Nitrogen leaching from natural ecosystems under global change : A modelling study
(2017) In Earth System Dynamics 8(4). p.1121-1139- Abstract
To study global nitrogen (N) leaching from natural ecosystems under changing N deposition, climate, and atmospheric CO2, we performed a factorial model experiment for the period 1901-2006 with the N-enabled global terrestrial ecosystem model LPJ-GUESS (Lund-Potsdam-Jena General Ecosystem Simulator). In eight global simulations, we used either the true transient time series of N deposition, climate, and atmospheric CO2 as input or kept combinations of these drivers constant at initial values. The results show that N deposition is globally the strongest driver of simulated N leaching, individually causing an increase of 88% by 1997-2006 relative to pre-industrial conditions. Climate change led globally to a 31%increase in N... (More)
To study global nitrogen (N) leaching from natural ecosystems under changing N deposition, climate, and atmospheric CO2, we performed a factorial model experiment for the period 1901-2006 with the N-enabled global terrestrial ecosystem model LPJ-GUESS (Lund-Potsdam-Jena General Ecosystem Simulator). In eight global simulations, we used either the true transient time series of N deposition, climate, and atmospheric CO2 as input or kept combinations of these drivers constant at initial values. The results show that N deposition is globally the strongest driver of simulated N leaching, individually causing an increase of 88% by 1997-2006 relative to pre-industrial conditions. Climate change led globally to a 31%increase in N leaching, but the size and direction of change varied among global regions: Leaching generally increased in regions with high soil organic carbon storage and high initial N status, and decreased in regions with a positive trend in vegetation productivity or decreasing precipitation. Rising atmospheric CO2 generally caused decreased N leaching (33% globally), with strongest effects in regions with high productivity and N availability. All drivers combined resulted in a rise of N leaching by 73% with strongest increases in Europe, eastern North America and South-East Asia, where N deposition rates are highest. Decreases in N leaching were predicted for the Amazon and northern India. We further found that N loss by fire regionally is a large term in the N budget, associated with lower N leaching, particularly in semi-arid biomes. Predicted global N leaching from natural lands rose from 13.6 TgNyr-1 in 1901-1911 to 18.5 TgNyr-1 in 1997-2006, accounting for reductions of natural land cover. Ecosystem N status (quantified as the reduction of vegetation productivity due to N limitation) shows a similar positive temporal trend but large spatial variability. Interestingly, this variability is more strongly related to vegetation type than N input. Similarly, the relationship between N status and (relative) N leaching is highly variable due to confounding factors such as soil water fluxes, fire occurrence, and growing season length. Nevertheless, our results suggest that regions with very high N deposition rates are approaching a state of N saturation.
(Less)
- author
- Braakhekke, Maarten C. ; Rebel, Karin T. ; Dekker, Stefan C. ; Smith, Benjamin LU ; Beusen, Arthur S.W. and Wassen, Martin J.
- organization
- publishing date
- 2017-12-12
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Earth System Dynamics
- volume
- 8
- issue
- 4
- pages
- 19 pages
- publisher
- Copernicus GmbH
- external identifiers
-
- scopus:85038396971
- wos:000417850500001
- ISSN
- 2190-4979
- DOI
- 10.5194/esd-8-1121-2017
- language
- English
- LU publication?
- yes
- id
- cd111db4-5415-4532-9ba2-e014fbf358b5
- date added to LUP
- 2018-01-03 12:54:44
- date last changed
- 2025-02-04 04:03:57
@article{cd111db4-5415-4532-9ba2-e014fbf358b5, abstract = {{<p>To study global nitrogen (N) leaching from natural ecosystems under changing N deposition, climate, and atmospheric CO<sub>2</sub>, we performed a factorial model experiment for the period 1901-2006 with the N-enabled global terrestrial ecosystem model LPJ-GUESS (Lund-Potsdam-Jena General Ecosystem Simulator). In eight global simulations, we used either the true transient time series of N deposition, climate, and atmospheric CO2 as input or kept combinations of these drivers constant at initial values. The results show that N deposition is globally the strongest driver of simulated N leaching, individually causing an increase of 88% by 1997-2006 relative to pre-industrial conditions. Climate change led globally to a 31%increase in N leaching, but the size and direction of change varied among global regions: Leaching generally increased in regions with high soil organic carbon storage and high initial N status, and decreased in regions with a positive trend in vegetation productivity or decreasing precipitation. Rising atmospheric CO<sub>2</sub> generally caused decreased N leaching (33% globally), with strongest effects in regions with high productivity and N availability. All drivers combined resulted in a rise of N leaching by 73% with strongest increases in Europe, eastern North America and South-East Asia, where N deposition rates are highest. Decreases in N leaching were predicted for the Amazon and northern India. We further found that N loss by fire regionally is a large term in the N budget, associated with lower N leaching, particularly in semi-arid biomes. Predicted global N leaching from natural lands rose from 13.6 TgNyr<sup>-1</sup> in 1901-1911 to 18.5 TgNyr<sup>-1</sup> in 1997-2006, accounting for reductions of natural land cover. Ecosystem N status (quantified as the reduction of vegetation productivity due to N limitation) shows a similar positive temporal trend but large spatial variability. Interestingly, this variability is more strongly related to vegetation type than N input. Similarly, the relationship between N status and (relative) N leaching is highly variable due to confounding factors such as soil water fluxes, fire occurrence, and growing season length. Nevertheless, our results suggest that regions with very high N deposition rates are approaching a state of N saturation.</p>}}, author = {{Braakhekke, Maarten C. and Rebel, Karin T. and Dekker, Stefan C. and Smith, Benjamin and Beusen, Arthur S.W. and Wassen, Martin J.}}, issn = {{2190-4979}}, language = {{eng}}, month = {{12}}, number = {{4}}, pages = {{1121--1139}}, publisher = {{Copernicus GmbH}}, series = {{Earth System Dynamics}}, title = {{Nitrogen leaching from natural ecosystems under global change : A modelling study}}, url = {{http://dx.doi.org/10.5194/esd-8-1121-2017}}, doi = {{10.5194/esd-8-1121-2017}}, volume = {{8}}, year = {{2017}}, }