NGEE Arctic
Next-Generation Ecosystem Experiments
Advancing the predictive power of Earth system models through understanding
of the structure and function of Arctic terrestrial ecosystems
Field Measurements of Photosynthetic Biochemistry Provide Improved Representation of Gas-Exchange in ESMs
Field Measurements of Photosynthetic Biochemistry Provide Improved Representation of Gas-Exchange in ESMs
September 1st, 2017
Study highlights the poor representation of Arctic photosynthesis in TBMs, and provides the critical data necessary to improve our ability to project the response of the Arctic to global environmental change.
The Objective:
- Measure photosynthetic CO2 response curves and leaf nitrogen (N) content in species representing the dominant vascular plant functional types found on the coastal tundra near Barrow, Alaska.
New Science:
- Photosynthesis, specifically the carboxylation rate and electron transport on forbs, grasses, sedges, and shrubs, were made throughout five years.
- Traits could be assigned to plant functional types used in land surface models (e.g. ALM).
The Impact:
- Provides the first dataset on photosynthetic capacity for understanding physiology of cold-adapted species in the Arctic.
- Photosynthesis is inadequately described due to a low leaf nitrogen content and the fraction of that nitrogen partitioned to Rubisco.
- Productivity is underestimated in this globally important and climatically-sensitive biome.
Carboxylation capacity measured on Arctic vegetation at NGEE Arctic field sites outside Barrow, AK.