Dataset Information

Seasonal dynamics of stem N₂O exchange follow the physiological activity of boreal trees.

ABSTRACT: The role of trees in the nitrous oxide (N₂O) balance of boreal forests has been neglected despite evidence suggesting their substantial contribution. We measured seasonal changes in N₂O fluxes from soil and stems of boreal trees in Finland, showing clear seasonality in stem N₂O flux following tree physiological activity, particularly processes of CO₂ uptake and release. Stem N₂O emissions peak during the vegetation season, decrease rapidly in October, and remain low but significant to the annual totals during winter dormancy. Trees growing on dry soils even turn to consumption of N₂O from the atmosphere during dormancy, thereby reducing their overall N₂O emissions. At an annual scale, pine, spruce and birch are net N₂O sources, with spruce being the strongest emitter. Boreal trees thus markedly contribute to the seasonal dynamics of ecosystem N₂O exchange, and their species-specific contribution should be included into forest emission inventories.

SUBMITTER: Machacova K

PROVIDER: S-EPMC6825224 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature

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Seasonal dynamics of stem N2O exchange follow the physiological activity of boreal trees.

Machacova Katerina K Vainio Elisa E Urban Otmar O Pihlatie Mari M

Nature communications 20191101 1

The role of trees in the nitrous oxide (N2O) balance of boreal forests has been neglected despite evidence suggesting their substantial contribution. We measured seasonal changes in N2O fluxes from soil and stems of boreal trees in Finland, showing clear seasonality in stem N2O flux following tree physiological activity, particularly processes of CO2 uptake and release. Stem N2O emissions peak during the vegetation season, decrease rapidly i ...[more]

PMID: 31676776

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Dataset Information

Seasonal dynamics of stem N₂O exchange follow the physiological activity of boreal trees.

Publications

Seasonal dynamics of stem N<sub>2</sub>O exchange follow the physiological activity of boreal trees.

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