KIT | KIT-Bibliothek | Impressum | Datenschutz

Sources and Sinks of N in Ecosystem Solutions Along the Water Path Through a Tropical Montane Forest in Ecuador Assessed With δ15 N Values of Total Dissolved Nitrogen

Alvarez, Pablo 1; Velescu, Andre 1; Pierick, Kerstin; Homeier, Juergen; Wilcke, Wolfgang ORCID iD icon 1
1 Institut für Geographie und Geoökologie (IFGG), Karlsruher Institut für Technologie (KIT)

Abstract:

The globally increasing reactive N richness affects even remote ecosystems such as the tropical montane forests in Ecuador. We tested whether the δ15N values of total dissolved N (TDN), measured directly in solution with a TOC-IRMS, can be used to help elucidate N sources and sinks along the water path and thus might be suitable for ecosystem monitoring. From 2013 to 2016, the δ15N values of TDN in bulk deposition showed the most pronounced temporal variation of all ecosystem solutions (δ15N values: 1.9–5.9‰). In throughfall (TF), TDN was on average 15N-depleted (−1.8 ± s.d. 0.4‰) relative to rainfall (3.4 ± 0.9‰), resulting from net retention of isotopically heavy N, mainly as NH4 +. Simultaneously, N-isotopically light NO3 -N and dissolved organic nitrogen (DON) with a δ15N value between NO3 -N and NH4 +-N were leached from the canopy (leaves: −3.5 ± 0.5‰). The increasing δ15N values in the order, TF < stemflow (SF, 0.1 ± 0.6‰)< litter leachate (LL, 1.3 ± 0.7‰) concurred with an increasing DON contribution to TDN reflecting the δ15N value of the organic layer (1.9 ± 0.9‰). ... mehr

Zugehörige Institution(en) am KIT Institut für Geographie und Geoökologie (IFGG)
Publikationstyp Zeitschriftenaufsatz
Publikationsmonat/-jahr 10.2024
Sprache Englisch
Identifikator ISSN: 2169-8953, 2169-8961
KITopen-ID: 1000175051
Erschienen in Journal of Geophysical Research: Biogeosciences
Verlag John Wiley and Sons
Band 129
Heft 10
Seiten e2024JG008043
Vorab online veröffentlicht am 25.09.2024
Schlagwörter nitrogen stable isotope ratio, dissolved organic matter, dissolved organic nitrogen, total dissolved nitrogen, ecosystem solution
Nachgewiesen in OpenAlex
Web of Science
Scopus
Dimensions

Verlagsausgabe §
DOI: 10.5445/IR/1000175051
Veröffentlicht am 11.10.2024
Seitenaufrufe: 52
seit 11.10.2024
Downloads: 34
seit 14.10.2024
Cover der Publikation
KIT – Die Forschungsuniversität in der Helmholtz-Gemeinschaft
KITopen Landing Page