RESUMEN
We tested the idea that functional trade-offs that underlie species tolerance to drought-driven shifts in community composition via their effects on demographic processes and subsequently on shifts in species' abundance. Using data from 298 tree species from tropical dry forests during the extreme ENSO-2015, we scaled-up the effects of trait trade-offs from individuals to communities. Conservative wood and leaf traits favoured slow tree growth, increased tree survival and positively impacted species abundance and dominance at the community-level. Safe hydraulic traits, on the other hand, were related to demography but did not affect species abundance and communities. The persistent effects of the conservative-acquisitive trade-off across organizational levels is promising for generalization and predictability of tree communities. However, the safety-efficient trade-off showed more intricate effects on performance. Our results demonstrated the complex pathways in which traits scale up to communities, highlighting the importance of considering a wide range of traits and performance processes.
Asunto(s)
Sequías , Clima Tropical , Humanos , Bosques , Árboles/fisiología , Madera , Hojas de la PlantaRESUMEN
Extreme drought events have negative effects on forest diversity and functioning. At the species level, however, these effects are still unclear, as species vary in their response to drought through specific functional trait combinations. We used long-term demographic records of 21,821 trees and extensive databases of traits to understand the responses of 338 tropical dry forests tree species to ENSO2015 , the driest event in decades in Northern South America. Functional differences between species were related to the hydraulic safety-efficiency trade-off, but unexpectedly, dominant species were characterised by high investment in leaf and wood tissues regardless of their leaf phenological habit. Despite broad functional trait combinations, tree mortality was more widespread in the functional space than tree growth, where less adapted species showed more negative net biomass balances. Our results suggest that if dry conditions increase in this ecosystem, ecological functionality and biomass gain would be reduced.
Asunto(s)
Sequías , Clima Tropical , Ecosistema , Bosques , América del Norte , Hojas de la Planta , Árboles , AguaRESUMEN
A new species of sponge-dwelling snapping shrimp, Synalpheus amintae sp. nov. from the Parque Nacional Natural Isla Gorgona, Pacific coast of Colombia, is described. This new species pertains to the denominated Synalpheus "Gambarelloides" species group sensu Coutière (1909)-previously known as "Laevimanus" group. It was collected in the southern part of the Island, during episodes of extreme low tides, known locally as "puja". Synalpheus amintae sp. nov. is closely related to the only two other known species of the S. "Gambarelloides" species group from the eastern Pacific: Synalpheus occidentalis Coutière, 1909, from Gulf of San José, Lower California, and Synalpheus mulegensis Ríos, 1992, from Bahía Concepción, Gulf of California, and can be differentiated from them by the poorly developed distal portion of pollex of the major cheliped, the armature of the distal segment of third maxilliped, and the number of acute teeth of exopodal uropod. A discriminative analysis dealing with other three species of Synalpheus from the western Atlantic, with distinctive pollex of major chela reduced, is presented. A dichotomous key was elaborated to identify the species of Synalpheus "Gambarelloides" species group from the eastern Pacific. The number of valid species described of Synalpheus from the eastern Pacific is increased to 23.