Search

Wood density is a key control on tree biomass, and understanding its spatial variation improves estimates of forest carbon stock. Sullivan et al. measure >900 forest plots to quantify wood density and produce high resolution maps of its variation across South American tropical forests.

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.

The authors analyse tree responses to an extreme heat and drought event across South America to understand long-term climate resistance. While no more sensitive to this than previous lesser events, forests in drier climates showed the greatest impacts and thus vulnerability to climate extremes.

Inventory data from more than 1 million trees across African, Amazonian and Southeast Asian tropical forests suggests that, despite their high diversity, just 1,053 species, representing a consistent ~2.2% of tropical tree species in each region, constitute half of Earth’s 800 billion tropical trees.

Analysing >1,700 inventory plots from the Amazon Tree Diversity Network, the authors show that the majority of Amazon tree species can occupy floodplains and that patterns of species turnover are closely linked to regional flood patterns.

Inventory data from 90 lowland Amazonian forest plots and a phylogeny of 526 angiosperm genera were used to show that taxonomic and phylogenetic diversity are both predictive of wood productivity but not of biomass variation.

Unlike Amazonian forests, African forests have maintained their carbon sink until recently but by 2030 the African carbon sink will have shrunk by 14 per cent and the Amazonian sink will reach almost zero.

The Amazon rainforest is dominated by relatively few tree species, yet the degree to which this hyperdominance influences carbon cycling remains unknown. Here, the authors analyse 530 forest plots and show that ∼1% of species are responsible for 50% of the aboveground carbon storage and productivity.

Most Amazon tree species are rare but a small proportion are common across the region. The authors show that different species are hyperdominant in different size classes and that hyperdominance is more phylogenetically restricted for larger canopy trees than for smaller understory ones.

The aboveground carbon stock of a montane African forest network is comparable to that of a lowland African forest network and two-thirds higher than default values for these montane forests.

Using 13 functional traits we characterize the Amazonian trees and the communities they form. Amazonian tree communities are distributed along a fast-slow-spectrum. This results in clear differences in traits among these forests, as well as their biomass and biomass productivity.

The capacity of Amazonian forests to sequester carbon has weakened with potentially important implications for climate change.

This study reports data from a network of long-term monitoring plots across African tropical forests, which finds that above-ground carbon storage in live trees increased by 0.63 Mg C ha⁻¹ yr⁻¹ between 1968 and 2007. The data is extrapolated to unmeasured forest components, and by scaling to the continent, a total increase in carbon storage in African tropical forest trees of 0.34 Pg C yr⁻¹ is estimated. These results provide evidence that increasing carbon storage in old-growth forests is a pan-tropical phenomenon.

Capacity for carbon capture and storage in forests may not be monolithic but instead a function of complex dynamics of forest strata and age. The smaller trees that make up the understory in African tropical forests store their carbon longer as compared to sub-canopy and canopy trees and they represent a disproportionately large share of the carbon sink, in spite of their small size.

Tree species turnover across Amazonian forests unveils sharp floristic transitional zones, that are linked with changes in soil fertility and climate.

A study mapping the tree species richness in Amazonian forests shows that soil type exerts a strong effect on species richness, probably caused by the areas of these forest types. Cumulative water deficit, tree density and temperature seasonality affect species richness at a regional scale.