Assessing the Impacts of Environmental Change on Plant Form and Function
1) Do climate and biotic interactions influence the growth rates of juvenile?
Janneke HilleRisLambers, Leander D. L. Anderegg, Ian Breckheimer, Kathleen M. Burns, Ailene K. Ettinger, Jerry F. Franklin, James A. Freund, Kevin R. Ford and Steve J. Kroiss. 2016, "Implications for climate change for turnover in forest composition". 2016 Northwest Science 89(3): 201-218
2) How do climate and biotic interactions influence leaf growth? Does leaf growth mediate organismal function across environmental heterogeneity?
2014 - 2015
(right) Presented at the 2015 Undergraduate Research Symposium at the University of Washington, Plant Biology 2015 (American Society of Plant Biologists) and ESA 2015 (Ecological Society of America) If interested in a more legible/clear file feel free to email me.
3) What strategies (specifically: trait coordination, mechanistic physiology) do leaves of juvenile trees employ when acclimating to climatic and biotic stressors?
2015 - 2016
To investigate the leaf morphological, anatomical, and functional changes associated with environmental change stressors, I conducted a greenhouse experiment and subjected aspen saplings to low-water or low-light availability.
For details on this work check out:
(below) Plant physiological measurements require the necessary equipment. Osmometer on the left measures osmolality or osmolute potential, and a pH meter in the center for measuring pH.
(above) Top: 1) Withholding water from seedlings leads to leaf senescence at active meristems. Water after ~month is absorbed and previously dormant buds become active. Incredible plant resilience to drought!
2 & 3) Low-watered plants produce leaves with less area and increased density (thereby elevated mass) compared to well-watered plants that produce leaves (above, right) with greater area and reduced relative density (thereby reduced mass per area). Interestingly, these leaves were indifferent in cross sectional thickness, suggesting adequate acclimation to high light (under low-water availability) These leaves are the same age (give or take ~2 days of differential emergence -> ~2 months old)
Middle: 4) Measuring photosynthetic accumulation via LiCor 6400 at several different light quantities to construct photosynthesis light curves.
5) P. tremuloides leaf cross sections made via Vibratome.
Bottom: 6) Leaf expansion rate at the shoot apical meristem was monitored throughout all treatments.
7) Measuring osmotic potential via freezing point osmometer. Water potential and osmotic potential values can be used to calculate turgor pressure values.