Drought timing and local climate determine the sensitivity of eastern temperate forests to drought
- Department of Biology Indiana University Bloomington IN USA, Centre d’Étude de la Forêt Université du Québec à Montréal Montréal QC Canada
- Department of Geography Indiana University Bloomington IN USA
- Centre d’Étude de la Forêt Université du Québec à Montréal Montréal QC Canada
- Harvard Forest Harvard University Petersham MA USA
- Direction de la Recherche Forestière Ministère des Forêts, de la Faune et des Parcs du Québec Québec City QC Canada
- Ouranos Climate Change Consortium Montreal QC Canada
- Direction de la Recherche Forestière Ministère des Forêts, de la Faune et des Parcs du Québec Québec City QC Canada, Ouranos Climate Change Consortium Montreal QC Canada
- Department of Biology, Chemistry and Geography Université du Québec à Rimouski Rimouski QC Canada
- Department of Forest and Natural Resources Management SUNY‐ESF Syracuse NY USA
- Lamont‐Doherty Earth Observatory Columbia University Palisades NY USA
- Geological, Environmental, and Marine Sciences Rider University Lawrenceville NJ USA
- School of Forest Resources University of Maine Orono ME USA
- Department of Geography Université de Montréal Montréal QC Canada
- Vermont Department of Forests, Parks &, Recreation Essex Junction VT USA
- Rubenstein School of the Environment and Natural Resources University of Vermont Burlington VT USA
- Department of Geography University of Alabama Tuscaloosa AL USA
- Department of Biogeochemical Processes Max Planck Institute for Biogeochemistry Jena Germany
- Department of Ecosystem Science and Management Penn State College of Agricultural Sciences State College PA USA
- Department of Biology Ball State University Muncie IN USA
- Stockholm University Stockholm Sweden
- Department of Geography University of Vermont Burlington VT USA
- The Morton Arboretum Lisle IL USA
- Department of Biology Indiana University Bloomington IN USA
Projected changes in temperature and drought regime are likely to reduce carbon (C) storage in forests, thereby amplifying rates of climate change. While such reductions are often presumed to be greatest in semi‐arid forests that experience widespread tree mortality, the consequences of drought may also be important in temperate mesic forests of Eastern North America ( ENA ) if tree growth is significantly curtailed by drought. Investigations of the environmental conditions that determine drought sensitivity are critically needed to accurately predict ecosystem feedbacks to climate change. We matched site factors with the growth responses to drought of 10,753 trees across mesic forests of ENA , representing 24 species and 346 stands, to determine the broad‐scale drivers of drought sensitivity for the dominant trees in ENA . Here we show that two factors—the timing of drought, and the atmospheric demand for water (i.e., local potential evapotranspiration; PET )—are stronger drivers of drought sensitivity than soil and stand characteristics. Drought‐induced reductions in tree growth were greatest when the droughts occurred during early‐season peaks in radial growth, especially for trees growing in the warmest, driest regions (i.e., highest PET ). Further, mean species trait values (rooting depth and ψ 50 ) were poor predictors of drought sensitivity, as intraspecific variation in sensitivity was equal to or greater than interspecific variation in 17 of 24 species. From a general circulation model ensemble, we find that future increases in early‐season PET may exacerbate these effects, and potentially offset gains in C uptake and storage in ENA owing to other global change factors.
- Sponsoring Organization:
- USDOE
- OSTI ID:
- 1429514
- Journal Information:
- Global Change Biology, Journal Name: Global Change Biology Journal Issue: 6 Vol. 24; ISSN 1354-1013
- Publisher:
- Wiley-BlackwellCopyright Statement
- Country of Publication:
- United Kingdom
- Language:
- English