A Comparison of Carbon Dioxide Net Production in Three Flooded Uplands (FLUDEX, 1999–2002) and a Flooded Wetland (ELARP, 1991–2002) Using a Dynamic Model

Abstract

We used a dynamic model to estimate the net carbon dioxide production (NCP) of three experimentally flooded upland areas (FLUDEX) over a period of 4 years and NCP from a flooded wetland (ELARP) over 12 years (2 year pre-flooding, 10 years post-flooding). The 3 flooded upland areas had been chosen to have differing amounts of carbon stored in soils and vegetation. Estimates of NCP ranged from 33–55 mmole·m⁻²·d⁻¹ in the first year and decreased steadily to 13–30 mmole·m⁻²·d⁻¹ in the fourth year. The NCP from the reservoir with the lowest carbon stock was always lowest, the other two were similar. The NCP estimated for the wetland rose from 45 mmole·m⁻²·d⁻¹ in the first year of flooding to 178 mmole·m⁻²·d⁻¹ in the years 7–9. A decrease to 126 mmole·m⁻²·d⁻¹ was seen in the last year. Overall the model did a good job of simulating the measured results and provided a consistent methodology for comparison of NCP. In this boreal forest area of northwest Ontario flooding of wetland area results in much higher NCP and over a much greater duration than upland flooding.