More than just a scaffold, xylem conduits deliver the water necessary for reproductive and metabolic processes, importantly including turgor maintenance—and with it, the form and function of more than 300,000 plant species globally. Across these many species, the anatomy, physiology, and structural roles of xylem is highly varied. Xylem’s importance extends far beyond plants, as vegetated terrestrial biomes are hosts to most of Earth's biodiversity, and plant transpiration accounts for more than 80% of all terrestrial evaporation. Xylem’s function underpins innumerable, complex processes. Yet, its vital role in supporting global biodiversity, and fluxes of both water and carbon, is tenuous, and the impairment and eventual failure of xylem can result in devastating consequences for plants and plant dependent life. Here, we present the xylem functional traits database (XFT), an interactive web application hosting the world’s largest set of observations for xylem vulnerability, with over 4,500 unique observations. Geographically, our database contains observations on six continents. Taxonomically, the XFT covers Pteridophytes, Gymnosperms, and Angiosperms, with observations of xylem vulnerability for ∼1,570 species, 723 genera, and 166 families. Climatically, xylem vulnerability has been measured in plants growing across gradients of 30°C of mean annual temperature, and 4 meters of mean annual rainfall. Yet, major biases and gaps across space, climate, and growth forms limit our understanding of xylem vulnerability. We outline critical next steps to further understanding the global vulnerability of plant xylem.
|Publication status||Print publication - 19 Sept 2022|