Elevational shifts in foliar-soil δ15 N in the Hengduan Mountains and different potential mechanisms
© 2022 John Wiley & Sons Ltd.
| Veröffentlicht in: | Global change biology. - 1999. - 28(2022), 18 vom: 14. Sept., Seite 5480-5491 |
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| Weitere Verfasser: | , , |
| Format: | Online-Aufsatz |
| Sprache: | English |
| Veröffentlicht: |
2022
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| Zugriff auf das übergeordnete Werk: | Global change biology |
| Schlagworte: | Journal Article altitude forestland microbial assimilation nitrogen cycle stable isotope Nitrogen Isotopes Soil Nitrogen N762921K75 |
| Zusammenfassung: | © 2022 John Wiley & Sons Ltd. The natural abundance of stable nitrogen isotopes (δ15 N) provides insights into the N dynamics of terrestrial ecosystems, the determination of which is considered an effective approach for gaining a better understanding ecosystem N cycling. However, there is currently little information available regarding the patterns and mechanisms underlying the variation in foliar-soil δ15 N among mountain ecosystems. In this study, we examined the determinants of foliar-soil δ15 N in association with N transportation rates along an elevational gradient in the Hengduan Mountains. Despite the relatively high levels of available N produced from high N fixation and mineralization, we detected the lowest levels of foliar δ15 N at 3500 m a.s.l., reflecting the stronger vegetation N limitation at medium high elevations. The enhanced vegetation N limitation was driven by the combined effects of higher microbial immobilization and inherent plant dynamic (the shifts of δ15 N in vegetation preference, including vegetation community) with changing climate along the elevational gradient. Unexpectedly, we established that soil δ15 N was characterized by an undulating rise and uncoupled correlation with foliar δ15 N with increasing elevation, thereby indicating that litter input might not be a prominent driver of soil δ15 N. Conversely, soil nitrification and denitrification were found to make a more pronounced contribution to the pattern of soil δ15 N along the elevational gradient. Collectively, our results serve to highlight the importance of microbial immobilization in soil N dynamics and provide novel insights that will contribute to enhancing our understanding of N cycling as indicated by foliar-soil δ15 N along elevational gradients |
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| Beschreibung: | Date Completed 16.08.2022 Date Revised 26.09.2022 published: Print-Electronic Citation Status MEDLINE |
| ISSN: | 1365-2486 |
| DOI: | 10.1111/gcb.16306 |