Titelangaben
Buchmann, Nina ; Schulze, Ernst-Detlef ; Gebauer, Gerhard:
15N-ammonium and 15N-nitrate uptake of a 15-year-old Picea abies plantation.
In: Oecologia.
Bd. 102
(1995)
Heft 3
.
- S. 361-370.
ISSN 1432-1939
DOI: https://doi.org/10.1007/BF00329803
Abstract
Throughfall nitrogen of a 15-year-old Picea abies (L.) Karst. (Norway spruce) stand in the Fichtelgebirge, Germany, was labeled with either 15N-ammonium or 15N-nitrate and uptake of these two tracers was followed during two successive growing seasons (1991 and 1992). 15N-labeling (62 mg 15N m-2 under conditions of 1.5 g N m-2 atmospheric nitrogen deposition) did not increase N concentrations in plant tissues. The 15N recovery within the entire stand (including soils) was 94% +/- 6% of the applied 15N- ammonium tracer and 100% +/- 6% of the applied 15N- nitrate tracer during the Ist year of investigation. This decreased to 80% +/- 24% and 83% +/- 20%, respectively, during the 2nd year. After 11 days, the 15N tracer was detectable in 1-year-old spruce needles and leaves of understory species. After 1 month, tracer was detectable in needle litter fall. At the end of the first growing season, more than 50% of the 15N taken up by spruce was assimilated in needles, and more than 20% in twigs. The relative distribution of recovered tracer of both 15N-ammonium and 15N-nitrate was similar within the different foliage age classes (recent to ii-year-old) and other compartments of the trees. 15N enrichment generally decreased with increasing tissue age. Roots accounted for up to 20% of the recovered 15N in spruce; no enrichment could be detected in stem wood. Although 15N-ammonium and 15N-nitrate were applied in the same molar quantities ((NH4+)-15N:(NO3-)-15N =1:1), the tracers were diluted differently in the inorganic soil N pools ((NH4+)-15N/NH4+: (NO3-)-15N/NO3- = 1:9). Therefore the measured 15N amounts retained by the vegetation do not represent the actual fluxes of ammonium and nitrate in the soil solution. Use of the molar ammonium-to-nitrate ratio of 9:1 in the soil water extract to estimate 15N uptake from inorganic N pools resulted in a 2-4 times higher ammonium than nitrate uptake by P. abies.
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Publikationsform: | Artikel in einer Zeitschrift |
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Begutachteter Beitrag: | Ja |
Zusätzliche Informationen: | BAYCEER6789 |
Institutionen der Universität: | Fakultäten > Fakultät für Biologie, Chemie und Geowissenschaften > Fachgruppe Biologie > Lehrstuhl Pflanzenökologie Fakultäten > Fakultät für Biologie, Chemie und Geowissenschaften > Fachgruppe Biologie Forschungseinrichtungen > Forschungszentren > Bayreuther Zentrum für Ökologie und Umweltforschung - BayCEER Fakultäten Fakultäten > Fakultät für Biologie, Chemie und Geowissenschaften Forschungseinrichtungen Forschungseinrichtungen > Forschungszentren |
Titel an der UBT entstanden: | Ja |
Themengebiete aus DDC: | 500 Naturwissenschaften und Mathematik |
Eingestellt am: | 11 Sep 2015 06:35 |
Letzte Änderung: | 03 Mai 2016 10:29 |
URI: | https://eref.uni-bayreuth.de/id/eprint/19403 |