a species’ range.
Accounting for this mosaic of mortality can improve management & conservation of forests facing intensifying stressors, and stresses the crucial role of permanent plots across environmental gradients. @umramap.bsky.social
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🌎 Take-home message:
To predict forest futures, we need to go beyond climate envelopes — including disturbances, pests, and ontogeny — if we want realistic models of mortality and carbon cycling.
@ird-fr.bsky.social
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In contrast, in low-mortality years, competition was the main mortality agent, suggesting a prevalence of gap dynamics under low mortality years and regions.
High-mortality patches, though, were dominated by disturbance agents like storms and insects.
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🔥 Pinus elliottii (slash pine) and P. palustris (longleaf pine) showed more localised spatial structures.
Extreme weather events (storms, mostly) and fire dominated their high-mortality years (especially 2013–2023).
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🌳 Pinus taeda (loblolly pine) stood out:
Its survival has clearly declined over the past two decades across its natural range.
This pattern was spatially consistent and mostly linked to weather, insects, and competition.
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We found that mortality patterns form a mosaic across space and time — and change in nonlinear ways with tree size (ontogeny).
👉 Most interspecific differences appear in saplings (2.5 to 10 cm DBH) and near maximum tree size.
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Tree mortality isn’t random — it depends on who you are, where you grow, and what happens to you.
We analysed demographic data from ~130,000 trees across 14,500 plots (years 2003–2023), looking at mortality agents like competition, storms, fire, insects, and disease.
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Mosaic of Size‐Dependent Mortality in Three Ecologically and Economically Important Pine Species Reveals Patterns Across Space and Time Aim Global forests face increasing stresses from novel climate states, altered disturbance regimes and the spread of pests and pathogens. Understanding where and when mortality occurs across species...

🌲 Very happy to share our new study on where, when, and why trees die across the range of 3 major southern US pines: Pinus taeda, P. palustris, and P. elliottii (loblolly, longleaf, and slash pine).
🔗 doi.org/10.1111/geb.70141
@ird-fr.bsky.social @umramap.bsky.social @ulbrecherche.bsky.social
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The unexpected influence of legacy conspecific density dependence The presence of dead conspecific neighbours significantly decreased tree survival. Negative legacy conspecific effects proved nearly four times stronger than living conspecific density effects. The l...

This follows our earlier Ecology Letters study showing that dead trees can influence neighbours even more than living ones.

Forests have long memories — the "ghosts" of trees past still shape who grows, survives, and coexists. 🌳🌱

🔗 doi.org/10.1111/ele....
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We’ve long known that young trees struggle near adults of the same species — this mechanism helps maintain diversity.
But what if that effect doesn’t end when the adult tree dies?

Turns out this "legacy effect" can last at least 5 years — even after the tree is dead 🌲
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Memories of Trees Past: Coexistence Implications of Legacy Conspecific Density Dependence Negative density dependence persisted for up to 5 years after tree death, but with interspecific variation. Although stabilising niche differences were large, fitness differences–at the seedling life...

🌳 New paper out in Ecology Letters! 🌱
Our latest study, led by Lukas Magee, shows that the “legacies” of trees continue to shape forests long after they die.

onlinelibrary.wiley.com/doi/10.1111/...

#Ecology #Forests #Biodiversity
@umramap.bsky.social @ird-fr.bsky.social
A thread: [1/3]

This is figure 3, which shows Queensland rainforest plot locations, long-term climate, and causal diagram of the hypotheses relating climate variations over time to ΔAGB.

A study in Nature reports that a transition from carbon sink to source for the aboveground woody biomass of moist tropical Australian forests has occurred, driven by increasingly extreme climate anomalies. go.nature.com/4ndWLmg ⚒️ 🧪

Ahead of the EU Council meeting on 23 Oct., > 2178 scientists across Europe have signed an open letter urging heads of state and government to back a
science-based 2040 climate target of > 90–95% domestic greenhouse gas
reductions compared to the 1990s.
doi.org/10.5281/zeno...
@ird-fr.bsky.social

Aboveground biomass in Australian tropical forests now a net carbon source - Nature A transition from carbon sink to source for the aboveground woody biomass of moist tropical Australian forests has occurred, driven by increasingly extreme climate anomalies.

Nature research paper: Aboveground biomass in Australian tropical forests now a net carbon source

go.nature.com/3KRZ9BB

🌳 Selon une nouvelle étude les forêts tropicales d’Australie seraient les premières au monde à émettre davantage de carbone dans l’atmosphère qu’elles n’en absorbent.

ℹ️ www.ird.fr/les-forets-t...

⚠️ Our @theconversation.com explainer of the @nature.com paper—what changed in aboveground woody biomass and why it matters.
Read 👇 theconversation.com/a-crucial-st...
@ird-fr.bsky.social @umramap.bsky.social @edinburgh-uni.bsky.social @oxfordgeography.bsky.social @oxfordecosystems.bsky.social

A research volunteer admires a large tree at a long-term research site in Australia’s tropical rainforest. Credit: Andrew Ford

With #COP30 next month in Belém 🇧🇷, we hope this will be a wake-up call: tropical forests are under growing pressure from climate change.
Safeguarding them demands ambitious and fair climate action, including stronger support for countries that protect these vital ecosystems for us all. 🌳🌡️📈
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Aerial view of Australia’s relict tropical rainforests, one of the oldest rainforests in the world. Credit: Alexander Shenkin

View through Australian old-growth tropical rainforest at a long-term research site, where individual trees are painted with identification numbers. Credit: Andrew Ford

Of course, this doesn’t mean these forests have lost all climate value ➡️ they remain immense carbon stores and irreplaceable biodiversity havens.
But it shows that keeping global warming well below 1.5 °C is now even harder—and more urgent. 🌏
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Tropical tree mortality has increased with rising atmospheric water stress - Nature Over the past 35 years, annual tree mortality risk has increased in the moist tropical forests of Australia and is associated with increased atmospheric water stress.

Context: in 2022, our @nature.com study found a long-term increase in tree mortality in these forests, likely due to rising atmospheric water stress.
🔗 nature.com/articles/s41586-022-04737-7
This new paper follows up: aboveground biomass is now a net carbon emitter — driven by #ClimateChange.
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Aerial view of Australia’s relict tropical rainforests. A 49-year study reveals that aboveground biomass in these forests has switched from being carbon sink to a carbon source. Credit: Alexander Shenkin @shenkin.bsky.social

Aerial view of tropical rainforest canopy in Australia. Credit: Alexander Shenkin @shenkin.bsky.social

Based on 50 yrs of data from ~11 000 trees, we found that the aboveground woody biomass—once absorbing C—now now releases nearly 1 tonne of C per hectare each year.
The cause? Human-driven climate change: hotter extremes, droughts & cyclones are killing more trees than the forest regrow. 🌡️🌪️
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Aboveground biomass in Australian tropical forests now a net carbon source - Nature A transition from carbon sink to source for the aboveground woody biomass of moist tropical Australian forests has occurred, driven by increasingly extreme climate anomalies.

🚨 New in @nature.com: Aboveground biomass in Australian tropical forests now a net carbon source.
Led by Hannah Carle, with @umramap.bsky.social @ird-fr.bsky.social @edinburgh-uni.bsky.social @umdscience.bsky.social @westsyduhie.bsky.social @creaf.cat
👉 nature.com/articles/s41586-025-09497-8
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Hello Bluesky! AMAP est une unité de recherche qui s'intéresse à la botanique et la modélisation de l'architecture des plantes et des végétations. AMAP regroupe des mathématiciens et informaticiens aux côtés de botanistes, agronomes & écologues 🌱🌿🌳🔬🛰️💻
amap.cirad.fr/fr/index.php
#helloESR #botany

Winner–loser plant trait replacements in human-modified tropical forests - Nature Ecology & Evolution Tropical forest landscapes are increasingly being modified by human activities. Here the authors apply a causal inference approach to Neotropical forest data to disentangle the role of landscape-level...

📄 Link to study: www.nature.com/articles/s41...
With @josbarlow.bsky.social , @fplmelo.bsky.social , @erikaberenguer.bsky.social , @ird-fr.bsky.social , Universidade Federal de Pernambuco, @ecioxford.bsky.social , Lancaster University, Universidade Estadual de Santa Cruz, and several others.
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Figure 1 of the study: Artistic causal diagram (Directed Acyclic Graph, #DAG) used in the study (design and drawings by Jannah Oliveira; obrigadão Jannah!) to illustrate our causal assumptions as to how the data-generation process underlying region-level human disturbance pressures, and tree community functional traits. This causal model was used to logically inform the content of our statistical models, with the aim to allow causal interpretations of the effects of interest. @ird-fr@bsky.social @oxfordecosystems.bsky.social

These findings show how #causality can be inferred from observational data in #Ecology. Habitat loss, fragmentation, edge effects, degradation, and the functional make-up of tree communities have interdependencies, and require a #CausalModel to disentangle #causation from spurious association!
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Recent #deforestation in an already deforested and degraded human-modified landscape in the #Amazon. Credit: Flavio Forner and Rede Amazônia Sustentável.

The hyper-fragmented landscape of the Serra Grande region in northeast Brazil, with forest fragments surrounded by sugar-cane plantations. Credit: Adriano Gambarini.

➡️ Highlights urgent need to conserve / restore #TropicalForests, prevent degradation, and implement measures to protect / boost populations of the large-bodied birds (e.g. toucans) and mammals (e.g. spider monkeys) that disperse the seeds of 'losing' slow-growing large-seeded tree species.
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An Agouti (Cutia sp.) carrying a large fruit of a Bertheletia excelsa (Brazil nut) in the Balbina region. Photo from a camera trap installed by Maíra Benchimol, one of the authors of the study.

A Tayra (Eira barbara) carrying a large fruit of a large-seeded Sapotaceae tree in the Balbina region. Photo from a camera trap installed by Maíra Benchimol, one of the authors of the study.

A logging patio helps demonstrate the extent of timber removal in the wider landscape in the Amazon. Credit: Flavio Forner and Rede Amazônia Sustentável.

These 'winner-loser replacements' along these gradients of increasing human disruption are also likely to impact wildlife species adapted to consuming / dispersing the large seeds of tree species being lost in human-modified landscapes.
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New paper out in @natureecoevo.bsky.social, led by Bruno Pinho, showing how human disruption is driving 'winner' and 'loser' #tree species shifts across tropical forests.
➡️ Fast-growing / small-seeded species dominating Brazilian forests were levels of deforestation and degradation are high.
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What a pleasure to be at #BES2024! Great presentations and people, but also lots of fun! I enjoyed presenting a poster on tropical #tree #demography and #ClimateChange, and discussing with colleagues, as well as people I met for the first time. My bowling 🎳, however, still needs a lot of work... 🙈

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