Hyperdominance in Amazonian forest carbon cycling

Abstract

While Amazonian forests are extraordinarily diverse, the abundance of trees is skewed strongly towards relatively few ‘hyperdominant' species. In addition to their diversity, Amazonian trees are a key component of the global carbon cycle, assimilating and storing more carbon than any other ecosystem on Earth. Here we ask, using a unique data set of 530 forest plots, if the functions of storing and producing woody carbon are concentrated in a small number of tree species, whether the most abundant species also dominate carbon cycling, and whether dominant species are characterized by specific functional traits. We find that dominance of forest function is even more concentrated in a few species than is dominance of tree abundance, with only ≈1% of Amazon tree species responsible for 50% of carbon storage and productivity. Although those species that contribute most to biomass and productivity are often abundant, species maximum size is also influential, while the identity and ranking of dominant species varies by function and by region.

Tree Climbing Techniques and Volume Equations for Eschweilera (Matá-Matá), a Hyperdominant Genus in the Amazon Forest

“…The lower DBH classes concentrate 70% of the total volume per hectare ( Figure 6). Trees of the Eschweilera genus with a DBH ≥ 50 cm are rare and sparse [25,26,28,39,40]. Paragraph 3 of the CONAMA resolution allows for changes to the minimum diameter permitted for logging (DMC) [38].…”

Revisiting the ‘cornerstone of Amazonian conservation’: a socioecological assessment of Brazil nut exploitation

“…In Peru, harvesting of Brazil nut is both a financially attractive and complementary activity in ecotourism forest concessions (Kirby et al 2010) and biophysically compatible with low intensity timber harvesting (Rockwell et al 2015). Across its vast geographical range, the Brazil nut tree coexists with dozens of timber species (ter Steege et al 2013;Fauset et al 2015). And although integrated timber-Brazil nut management can be hampered due to policy, economic and technical constraints (Guariguata et al 2009;Cronkleton et al 2012b;Duchelle et al 2012;Rockwell et al 2015), many of these tradeoffs are not insurmountable.…”

“…In Peru, Brazil nut concessions store, as a land use type, the largest aboveground carbon densities across the country (110 Mg C ha -1 ; Asner et al 2014). And basinwide, Brazil nut trees rank third among the dominant top 20 tree species in terms of aboveground biomass (Fauset et al 2015) while being an ''hyperdominant'' element of the tree flora (ter Steege et al 2013). At the national level, Perús National Forest Conservation Program (http://www.bosques.gob.pe/grants) grants subsidies per hectare to native and indigenous communities holding large tracts of forest in exchange for avoiding deforestation and degradation (Börner et al 2016).…”

Arbuscular mycorrhizal community structure on co-existing tropical legume trees in French Guiana

“…We investigated three legume species in different tribes of the (Fauset et al 2015). The three species have contrasting root morphologies with Dicorynia guianensis and Tachigali melinonii being similar to one another with thin, highly branched roots in contrast to Eperua falcata that has thicker, poorly branching root systems with short roots on long axes (Béreau & Garbaye 1994).…”