Quantifying the contribution of mass flow to nitrogen acquisition by an individual plant root
© 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.
| Veröffentlicht in: | The New phytologist. - 1979. - 218(2018), 1 vom: 11. Apr., Seite 119-130 |
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| Format: | Online-Aufsatz |
| Sprache: | English |
| Veröffentlicht: |
2018
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| Zugriff auf das übergeordnete Werk: | The New phytologist |
| Schlagworte: | Journal Article Research Support, Non-U.S. Gov't diffusion mass flow nitrogen (N) immobilization nitrogen uptake model rhizosphere processes root-microbe competition root-nitrogen uptake soil-nitrogen transport mehr... |
| Zusammenfassung: | © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust. The classic model of nitrogen (N) flux into roots is as a Michaelis-Menten (MM) function of soil-N concentration at root surfaces. Furthermore, soil-N transport processes that determine soil-N concentration at root surfaces are seen as a bottleneck for plant nutrition. Yet, neither the MM relationship nor soil-N transport mechanisms are represented in current terrestrial biosphere models. Processes governing N supply to roots - diffusion, mass flow, N immobilization by soil microbes - are incorporated in a model of root-N uptake. We highlight a seldom considered interaction between these processes: nutrient traverses the rhizosphere more quickly in the presence of mass flow, reducing the probability of its immobilization before reaching the root surface. Root-N uptake is sensitive to the rate of mass flow for widely spaced roots with high N uptake capacity, but not for closely spaced roots or roots with low uptake capacity. The results point to a benefit of root switching from high- to low-affinity N transport systems in the presence of mass flow. Simulations indicate a strong impact of soil water uptake on N delivery to widely spaced roots through transpirationally driven mass flow. Furthermore, a given rate of N uptake per unit soil volume may be achieved by lower root biomass in the presence of mass flow |
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| Beschreibung: | Date Completed 27.09.2019 Date Revised 30.09.2020 published: Print-Electronic CommentIn: New Phytol. 2018 Apr;218(1):8-11. doi: 10.1111/nph.15022. - PMID 29488283 Citation Status MEDLINE |
| ISSN: | 1469-8137 |
| DOI: | 10.1111/nph.14927 |