Canopy nitrogen and tree carbon uptake
Canopy-applied 15N is recovered aboveground about three times more than soil-applied N.
Source
Does canopy nitrogen uptake enhance carbon sequestration by trees?
Study at a glance
- Design
- Animal / in-vitro — 15N tracer mesocosm comparing canopy vs soil nitrogen targeting in Sitka spruce
- N
- Potted Sitka spruce mesocosms; mean aboveground biomass 370 g/tree — exact tree N not primary in stored text
- Population
- Potted Sitka spruce trees
- Outcome
- Aboveground and wood recovery of canopy-applied vs soil-applied 15N
Structured fields used in claim comparison tables when every cited study has a complete layer.
What they did
Traced 15N applied to Sitka spruce canopies versus soil in potted mesocosms from February 2013 to March 2014, then harvested trees.
What they found
Canopy N uptake recovered about three times more tracer aboveground and four times more in wood than soil-targeted deposition; needle δ15N reached about 120‰ versus 38‰.
The limits
What it doesn't show
Does not measure whole-forest C stocks or prove that canopy uptake changes landscape-scale carbon sequestration.
Key terms
- Canopy nitrogen uptake (CNU)
- Foliage taking up deposited nitrogen before it reaches soil.
- N deposition (NDEP)
- Atmospheric nitrogen falling onto ecosystems.
- 15N tracer
- Heavy nitrogen isotope used to follow N movement.
- ΔC/ΔN
- Extra carbon stored per unit extra nitrogen.
- Mesocosm
- Potted experimental ecosystem.
- Soil nitrogen uptake (SNU)
- N added to soil rather than foliage.
Flashcards
Research intelligence for this paper
See its role on concept claims, tensions it is part of, placement history, and related discoveries.
Quiz yourself
Aboveground 15N from canopy vs soil N was about:
Common questions
Study trees?
Sitka spruce saplings.
Aboveground 15N vs soil?
About three times more from canopy application.
Wood 15N?
About four times higher from CNU.
Mean aboveground biomass?
370 ± 119 g per tree.
More on Carbon cycle