Pan-Arctic modelling of net ecosystem exchange of CO2 Journal Article

Authors: Shaver, G. R.; Rastetter, E. B.; Salmon, V.; Street, L. E.; van de Weg, M. J.; Rocha, A.; van Wijk, M. T.; Williams, M.
Article Title: Pan-Arctic modelling of net ecosystem exchange of CO2
Abstract: Net ecosystem exchange (NEE) of C varies greatly among Arctic ecosystems. Here, we show that approximately 75 per cent of this variation can be accounted for in a single regression model that predicts NEE as a function of leaf area index (LAI), air temperature and photosynthetically active radiation (PAR). The model was developed in concert with a survey of the light response of NEE in Arctic and subarctic tundras in Alaska, Greenland, Svalbard and Sweden. Model parametrizations based on data collected in one part of the Arctic can be used to predict NEE in other parts of the Arctic with accuracy similar to that of predictions based on data collected in the same site where NEE is predicted. The principal requirement for the dataset is that it should contain a sufficiently wide range of measurements of NEE at both high and low values of LAI, air temperature and PAR, to properly constrain the estimates of model parameters. Canopy N content can also be substituted for leaf area in predicting NEE, with equal or greater accuracy, but substitution of soil temperature for air temperature does not improve predictions. Overall, the results suggest a remarkable convergence in regulation of NEE in diverse ecosystem types throughout the Arctic.
Keywords: TEMPERATURE; carbon balance; TUNDRA; ALASKA; SENSITIVITY; CLIMATE-CHANGE; VEGETATION; NITROGEN; PRIMARY PRODUCTIVITY; LEAF-AREA INDEX; vascular plants; Arctic carbon cycling; net ecosystem exchange of carbon; carbon cycle modelling; pan-Arctic comparisons
Journal Title: Philosophical Transactions of the Royal Society of London Series B-Biological Sciences
Volume: 368
Issue: 1624
ISSN: 0962-8436
Publisher: Royal Society, The  
Date Published: 2013
Notes: PT: J; TC: 2; UT: WOS:000321565600007