The field season is beginning to wrap up, and as such one team in particular has been working hastily to collect their multitude of data before heading home. These researchers focus on willow ecology, led in the field by Columbia University graduate student Ian Shuman. Ian’s Ph.D. project is centered around willow growth, which he originally hypothesized was determined by physiology but is now finding that genetics and environmental factors play a much larger role.
Ian, accompanied by URA Timna Nevo and REU Stella Otstot, have spent the summer estimating Salix alexensis and Salix pulchra photosynthetic capacity by varying the carbon dioxide levels that the leaves are exposed to using a LiCOR-6800. They have also been measuring the environmental conditions surrounding each individual, as well as their annual primary (upwards) and secondary (outwards) growth per year, then comparing it to growth data going as far back as 2011. This information will be compared between the two species and across the study’s Arctic latitudinal gradient to assess how each species is responding to the Earth’s changing climate. The data collected in the field will soon be processed by Research Technician Mary Rutter and REU Jenna Kent at the University of Connecticut (UConn) to include willow individual genetics and landscape genetics for a more comprehensive look into this study. All the data collected from these experiments will eventually be combined into an Integral Projection Model being built by PI Cory Merow at UConn to better explore how the correlation of willow physiology, growth, and environmental conditions influence the demography of willow populations across the Arctic.
A Salix alexensis leaf is analyzed in the LiCOR-6800’s stable chamber while still attached to the host plant at Galbraith Creek. Photo: Stellaria Otstot.
Grad student Ian Shuman and REU Stella Otstot pack up the willows after measuring their physiology and cutting them in the field. The willows are then taken back to the lab at Toolik Field Station for growth analyses. Photo: Timna Nevo.
