Volcanic activity impacts ecosystems sometimes with multiple, complex and long-lasting consequences, including volcanic tephra (airborne material) causing widespread disruptions. We study the effects of tephra deposition around two tropical lakes of Ecuador using a multi-proxy analysis of lake sediment archives spanning the last 2000 years. We present the dynamics of terrestrial vegetation (pollen), aquatic macroinvertebrate fauna (chironomids) and organic matter (stable isotopes) in: (i) a high elevation, stream-connected, open alpine grassland (Andean páramo) and (ii) a mid-elevation, stream-isolated, pre-montane forest. Páramo vegetation showed a slight increase in herbs and quick recovery after the tephra deposition; however, the aquatic community suffered a regime shift not reversed today c. 1500 years after the event. In the pre-montane location, the canopy opened up following tephra deposition, and it took c. 150 years to return to pre-impact levels. At the forested site, no major changes in the aquatic fauna were observed related to the tephra deposition. We hypothesise that the forest acted as a protective barrier preventing a large fallout of ash into the aquatic system. Forest not only acted as a buffer for ash falling into the water from the air, but also prevented landslides of tephra by enhancing soil stability, contrary to what was observed in the open system. We demonstrate the protective ecosystem service that forests play in sustaining ecological resilience and water quality facing natural (volcanic) disturbance. The ongoing deforestation of tropical regions therefore might increase the vulnerability of aquatic ecosystems, threatening the water quality for ecosystems and human populations.

火山活动有时会对生态系统造成多重，复杂和持久的影响，其中包括造成广泛破坏的火山特非拉（空气传播的物质）​​。我们通过对过去2000年的湖泊沉积物档案进行多代理分析，研究了厄瓜多尔两个热带湖泊周围的特发拉沉积的影响。我们在以下方面介绍了陆地植被（花粉），水生大型无脊椎动物动物群（动物纲）和有机物（稳定同位素）的动态：（i）高海拔，溪流相连，开放的高山草原（Andeanpáramo）和（ii）中游海拔，溪流隔离，山前森林。特发拉沉积后，Páramo植被显示草药略有增加，并迅速恢复；但是，水生社区的政权转变今天没有逆转。事件发生后1500年。在山地前的位置，天蓬在沉积特非拉之后打开，并花了c左右。150年恢复到撞击前的水平。在森林地带，未观察到与特非拉沉积有关的水生动物群的重大变化。我们假设森林起到了保护屏障的作用，可以防止大量的灰烬散落到水生系统中。与开放系统中观察到的相反，森林不仅起到了将灰烬从空中掉入水中的缓冲作用，而且还通过增强土壤的稳定性防止了特非拉的滑坡。我们展示了森林在面对自然（火山）干扰时在维持生态弹性和水质方面发挥的保护性生态系统服务。因此，热带地区的持续森林砍伐可能会增加水生生态系统的脆弱性，