Abstract
Soil carbon (C) pools and plant community composition are regulated by nitrogen (N) and phosphorus (P) availability. Atmospheric N deposition impacts ecosystem C storage, but the direction of response varies between systems. Phosphorus limitation may constrain C storage response to N, hence P application to increase plant productivity and thus C sequestration has been suggested. We revisited a 23-yr-old field experiment where N and P had been applied to upland heath, a widespread habitat supporting large soil C stocks. At 10 yr after the last nutrient application we quantified long-term changes in vegetation composition and in soil and vegetation C and P stocks. Nitrogen addition, particularly when combined with P, strongly influenced vegetation composition, favouring grasses over Calluna vulgaris, and led to a reduction in vegetation C stocks. However, soil C stocks did not respond to nutrient treatments. We found 40% of the added P had accumulated in the soil. This study showed persistent effects of N and N + P on vegetation composition, whereas effects of P alone were small and showed recovery. We found no indication that P application could mitigate the effects of N on vegetation or increase C sequestration in this system.
Original language | English |
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Pages (from-to) | 226-237 |
Number of pages | 12 |
Journal | New Phytologist |
Volume | 228 |
Issue number | 1 |
Early online date | 24 Jun 2020 |
DOIs | |
Publication status | Published - Oct 2020 |
Bibliographical note
Open Access via the Wiley Jisc Agreement.Funding Information
Scottish Natural Heritage
Royal Society of Edinburgh Fellowship
Scottish Government Rural and Environment Science and Analytical Services Division (RESAS)
N8 AgriFood
Keywords
- long-term
- nitrogen deposition
- nutrient cycling
- upland heath
- soil
- vegetation
- long term
- DEPOSITION INCREASES
- NUTRIENT LIMITATION
- VASCULAR PLANTS
- RESPONSES
- COMMUNITY STRUCTURE
- MICROBIAL BIOMASS
- SPHAGNUM
- LITTER
- LONG-TERM NITROGEN
- ATMOSPHERIC NITROGEN