Academic Journal
Gradients of Anthropogenic Nutrient Enrichment Alter N Composition and DOM Stoichiometry in Freshwater Ecosystems
| العنوان: | Gradients of Anthropogenic Nutrient Enrichment Alter N Composition and DOM Stoichiometry in Freshwater Ecosystems |
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| المؤلفون: | Wymore, Adam S., Johnes, Penny J., Bernal, Susana, Brookshire, E. N. Jack, Fazekas, Hannah M., Helton, A. M., Argerich, A., Barnes, Rebecca T., Coble, A. A., Dodds, W. K., Haq, Shahan, Johnson, S. L., Jones, J. B., Kaushal, S. S., Kortelainen, Pirkko, López-Lloreda, Carla, Rodríguez-Cardona, Bianca M., Spencer, Robert G. M., Sullivan, Pamela L., Yates, Christopher A., McDowell, W. H. |
| بيانات النشر: | American Geophysical Union |
| سنة النشر: | 2021 |
| المجموعة: | Digital.CSIC (Consejo Superior de Investigaciones Científicas / Spanish National Research Council) |
| الوصف: | Este artículo contiene 11 páginas, 3 figuras, 1 tabla. ; A comprehensive cross-biome assessment of major nitrogen (N) species that includes dissolved organic N (DON) is central to understanding interactions between inorganic nutrients and organic matter in running waters. Here, we synthesize stream water N chemistry across biomes and find that the composition of the dissolved N pool shifts from highly heterogeneous to primarily comprised of inorganic N, in tandem with dissolved organic matter (DOM) becoming more N-rich, in response to nutrient enrichment from human disturbances. We identify two critical thresholds of total dissolved N (TDN) concentrations where the proportions of organic and inorganic N shift. With low TDN concentrations (0–1.3 mg/L N), the dominant form of N is highly variable, and DON ranges from 0% to 100% of TDN. At TDN concentrations above 2.8 mg/L, inorganic N dominates the N pool and DON rarely exceeds 25% of TDN. This transition to inorganic N dominance coincides with a shift in the stoichiometry of the DOM pool, where DOM becomes progressively enriched in N and DON concentrations are less tightly associated with concentrations of dissolved organic carbon (DOC). This shift in DOM stoichiometry (defined as DOC:DON ratios) suggests that fundamental changes in the biogeochemical cycles of C and N in freshwater ecosystems are occurring across the globe as human activity alters inorganic N and DOM sources and availability. Alterations to DOM stoichiometry are likely to have important implications for both the fate of DOM and its role as a source of N as it is transported downstream to the coastal ocean. ; Acknowledgments This work was conducted as a part of the Stream Elemental Cycling Synthesis Group funded by the National Science Foundation (NSF) under grant DEB#1545288, through the Long-Term Ecological Research Network Office (LNO), National Center for Ecological Analysis and Synthesis (NCEAS), University of California-Santa Barbara. s. Partial support for ASW during data synthesis and ... |
| نوع الوثيقة: | article in journal/newspaper |
| اللغة: | English |
| تدمد: | 0886-6236 1944-9224 |
| Relation: | Publisher's Version; https://doi.org/10.1029/2021GB006953; Sí; Global Biogeochemical Cycles 35 : e2021GB006953 (2021); http://hdl.handle.net/10261/248550 |
| الاتاحة: | http://hdl.handle.net/10261/248550 |
| Rights: | open |
| رقم الانضمام: | edsbas.D538A554 |
| قاعدة البيانات: | BASE |
| تدمد: | 08866236 19449224 |
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