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Showing 1 to 10 of 10 for “"15N tracer"”.
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The pathway of nitrogen assimilation in Datura stramonium L
… feeding levels has been investigated using 15N tracer experimentation, enzyme inhibitor studies and enzymological assays. Leaves were fed via their xylem stream with potassium nitrate at -1 -1 two concentration levels: 200 pg. N. ml and 25 JJ8 N. ml , prior to experimentation. Nitrate-15N …
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Fine root dynamics and resource uptake in a South Ecuadorian mountain rainforest as dependent on elevation
… N-Aufnahmefähigkeit von Feinwurzeln durch ein 15N-Tracer-Experiment zu erfassen und (3) mit Miniatur-Saftflusssystemen die Abhängigkeit des Wurzelsaftflusses von Umweltvariablen zu untersuchen sowie anatomische Charakteristika von Wurzelquerschnitten zu analysieren.Der Umsatz von Feinwurzeln (d …
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Tropical stony corals host diverse microbial nitrogen dynamics
… how they may impact coral success. Here we use 15N-tracer experiments to produce the first measurements of nitrate reduction, nitrite oxidation, and nitrous oxide (N2O) production in five species of reef-building corals in the Gardens of the Queen, Cuba. Nitrate reduction and nitrite oxidation …
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EFFECTS OF NITROGEN DEPOSITION ON BOREAL BOGS: A THREE YEAR NITROGEN FERTILIZATION AND TRACER EXPERIMENT
… A three-year N fertilization experiment with 15N double labeled 15NH415NO3 as a tracer was designed to study the effects of increasing N deposition on various N pools (including microbial communities, moss, roots, litter, and aboveground vascular plants) and how these N pools process and …
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Transformation and fate of nitrate in northern prairie wetlands
… transport rate to anaerobic zones;[superscript]15N tracer studies confirm denitrification to be the dominant fate of externally loaded nitrate in northern prairie wetlands, generally accounting for near 80% of the [superscript]15NO[subscript]3[superscript]- removed for the overlying water in …
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Flow and transport processes as affected by tillage management under monsoonal conditions in South Korea
… and flow dividers as well as Brilliant Blue FCF tracer experiments. The obtained datasets were used to calibrate the process-based models HYDRUS 2/3D and EROSION 3D in order to quantify drainage water fluxes, surface runoff and erosion rates of RTpm compared to ridge tillage without coverage (RT) …
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Budget and fluxes of nitrogen in mountainous agroecosystems in a summer monsoonal climate under intensive land use
… with polyethylene (PE) mulch by using 15N tracer. N leaching was simulated with Hydrus 2D. The comparison of 4 N fertilization levels (0, 150, 250 and 350 kg N ha-1) revealed that already 150 kg N ha-1 is sufficient to reach the maximal yield of radishes. Based on the low results of …
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Nitrogen isotope variation in the environment: Implications for interpretation
Natural abundance of 15N varies greatly and unpredictably within and between environments. The unpredictable nature of 15N limits the use of N isotope natural abundance (d15N) in tracing the flow and fate of N in environments. Recent investigations have, however, revealed consistent and repeatable …
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Phytoplankton's role in the biological pump during the growth season across the Atlantic Southern Ocean
… cycling in the summertime Weddell Sea, the 15N/14N of four groups sorted by flow cytometry (Synechococcus, picoeukaryotes, nanoeukaryotes, and cryptophytes) was measured. Phytoplankton growth fuelled by subsurface nitrate produces particulate organic N (PON) that is high in 15N/14N relative …