Assessing Impacts of Plant Stoichiometric Traits on Terrestrial Ecosystem Carbon Accumulation Using the E3SM Land Model
Abstract Carbon (C) enters into the terrestrial ecosystems via photosynthesis and cycles through the system together with other essential nutrients (i.e., nitrogen [N] and phosphorus [P]). Such a strong coupling of C, N, and P leads to the theoretical prediction that limited nutrient availability wi...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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American Geophysical Union (AGU)
2020-04-01
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| Series: | Journal of Advances in Modeling Earth Systems |
| Subjects: | |
| Online Access: | https://doi.org/10.1029/2019MS001841 |
| _version_ | 1797662355801243648 |
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| author | Qing Zhu William J. Riley Colleen M. Iversen Jens Kattge |
| author_facet | Qing Zhu William J. Riley Colleen M. Iversen Jens Kattge |
| author_sort | Qing Zhu |
| collection | DOAJ |
| description | Abstract Carbon (C) enters into the terrestrial ecosystems via photosynthesis and cycles through the system together with other essential nutrients (i.e., nitrogen [N] and phosphorus [P]). Such a strong coupling of C, N, and P leads to the theoretical prediction that limited nutrient availability will limit photosynthesis rate, plant growth, and future terrestrial C dynamics. However, the lack of reliable information about plant tissue stoichiometric constraints remains a challenge for quantifying nutrient limitations on projected global C cycling. In this study, we harmonized observed plant tissue C:N:P stoichiometry from more than 6,000 plant species with the commonly used plant functional type framework in global land models. Using observed C:N:P stoichiometry and the flexibility of these ratios as emergent plant traits, we show that observationally constrained fixed plant stoichiometry does not improve model estimates of present‐day C dynamics compared with unconstrained stoichiometry. However, adopting stoichiometric flexibility significantly improves model predictions of C fluxes and stocks. The 21st century simulations with RCP8.5 CO2 concentrations show that stoichiometric flexibility, rather than baseline stoichiometric ratios, is the dominant controller of plant productivity and ecosystem C accumulation in modeled responses to CO2 fertilization. The enhanced nutrient limitations and plant P use efficiency mainly explain this result. This study is consistent with the previous consensus that nutrient availability will limit xfuture land carbon sequestration but challenges the idea that imbalances between C and nutrient supplies and fixed stoichiometry limit future land C sinks. We show here that it is necessary to represent nutrient stoichiometric flexibility in models to accurately project future terrestrial ecosystem carbon sequestration. |
| first_indexed | 2024-03-11T18:58:02Z |
| format | Article |
| id | doaj.art-ec390e32b22843eb81beb8b158ab6c2c |
| institution | Directory Open Access Journal |
| issn | 1942-2466 |
| language | English |
| last_indexed | 2024-03-11T18:58:02Z |
| publishDate | 2020-04-01 |
| publisher | American Geophysical Union (AGU) |
| record_format | Article |
| series | Journal of Advances in Modeling Earth Systems |
| spelling | doaj.art-ec390e32b22843eb81beb8b158ab6c2c2023-10-10T14:11:54ZengAmerican Geophysical Union (AGU)Journal of Advances in Modeling Earth Systems1942-24662020-04-01124n/an/a10.1029/2019MS001841Assessing Impacts of Plant Stoichiometric Traits on Terrestrial Ecosystem Carbon Accumulation Using the E3SM Land ModelQing Zhu0William J. Riley1Colleen M. Iversen2Jens Kattge3Climate Sciences Department, Climate and Ecosystem Sciences Division Lawrence Berkeley National Laboratory Berkeley CA USAClimate Sciences Department, Climate and Ecosystem Sciences Division Lawrence Berkeley National Laboratory Berkeley CA USAClimate Change Science Institute and Environmental Sciences Division Oak Ridge National Laboratory Oak Ridge TN USAMax Planck Institute for Biogeochemistry Jena GermanyAbstract Carbon (C) enters into the terrestrial ecosystems via photosynthesis and cycles through the system together with other essential nutrients (i.e., nitrogen [N] and phosphorus [P]). Such a strong coupling of C, N, and P leads to the theoretical prediction that limited nutrient availability will limit photosynthesis rate, plant growth, and future terrestrial C dynamics. However, the lack of reliable information about plant tissue stoichiometric constraints remains a challenge for quantifying nutrient limitations on projected global C cycling. In this study, we harmonized observed plant tissue C:N:P stoichiometry from more than 6,000 plant species with the commonly used plant functional type framework in global land models. Using observed C:N:P stoichiometry and the flexibility of these ratios as emergent plant traits, we show that observationally constrained fixed plant stoichiometry does not improve model estimates of present‐day C dynamics compared with unconstrained stoichiometry. However, adopting stoichiometric flexibility significantly improves model predictions of C fluxes and stocks. The 21st century simulations with RCP8.5 CO2 concentrations show that stoichiometric flexibility, rather than baseline stoichiometric ratios, is the dominant controller of plant productivity and ecosystem C accumulation in modeled responses to CO2 fertilization. The enhanced nutrient limitations and plant P use efficiency mainly explain this result. This study is consistent with the previous consensus that nutrient availability will limit xfuture land carbon sequestration but challenges the idea that imbalances between C and nutrient supplies and fixed stoichiometry limit future land C sinks. We show here that it is necessary to represent nutrient stoichiometric flexibility in models to accurately project future terrestrial ecosystem carbon sequestration.https://doi.org/10.1029/2019MS001841carbon‐nutrient interactionsearth system land model (E3SM)future ecosystem carbon accumulation |
| spellingShingle | Qing Zhu William J. Riley Colleen M. Iversen Jens Kattge Assessing Impacts of Plant Stoichiometric Traits on Terrestrial Ecosystem Carbon Accumulation Using the E3SM Land Model Journal of Advances in Modeling Earth Systems carbon‐nutrient interactions earth system land model (E3SM) future ecosystem carbon accumulation |
| title | Assessing Impacts of Plant Stoichiometric Traits on Terrestrial Ecosystem Carbon Accumulation Using the E3SM Land Model |
| title_full | Assessing Impacts of Plant Stoichiometric Traits on Terrestrial Ecosystem Carbon Accumulation Using the E3SM Land Model |
| title_fullStr | Assessing Impacts of Plant Stoichiometric Traits on Terrestrial Ecosystem Carbon Accumulation Using the E3SM Land Model |
| title_full_unstemmed | Assessing Impacts of Plant Stoichiometric Traits on Terrestrial Ecosystem Carbon Accumulation Using the E3SM Land Model |
| title_short | Assessing Impacts of Plant Stoichiometric Traits on Terrestrial Ecosystem Carbon Accumulation Using the E3SM Land Model |
| title_sort | assessing impacts of plant stoichiometric traits on terrestrial ecosystem carbon accumulation using the e3sm land model |
| topic | carbon‐nutrient interactions earth system land model (E3SM) future ecosystem carbon accumulation |
| url | https://doi.org/10.1029/2019MS001841 |
| work_keys_str_mv | AT qingzhu assessingimpactsofplantstoichiometrictraitsonterrestrialecosystemcarbonaccumulationusingthee3smlandmodel AT williamjriley assessingimpactsofplantstoichiometrictraitsonterrestrialecosystemcarbonaccumulationusingthee3smlandmodel AT colleenmiversen assessingimpactsofplantstoichiometrictraitsonterrestrialecosystemcarbonaccumulationusingthee3smlandmodel AT jenskattge assessingimpactsofplantstoichiometrictraitsonterrestrialecosystemcarbonaccumulationusingthee3smlandmodel |