Declining tree growth resilience mediates subsequent forest mortality in the US Mountain West

Abstract

Rising global temperatures due to human greenhouse gas emissions pose a threat to Earth's forests. Notably, increasing temperature has been linked to higher frequency and intensity of drought-induced forest background mortality and die-off (Allen et al., 2015;Breshears et al., 2009;Williams et al., 2012). Largescale forest die-off is of particular concern due to its dramatic disruption of forest function, with large consequences on biodiversity (Betts et al., 2017;Feng et al., 2021), ecosystem goods and services, and forests' prominent role in the global carbon cycle (Anderegg, Trugman, Badgley, Anderson, et al., 2020). The western US has experienced extensive drought-and insect-induced tree mortality over the past decades, associated with strong drying trends in the area (

Tree species explain only half of explained spatial variability in plant water sensitivity

“…Yet they can be performed for many species, facilitated by efforts to aggregate species occurrence records like the Global Biodiversity Information Facility (GBIF, Robertson et al., 2014). Additionally, our findings point to the utility of considering not just a single study site when analyzing a particular species, but studying the same species' behavior across an expansive network of study sites (e.g., Cabon et al., 2023; Lockwood et al., 2023; Novick, Jo, et al., 2022), so that the roles of climate, soil, and topography are at least partially integrated.…”

“…Because plant hydraulic traits vary significantly by species (Bartlett et al., 2016; Skelton et al., 2015), many studies of plant drought and water stress response analyze vegetation behavior as a function of species (e.g., Brzostek et al., 2014; Cabon et al., 2023; Serra‐Maluquer et al., 2022). However, the focus on species‐by‐species differences in studies of plant water stress neglects the fact that plant hydraulic traits may exhibit significant intra‐specific variability (González de Andrés et al., 2021; Kannenberg et al., 2022; Lu et al., 2022), including through adaptation to local climate (Depardieu et al., 2020; Pritzkow et al., 2020).…”

Contrasting patterns of water use efficiency and annual radial growth among European beech forests along the Italian peninsula

“…Several studies have demonstrated that long-term rises in instability and reduced growth predispose European beech to elevated mortality risks under future climate-induced stress conditions (Gillner et al ., 2013; DeSoto et al ., 2020; Cabon et al ., 2023). The loss of stability in our study sites emphasizes the need for continuous monitoring and proactive management of beech forests, particularly in regions where climate change is projected to increase the frequency and severity of droughts.…”

“…Furthermore, our analysis of EWS reveals the loss of resilience after an extreme event, as notably observed at the TRE site. In the context of climate model projection, the increase in the frequency and severity of droughts, the ability to detect earlier tipping points of critical slowdowns in declining systems, and the potential for recovery to the current state or an alternative state remains uncertain (Cabon et al ., 2023).…”