El Nino x forest resilience

热带森林的广泛和快速砍伐可能意味着它们无法抵御厄尔尼诺现象等气候冲击。伐木减少了蚂蚁和蚯蚓等无脊椎动物的数量，但脊椎动物可以在生态系统中扮演自己的角色。无脊椎动物对热带森林生态系统的平稳运行起着至关重要的作用。例如，白蚁和千足虫等生物帮助枯叶分解并将其养分释放回土壤中，而食肉蚂蚁和蜘蛛充当草食性无脊椎动物的捕食者，否则它们将吞噬所有的树叶。世界上近一半的热带雨林被砍伐，这往往导致无脊椎动物的数量和类型发生重大变化，许多物种从生态系统中消失。但当无脊椎动物的多样性下降时，它们的重要功能可以由生态系统的其他成员来执行，包括啮齿动物、鸟类和蝙蝠等脊椎动物。正因为如此，热带雨林生态系统对变化具有非凡的适应能力。然而，尽管生态系统可以在脊椎动物发挥更大主导作用的情况下继续发挥作用，但这种情况让热带雨林变得脆弱：森林将继续自我维持，但它将更容易受到进一步变化的影响。依赖脊椎动物可能是一种糟糕的策略--它们的多样性减少，容易受到新挑战的影响。其中一个新挑战是伴随厄尔尼诺现象而来的干旱。已经有证据表明，厄尔尼诺事件可能扰乱生态系统进程对伐木干扰的适应能力。例如，在厄尔尼诺现象期间，伐木林中萌发和建立的苗木数量仅为同年在原始林中建立的数量的六分之一。更重要的是，在厄尔尼诺期间，这些幼苗在被砍伐的森林中死亡的速度几乎是在原始森林中的两倍。该项目将研究热带森林生态系统过程对厄尔尼诺事件的适应能力，特别是询问厄尔尼诺现象是否会降低生态系统过程对伐木干扰的适应能力，否则在厄尔尼诺事件期间，热带森林将保持其功能。我将通过比较在原始森林和伐木森林收集的历史数据与将在2016年厄尔尼诺事件期间收集的新数据来做到这一点。我的目标是对厄尔尼诺现象和伐木对整个森林生态系统的交互影响产生广泛的影响，为此，我必须牺牲对任何一个生态系统过程的详细了解。相反，我将研究非常广泛的数据类型和测量，了解森林是如何运作的，以及哪些物种在发挥作用。这些数据将记录15个生态系统过程在原始森林生境和伐木森林生境中的运行速度，包括树木动态、动植物群落之间的相互作用以及养分循环过程的指标。这些数据将与嵌套在七个动植物群落中的26个功能类群的丰度和生物量记录进行比较，涵盖所有主要的营养类群，包括演替早期和后期的树种，以及脊椎动物和无脊椎动物、草食动物、捕食者、食腐动物和杂食动物。

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.