Lake Superior coastal forests have warmed 0.6–1.7°C, shifting climate envelopes ~240 km northwards. This has produced an adaptation lag between local trees and climates, which may have cascading effects on hydrologic regimes. However, the link between tree climate adaptation and tree hydrological function has not previously been studied despite potential ramifications for watershed management.
To fill this gap, we will study the ecophysiology and hydrological features of two sites in a single Lake Superior watershed. These sites were logged in 2010-2012 and then planted in 2013 with two-year-old seedlings of two tree species that are predicted to thrive in future climates. In addition, a local and southern seed source was planted for each species. In 2020-2021, we will investigate climatological suitability and phenotypic differentiation amongst these four types of 10-year-old trees. To this end, we will measure survivorship, phenology, specific leaf area, and individual tree-level evapotranspiration (ET) using a specialized portable rapid ET chamber. Hydrometerological data including rainfall, temperature, volumetric water content, and streamflow will also be collected.
Using these pieces of information, we will model the impact of each tree type on watershed hydrology and investigate the hydrologic outcomes of different ratios of forest cover. This work will have enabled us to link biodiversity shifts due to climate change to their potential impacts on forest watershed hydrology.
Speaker(s)
Erin Bergen, Julie Etterson, Salli Dymond, University of Minnesota Duluth