Abstract Detail

Ecology

Bergen, Erin [1], Etterson, Julie R. [2], Dymond, Salli F. [3].

Climate change and assisted migration: linking phenologic compatibility and watershed impacts of Quercus ecotypes.

Lake Superior coastal forests have warmed 0.6–1.7°C over the last century, and climatic conditions that were once local to this region have shifted away, bringing climate envelopes ~240 km northwards. This extreme and rapid climate shift has resulted in an adaptation lag between local trees and local climates, with cascading effects on local hydrologic regimes. A mismatch between climate and tree adaptations may increase tree mortality, reduce vigor, and reduce forest resilience to destructive weather events. To bolster forest health and restoration success, the climate compatibility of restoration tree stock must be considered. Condition-specific adaptations found in locally-adapted and genetically-distinct subpopulations, ecotypes, present opportunities for choosing restoration materials that are ideal for current and future climate change. Ecotypes demonstrably differ in phenological traits and potentially in hydrological traits as well. The ecohydrology of ecotypes is a facet of climate suitability that is largely unexplored yet has implications for forested watershed health in response to forest restoration.
We are investigating the ecophysiology and hydrological features of two sites in a single Lake Superior watershed in Minnesota. These sites were logged in 2010-2012, burned, and then planted in 2013 with two-year-old seedlings of two oak species: Q. rubra and Q. macrocarpa. In addition, a local (northern) and southern ecotype was planted for each species. In 2020-2021, our study investigates climatological suitability and differentiation in our four ecotypes by measuring and comparing survivorship, phenology, and transpiration. Preliminary results of 2020 data show statistically significant phenologic differentiation among the ecotypes. Survival, budburst, first full leaf, full canopy, and senescence stages all differ by at least population or species, if not both. In several cases, there is more differentiation between populations within a species than across species, especially for Q. rubra. Alongside this work, we will characterize stream discharge and use all field data to construct a hydrologic mass-balance model of the watershed with variable forest cover compositions to infer the impacts of each tree species and ecotype on streamflow. This work will enable us to link biodiversity shifts due to climate change to their potential impacts on forested watershed hydrology.

1 - University of Minnesota Duluth, 1035 Kirby Drive, 207 Swenson Science Building, Duluth, MN, 55812, United States
2 - University Of Minnesota Duluth, 207 Swenson Science Building, 1110 Kirby Drive, 6770 Haugen Lane, 1035 Kirby Drive, Duluth, MN, 55803, United States
3 - University of Minnesota Duluth, Earth & Environmental Sciences Department, 1114 Kirby Drive, 230 Heller Hall, Duluth, MN, 55812, United States

Keywords:
climate niche
climate change
Climate and vegetation changes
phenology
population differentiation
Differentiation
watershed hydrology
restoration
common garden
ecotypes.

Presentation Type: Oral Paper
Session: ECO3, Ecology: Climate Change
Location: /
Date: Tuesday, July 20th, 2021
Time: 4:00 PM(EDT)
Number: ECO3005
Abstract ID:953
Candidate for Awards:None