1. C[O.sub.2] flux from Acer saccharum logs: sources of variation and the influence of silvicultural treatments
- Author
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Read, Zoe, Fraver, Shawn, D'Amato, Anthony W., Evans, Daniel M., Evans, Kevin, Lutz, David A., and Woodall, Christopher W.
- Subjects
Carbon cycle (Biogeochemistry) -- Environmental aspects ,Woody plants -- Environmental aspects ,Arboriculture -- Environmental aspects ,Earth sciences - Abstract
Several aspects of the forest carbon cycle have not been examined in detail, including sources of variation in carbon dioxide (C[O.sub.2]) emissions from coarse woody material (CWM). To address this knowledge gap, we examined C[O.sub.2] emissions from Acer saccharum Marshall logs within four harvesting treatments, using closed chambers fitted to the logs. We found that C[O.sub.2] emissions were highest for logs in small (31.8 [+ or -] 20.4 [micro]molC[O.sub.2][m.sup.- 3][s.sup.-1]) and large gaps (29.6 [+ or -] 24.4 [micro]molC[O.sub.2][m.sup.-3][s.sup.-1]) compared to those in control (13.9 [+ or -] 8.3 [micro]molC[O.sub.2][m.sup.-3][s.sup.-1]) and thinned matrix (13.6 [+ or -] 8.0 [micro]molC[O.sub.2][m.sup.-3] [s.sup.-1]) treatments. C[O.sub.2] flux rates did not differ between gap sizes, but they increased with temperature, which was higher in the small gap treatment. In addition, two individual logs fitted with multiple closed chambers revealed significant within-log variability in C[O.sub.2] emissions. On a subset of logs repeatedly sampled throughout the day, we found that log surface temperature generally peaked at midday and was positively correlated with C[O.sub.2] emissions, although this relationship was weak in one log. This study provides insight into sources of variation in C[O.sub.2] emissions from CWM while improving our understanding of the forest carbon cycle. Key words: carbon dioxide, carbon flux, forest carbon cycle, woody material, wood decomposition, Introduction Forests are important contributors to the global carbon cycle, both as a sink of carbon dioxide (C[O.sub.2]) through photosynthesis as well as an emitter of C[O.sub.2] as these carbon [...]
- Published
- 2023
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