El Nino x forest resilience

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The widespread and rapid logging of tropical forests may mean they are unable to withstand climate shocks such as El Niño events. Logging slashes the abundance of invertebrates like ants and earthworms, but vertebrates can take up their roles in the ecosystem. Invertebrates perform essential functions for the smooth running of the ecosystems in tropical forests. For example, creatures such as termites and millipedes help dead leaves decompose and release their nutrients back into the soil, and carnivorous ants and spiders act as predators of herbivorous invertebrates that would otherwise munch through all the foliage.Nearly a half of all tropical rainforests worldwide have been logged, and this often causes heavy changes to the number and type of invertebrates, with many species being lost from the ecosystem. But when invertebrate diversity declines, their vital functions can be carried out by other members of the ecosystem, including vertebrates including rodents, birds and bats. Because of this, rainforest ecosystems have a remarkable resilience to change. However, although the ecosystem can continue to function with vertebrates taking more of a leading role, the situation leaves rainforests vulnerable: the forest will keep maintaining itself, but it will be much more susceptible to further change. Relying on vertebrates is probably a bad tactic - they are less diverse and vulnerable to new challenges.One such new challenge is the drought that accompanies El Niño events. There is already evidence that El Niño events can disrupt the resilience of ecosystem processes to logging disturbance. For example, the number of seedlings germinate and establish in logged forest during an El Niño year is just one-sixth of the number that establish in primary forest during the same year. What's more, those seedlings then die almost twice as fast in a logged forest during El Niño than they do in primary forest.This project will examine the resilience of tropical forest ecosystem processes to an El Niño event, asking specifically whether El Niño reduces the resilience of ecosystem processes to logging disturbance that otherwise keeps those forests functioning between El Niño events. I will do this by comparing historical data collected in both primary and logged forests with new data that will be collected during the 2016 El Niño event. My goal is to generate a broad picture of the interactive impacts of El Niño and logging on the forest ecosystem as a whole, for which I will necessarily sacrifice detailed understanding of any one ecosystem process.Instead, I will be looking at a very broad range of data types and measurements of how the forest works and what species are doing the jobs. The data will record the rate at which 15 ecosystem processes operate in primary and logged forest habitats, encompassing metrics of tree dynamics, interactions across plant and animal communities and nutrient recycling processes. These data will be compared to records on the abundance and biomass of 26 functional groups nested within seven plant and animal communities, covering all major trophic groups including early and late successional tree species, and vertebrate and invertebrate herbivores, predators, scavengers and omnivores.