Global change and desertification drivers, such as climate change and increased fire frequency, make drylands more prone to abrupt shifts that can lead to the emergence of degraded states unable to provide key ecosystem services and to sustain life. However, we still lack an in-depth understanding of the prevalence and triggers of these shifts, and of the identity of those ecosystem attributes and services that are most affected, across global drylands. These uncertainties arise largely from the absence of global monitoring efforts and experiments investigating temporal changes in biodiversity and associated ecosystem services. Furthermore, the lack of a systematic evaluation of the ecological impacts of restoration actions, such as tree planting, hampers our capacity to assess their usefulness to prevent abrupt ecosystem shifts and to combat climate change and desertification. BIOSHIFT will combine global-scale experimentation and temporal field surveys with state-of-the-art Earth observation, mathematical modelling, -omics approaches, and statistical analyses to tackle these key knowledge gaps. Specifically, I will: i) determine the prevalence, drivers and consequences of abrupt ecosystem shifts in drylands, ii) assess whether in situ temporal changes in dryland biodiversity and ecosystem services exhibit threshold-like responses along global aridity gradients, and iii) conduct the first systematic field assessment of the ecological impacts of tree plantations and their capacity to prevent abrupt ecosystem shifts in drylands worldwide. By doing so, BIOSHIFT will make a major leap forward in our understanding of abrupt ecosystem shifts and provide unprecedent insights on how to monitor and manage them. This project will also provide the ecological underpinning to high profile international initiatives aimed at tackling biodiversity losses, mitigating global change and desertification impacts, and restoring degraded ecosystems across global drylands.
