Groundwater flow patterns and geochemistry were studied in the Mer Bleue bog, near Ottawa, Ontario, Canada. Groundwater flow patterns alternated between recharge, i.e. head gradients producing flow from the surface of the peatland to the deeper peat, and discharge, i.e. head gradients indicating flow from the deeper peat towards the surface of the peatland, during… More
Our objective was to evaluate the relative importance of gradients in light intensity and the isotopic composition of atmospheric CO2 for variation in leaf carbon isotope ratios within a Pinus resinosa forest. In addition, we measured photosynthetic gas exchange and leaf carbon isotope ratios on four understory species (Dryopteris carthusiana, Epipactus helleborine, Hieracium floribundum, Rhamnus… More
We analyzed the relationship between net ecosystem exchange of carbon dioxide (NEE) and irradiance (as photosynthetic photon flux density or PPFD), using published and unpublished data that have been collected during midgrowing season for carbon balance studies at seven peatlands in North America and Europe. NEE measurements included both eddy-correlation tower and clear, static chamber… More
Northern peatlands contain enormous quantities of organic carbon within a few meters of the atmosphere and play a significant role in the planetary carbon balance. We have developed a new, process-oriented model of the contemporary carbon balance of northern peatlands, the Peatland Carbon Simulator (PCARS). Components of PCARS are (1) vascular and nonvascular plant photosynthesis… More
Recent and long-term accumulation rates of carbon (C), using 210Pb- and 14C-dating, were examined in 23 ombrotrophic peatlands in eastern Canada, where average 1990–1996 atmospheric wet nitrogen (N) deposition ranged from 0.3 to 0.8 g N m−2 yr−1. The average recent rate of C accumulation (RERCA) over the past 150 years was 73 ± 17… More
The AmeriFlux Tech Team has completed another successful site visit season. This year, eight (8) site visits were completed. Here are a few images from the site visits. The Tech Team is planning for the 2017 site visit season. If you would like to learn more about site visits and what to expect, please see our… More