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Carbohydrate reserves play a vital role in plant survival during periods of negative carbon balance. Under a carbon-limited scenario, we expect a trade-offs between carbon allocation to growth, reserves, and defense. A resulting hypothesis is that carbon allocation to reserves exhibits a coordinated variation with functional traits associated with the 'fast-slow' plant economics spectrum. We tested the relationship between non-structural carbohydrates (NSC) of tree organs and functional traits using 61 angiosperm tree species from temperate and tropical forests with phylogenetic hierarchical Bayesian models. Our results provide evidence that NSC concentrations in stems and branches are decoupled from plant functional traits. while those in roots are weakly coupled with plant functional traits. In contrast, we found that variation between NSC concentrations in leaves and the fast-slow trait spectrum was coordinated, as species with higher leaf NSC had trait values associated with resource conservative species, such as lower SLA, leaf N, and leaf P. We also detected a small effect of leaf habit on the variation of NSC concentrations in branches and roots. Efforts to predict the response of ecosystems to global change will need to integrate a suite of plant traits, such as NSC concentrations in woody organs, that are independent of the 'fast-slow' plant economics spectrum and that capture how species respond to a broad range of global change drivers. [ABSTRACT FROM AUTHOR]

Amazonian ecosystems are of global importance for the climate system and biodiversity. Phosphorus (P) is suggested to be a limited nutrient in many Amazonian ecosystems because soils are ancient, highly weathered, and nutrient depleted. Recently, it has been suggested that large herbivores may play a major role in the Amazon nutrient cycle. Here, we develop this hypothesis further and show how the spatial redistribution of P from rivers to land, across different ecosystems and between sub-basins may even sustain the Amazonian P cycle, and this not only by means of large herbivores, which supposedly were present previously to human arrival to the contient, but by different animal foraging strategies that exist today. To do so, we introduce a simple mathematical framework, which synthesizes the major processes of the Amazonian P cycle and allows for quantifying their relative contribution to the P budget. With this model we use sensitivity analyses to demonstrate how animals can affect the P cycle. Our findings suggest the importance of the interweaved Amazonian ecology, including fish migrations, different flooding and soil moisture regimes as well as the role of different animal foraging strategies for a sustainable P cycling in these ecosystems. [ABSTRACT FROM AUTHOR]