environmental Controls on Arctic plant gas Exchange
The Arctic is warming at rapid, unprecedented rates, causing cascading ecological and environmental changes that threaten to destabilize the vast amounts of carbon stored in the vegetation and soils of the tundra. These changes include increased ambient temperatures, expanded woody shrub cover and deeper thaw depth, which collectively alter the soil nutrient status in the historically nitrogen and phosphorus limited environment.
My dissertation research, conducted at Toolik Lake, Alaska, characterized how foliar carbon cycling in dominant tundra species is affected and controlled by warming-mediated environmental change. Using the long-term global change experiment established by Gus Shaver and Terry Chapin at the Arctic LTER field site, we measured photosynthesis, respiration, and associated leaf traits grown under elevated temperatures and nutrient addition. Other projects characterized how foliar gas exchange varies through the Arctic growing season and through a woody shrub canopy. |
Related publications
Heskel MA, Greaves HE*, Turnbull MH, O'Sullivan OS, Shaver GR, Griffin KL, Atkin OK. Thermal acclimation of shoot respiration in an Arctic woody plant species subjected to 22 years of warming and altered nutrient supply. Global Change Biology, 20 (8): 2618:2630. DOI: 10.1111/gcb.12544
Heskel MA, Bitterman D, Atkin OK, Turnbull MH, Griffin KL. Respiration responds to both long-term warming and short-term temperature variability in Arctic plants. Functional Plant Biology 41(3): 287-300. DOI: 10.1071/FP13137
Heskel M, Greaves HE, Kornfeld A, Atkin OK, Turnbull MH, Shaver, GR, Griffin KL (2013) Differential physiological responses to environmental change promote woody shrub expansion. Ecology and Evolution 3 (5): 1149-1162. DOI: 10.1002/ece3.525
Kornfeld A, Heskel MA, Atkin OK, Gough L, Griffin KL, Horton TW, Turnbull MH (2013) Respiratory flexibility and efficiency are affected by simulated global change in Arctic plant. New Phytologist 197 (4): 1161-1172. DOI:10.1111/nph.12083
Heskel MA, Anderson OR, Atkin OK, Turnbull MH, Griffin KL (2012) Leaf- and cell-level carbon cycling responses to a nitrogen and phosphorus gradient in two Arctic tundra species. American Journal of Botany. 99, 1702-1714 DOI: 10.3732/ajb.1200251e et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation.
Heskel MA, Bitterman D, Atkin OK, Turnbull MH, Griffin KL. Respiration responds to both long-term warming and short-term temperature variability in Arctic plants. Functional Plant Biology 41(3): 287-300. DOI: 10.1071/FP13137
Heskel M, Greaves HE, Kornfeld A, Atkin OK, Turnbull MH, Shaver, GR, Griffin KL (2013) Differential physiological responses to environmental change promote woody shrub expansion. Ecology and Evolution 3 (5): 1149-1162. DOI: 10.1002/ece3.525
Kornfeld A, Heskel MA, Atkin OK, Gough L, Griffin KL, Horton TW, Turnbull MH (2013) Respiratory flexibility and efficiency are affected by simulated global change in Arctic plant. New Phytologist 197 (4): 1161-1172. DOI:10.1111/nph.12083
Heskel MA, Anderson OR, Atkin OK, Turnbull MH, Griffin KL (2012) Leaf- and cell-level carbon cycling responses to a nitrogen and phosphorus gradient in two Arctic tundra species. American Journal of Botany. 99, 1702-1714 DOI: 10.3732/ajb.1200251e et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation.