Drought Sensitivity and Resilience of Oak–Hickory Stands in the Eastern United States

oleh: Tsun Fung Au, Justin T. Maxwell

Format: Article
Diterbitkan: MDPI AG 2022-02-01

Deskripsi

Forest composition in the eastern United States (US) has been shifting from an oak–hickory to maple–beech assemblage, but whether there are species-specific differences within these oak–hickory stands in their responses and recovery from drought remains unclear. Here, we examined drought responses and resilience derived from radial growth of 485 co-occurring <i>Carya ovata</i> and <i>Quercus alba</i> individual trees at 15 forests in the eastern US. Water availability over the growing season (May to August) of the current year controls growth variability of both <i>C. ovata</i> and <i>Q. alba</i>. Drought that occurred in June caused the greatest growth reduction for both species while interspecific differences inof drought-induced growth reduction was found in July, where <i>Q. alba</i> experienced stronger reduction than <i>C. ovata</i>. Both species are resilient to early growing season drought, but late growing season drought caused larger drought legacy effects for <i>Q. alba</i>. The increasing drought frequency and intensity will have a more prominent impact in oak–hickory stands in the eastern US. The species composition of a forest along with species-specific responses and recovery is likely to be a critical control on forest productivity and species abundance.