The role of stoichiometric flexibility in modelling forest ecosystem responses to nitrogen fertilization

© 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

Bibliographische Detailangaben
Veröffentlicht in:The New phytologist. - 1979. - 208(2015), 4 vom: 27. Dez., Seite 1042-55
1. Verfasser: Meyerholt, Johannes (VerfasserIn)
Weitere Verfasser: Zaehle, Sönke
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2015
Zugriff auf das übergeordnete Werk:The New phytologist
Schlagworte:Journal Article Research Support, Non-U.S. Gov't carbon-nitrogen cycle coupling ecosystem modelling fertilization forest carbon balance nitrogen cycle plant stoichiometry Fertilizers Soil mehr... Carbon 7440-44-0 Nitrogen N762921K75
Beschreibung
Zusammenfassung:© 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.
The response of the forest carbon (C) balance to changes in nitrogen (N) deposition is uncertain, partly owing to diverging representations of N cycle processes in dynamic global vegetation models (DGVMs). Here, we examined how different assumptions about the degree of flexibility of the ecosystem's C : N ratios contribute to this uncertainty, and which of these assumptions best correspond to the available data. We applied these assumptions within the framework of a DGVM and compared the results to responses in net primary productivity (NPP), leaf N concentration, and ecosystem N partitioning, observed at 22 forest N fertilization experiments. Employing flexible ecosystem pool C : N ratios generally resulted in the most convincing model-data agreement with respect to production and foliar N responses. An intermediate degree of stoichiometric flexibility in vegetation, where wood C : N ratio changes were decoupled from leaf and root C : N ratio changes, led to consistent simulation of production and N cycle responses to N addition. Assuming fixed C : N ratios or scaling leaf N concentration changes to other tissues, commonly assumed by DGVMs, was not supported by reported data. Between the tested assumptions, the simulated changes in ecosystem C storage relative to changes in C assimilation varied by up to 20%
Beschreibung:Date Completed 06.09.2016
Date Revised 30.09.2020
published: Print-Electronic
Citation Status MEDLINE
ISSN:1469-8137
DOI:10.1111/nph.13547