Forest floor carbon dioxide fluxes within an upland-peatland complex in the Western Boreal Plain, Canada

✍ Scribed by Danielle S. Solondz; Richard M. Petrone; Kevin J. Devito

• Publisher: John Wiley and Sons
• Year: 2008
• Tongue: English
• Weight: 550 KB
• Volume: 1
• Category: Article
• ISSN: 1936-0584
• DOI: 10.1002/eco.30

✦ Synopsis

This study examined the midday (10 : 00 to 16 : 00) growing season (April to October) surface cover CO 2 relationships with different canopy closures in a forested upland-peatland-pond complex in the Western Boreal Plain (WBP), north-central Alberta, Canada. Large differences were observed among the forest floors of landscape units with different canopy covers with respect to midday total respiration [ R tot D vegetation respiration R veg C soil respiration (R soil )] and gross ecosystem production (GEP), and the seasonal pattern of GEP and R tot . Highest rates of R tot followed the general progression of riparian > upland > open peatland > covered peatland, with high R soil contributions. Strong correlations were observed between C : N, soil temperature, moisture and R tot . Photosynthetic active radiation (PAR) controlled the GEP, which was highest in the open and covered peatland. GEP and R tot were highest in the middle of the growing season when soil and air temperatures were warmest; in addition R veg contributed more to R tot during this time. However, R soil dominated the flux.

This study demonstrated that controlling environmental factors on CO 2 exchange cannot necessarily be extrapolated among land cover units within a sub-humid region, such as Canada's WBP. In addition, forest floors of different land cover units, and microtopography should be taken into account when discussing understory contributions to CO 2 exchange.