دورية أكاديمية

Dissolved organic carbon bioreactivity and DOC:DIN stoichiometry control ammonium uptake in an intermittent Mediterranean stream

التفاصيل البيبلوغرافية
العنوان: Dissolved organic carbon bioreactivity and DOC:DIN stoichiometry control ammonium uptake in an intermittent Mediterranean stream
المؤلفون: Peñarroya, Xavier, Lupon, Anna, Triadó-Margarit, Xavier, Martí, Eugènia, Ledesma, José L. J., Ribot, Miquel, Soler, Montserrat, Casamayor, Emilio O., Bernal, Susana
المصدر: Freshwater Biology, 68 (9), 1572–1587 ; ISSN: 0046-5070, 1365-2427
بيانات النشر: John Wiley and Sons
سنة النشر: 2023
المجموعة: KITopen (Karlsruhe Institute of Technologie)
مصطلحات موضوعية: dissolved organic carbon availability, heterotrophic activity, in-stream nitrogen uptake, stream biofilms, stream metabolism, ddc:910, Geography & travel, info:eu-repo/classification/ddc/910
الوصف: 1. Heterotrophic organisms in streams use dissolved organic carbon (DOC) and dissolved inorganic nitrogen (DIN) from the water column to meet their growth and energy requirements. However, the role of DOC availability in driving DIN uptake in headwater streams is still poorly understood. In this study, we focus on how DOC:DIN stoichiometry and DOC bioreactivity control ammonium (NH$_4$$^+$) uptake and heterotrophic aerobic respiration, and how this influence varies among seasons in a forested Mediterranean headwater stream. 2. We estimated in-stream NH$_4$$^+$ uptake rates seasonally by conducting whole-reach constant-rate additions of NH$_4$$^+$ with and without amendments of either lignin (recalcitrant DOC) or acetate (labile DOC). During each addition, we characterised microbial community composition by molecular analyses, stream metabolism with the single-station method, and heterotrophic aerobic respiration by adding a metabolic tracer (resazurin). 3. The stream was heterotrophic (net ecosystem production <0) regardless of the season, with a microbial community mostly composed of heterotrophic bacteria. In-stream NH$_4$$^+$ uptake rates were not related to either background NH$_4$$^+$ or DOC concentrations. Instead, these rates increased with increasing the molar ratio of NH$_4$$^+$ to nitrate (NO$_3$$^−$) (NH$_4$$^+$:NO$_3$$^−$) and DOC to DIN (DOC:DIN).Whole-reach heterotrophic aerobic respiration rates showed the same relationship against stoichiometric ratios as NH$_4$$^+$ uptake rates. Furthermore, in-stream NH$_4$$^+$ uptake rates were from 5% to >800% higher during the co-additions of acetate than when adding NH$_4$$^+$ either alone or with lignin. 4. Our results indicate that in-stream NH$_4$$^+$ uptake was largely controlled by heterotrophic bacteria, and that the stoichiometric balance between organic resources and nutrients was key to explaining the variability of in-stream NH$_4$$^+$ uptake and heterotrophic aerobic respiration. Moreover, the observed increase in NH$_4$$^+$ uptake during ...
نوع الوثيقة: article in journal/newspaper
وصف الملف: application/pdf
اللغة: English
العلاقة: info:eu-repo/semantics/altIdentifier/wos/001035312900001; info:eu-repo/semantics/altIdentifier/issn/0046-5070; info:eu-repo/semantics/altIdentifier/issn/1365-2427; https://publikationen.bibliothek.kit.edu/1000161415Test; https://publikationen.bibliothek.kit.edu/1000161415/151171720Test; https://doi.org/10.5445/IR/1000161415Test
DOI: 10.5445/IR/1000161415
الإتاحة: https://doi.org/10.5445/IR/1000161415Test
https://doi.org/10.1111/fwb.14152Test
https://publikationen.bibliothek.kit.edu/1000161415Test
https://publikationen.bibliothek.kit.edu/1000161415/151171720Test
حقوق: https://creativecommons.org/licenses/by-nc/4.0/deed.deTest ; info:eu-repo/semantics/openAccess
رقم الانضمام: edsbas.14A95453
قاعدة البيانات: BASE