Hokkaido University Collection of Scholarly and Academic Papers >
Field Science Center for Northern Biosphere >
Peer-reviewed Journal Articles, etc >
Vertical Changes in the Flux of Atmospheric Nitrate From a Forest Canopy to the Surface Soil Based on Delta O-17 Values
Title: | Vertical Changes in the Flux of Atmospheric Nitrate From a Forest Canopy to the Surface Soil Based on Delta O-17 Values |
Authors: | Inoue, Takahiro Browse this author | Nakagawa, Fumiko Browse this author | Shibata, Hideaki Browse this author →KAKEN DB | Tsunogai, Urumu Browse this author →KAKEN DB |
Keywords: | atmospheric nitrate | canopy retention | coniferous‐broadleaved mixed forest | delta‐O‐17 | nitrogen deposition |
Issue Date: | Apr-2021 |
Publisher: | American Geophysical Union |
Journal Title: | Journal of geophysical research biogeosciences |
Volume: | 126 |
Issue: | 4 |
Start Page: | e2020JG005876 |
Publisher DOI: | 10.1029/2020JG005876 |
Abstract: | To better understand the factors that control N retention and N export in forested watersheds, it is necessary to understand the relationships among atmospheric nitrogen (N) deposition, internal N cycling within plant-soil systems, and N leaching. The relative contributions of atmospheric nitrate (NO3atm-) and remineralized nitrate produced by microbial nitrification to total nitrate (NO3-) in stream water have been investigated in many studies. However, the dynamics of these two types of NO3- from the forest canopy to the soil are not well understood. Therefore, we determined the changes in the NO3- flux and the O-17 excess (Delta O-17) of NO3-, a robust tracer of NO3atm-, from bulk deposition to the soil water beneath oak and spruce trees as well as dwarf bamboo-dominated canopy gaps in a natural coniferous-broadleaved mixed forest in northern Japan. The Delta O-17 values in NO3- dramatically decreased after passing through the forest floor, indicating that the dominant source of NO3- leaching is nitrification in the forest floor. In contrast, a large decrease in NO3atm- flux was observed between bulk deposition and throughfall, especially for oak and spruce, suggesting that the forest canopy is an important sink for deposited NO3atm-. The retention of NO3atm- by the canopy was higher for oak (86.3 +/- 10.1%) and spruce (87.7 +/- 8.8%) than for Sasa in the canopy gap (49.9 +/- 26.6%). Our study demonstrated that the Delta O-17 value of NO3- is a promising tool for quantifying the atmospheric nitrate dynamics in complex forest N cycling. |
Type: | article |
URI: | http://hdl.handle.net/2115/83153 |
Appears in Collections: | 北方生物圏フィールド科学センター (Field Science Center for Northern Biosphere) > 雑誌発表論文等 (Peer-reviewed Journal Articles, etc)
|
Submitter: 井上 貴央
|