Fraunhofer-Institut für Atmosphärische Umweltforschung IFU

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  • Patent
    Verfahren zur Ermittlung der Nitrifikations- und/oder Denitrifikationsrate von Boeden und Vorrichtung hierzu
    ( 2003)
    Butterbach-Bahl, K.
    DE 19906872 A UPAB: 20001023 NOVELTY - Determining soil nitrification and denitrification rates comprising introducing a soil sample into a gas- and pressure-tight vessel to leave a gas space above the soil, hermetically sealing the vessel, and measuring the pressure, and oxygen (O2) and carbon dioxide (CO2) concentrations at least at the start and end of an incubation period of 0.5-24 hours, is new. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for apparatus for carrying out the novel method, comprising a sealable gas-tight vessel having at least one pressure sensor access port and at least one sealable inlet. USE - For determining soil nitrification and denitrification rates using a complex set of equations given in the specification. ADVANTAGE - The method is simple and inexpensive.
  • Publication
    Exchange of trace gases between soils and the atmosphere in Scots pine forest ecosystems of the northeastern German lowlands
    ( 2002)
    Butterbach-Bahl, K.
    ;
    Breuer, L.
    ;
    Gasche, R.
    ;
    Willibald, G.
    ;
    Papen, H.
  • Publication
  • Publication
    N2O and CH4-fluxes from soils of a N-limited and N-fertilized spruce forest ecosystem of the temperate zone
    ( 2001)
    Papen, H.
    ;
    Daum, M.
    ;
    Steinkamp, R.
    ;
    Butterbach-Bahl, K.
    Based on a 3-year data set from measurements of N2O fluxes from soil of a N-limited spruce forest ecosystem it could be demonstrated for the first time that such soils can function as a sink rather than a source for atmospheric N2O. The results suggest that N2O uptake from the atmosphere into the soil is catalyzed by soil denitrifiers which are able to use N2O from the atmosphere instead of nitrate as an electron acceptor for denitrification due to severe limitations of nitrate in the soil. This interpretation is in accordance with the finding that net nitrate production via nitrification was zero or only marginal in the soil of the unfertilized site. On the other hand, the results strongly indicate that atmospheric N-input - simulated in this experiment by ammonium sulfate application (150 kg N ha(-1)) to the forest soil - can lead to a change of the function of the soil of a N-limited forest ecosystem from a sink to a net source of atmospheric N2O. This change was most likely due to stimulation of N2O production via nitrification and denitrification after N-fertilization. N-fertilization lead to a partial inhibition of atmospheric CH4 oxidation. However, this inhibition lasted only short term after N-fertilization and even changed at the end of the observation period to a weak stimulation of CH4 uptake activity at the N-fertilized site when soil ammonium concentrations at this site had decreased to values which were only slightly higher as compared to the unfertilized site. This indicates that at the unfertilized site atmospheric methane oxidizers were N-limited for growth.
  • Publication
    Scanning electron microscopy analysis of the aerenchyma in two rice cultivars
    ( 2000)
    Butterbach-Bahl, K.
    ;
    Papen, H.
    ;
    Rennenberg, H.
    An zwei Reisvarietäten, die in vorangegangenen Freiland- und Labor-Untersuchungen Unterschiede in der Gastransportkapazität des Aerenchymsystems zeigten, wurden rasterelektronenmikroskopische Untersuchungen zur Beschreibung der Anatomie und Konstruktion des Aerenchymsystems in verschiedenen Pflanzenabschnitten (Wurzel, Wurzel-Spross-Übergang, Blattscheide, Blattspreite, Halm) durchgeführt. Die Untersuchungen konzentrierten sich auf die Identifizierung a) von Restriktionen des Gastransports innerhalb des pflanzlichen Aerenchyms sowie b) morphologischer Voraussetzungen für den schon früher beobachteten Gasaustausch zwischen Boden und Aerenchym bzw. Boden und Atmosphäre. Es konnten keine signifikanten Unterschiede in der räumlichen Ausdehnung bzw. der Anatomie des Aerenchyms zwischen den beiden untersuchten Reisvarietäten nachgewiesen werden.CH4-Konzentrationsmessungen in verschiedenen Sproßabschnitten zeigten, dass die Emission von CH4 aus dem pflanzlichen Aerenchym in die Atmosphäre im wesentlichen über die Blattscheiden erfolgte. Als hauptsächlicher Restriktor des Gastransports im pflanzlichen Aerenchymsystem erwiesen sich Lagen parenchymatischer Zellen (Dicke ca. 40 - 50 µm) die zwischen Wurzelaerenchym und Aerechym des Sprosses gefunden wurden. In zukünftigen Arbeiten sollten die Eigenschaften dieses den Gasaustausch innerhalb der Pflanze modulierenden Gewebeabschnitts verstärkt untersucht werden.
  • Publication
    Modellierung von Beziehungen zwischen der Emission von N-Spurengasen aus Waldböden und den Vegetationsstrukturen in Kiefernökosystemen des nordostdeutschen Tieflandes
    ( 2000)
    Jenssen, M.
    ;
    Butterbach-Bahl, K.
    ;
    Hofmann, G.
    ;
    Papen, H.
    Die kleinflächig gemessenen Emissionsraten der primär bzw. sekundär klimarelevanten Spurengase N2O und NO aus Wäldböden nordostdeutscher Kiefernbestände sind hochsignifikant von den auf den Meßplots ausgebildeten Mustern der Bodenvegetation sowie der Struktur des Kronendachs über den Meßplots abhängig. Über die Modellierung dieser Zusammenhänge werden mittlere horizontale Verteilungsmuster der Spurengas-Emissionen am Waldboden (Mesostrukturebene) sowie mittlere Emissionsraten für verbreitete Kiefern-Forstökosysteme (Makrostrukturebene) abgeleitet. Auf der Mesostrukturebene ist eine deutliche Abhängigkeit von der durch das Kronendach gesteuerten kleinräumigen N-Eintrags- und Niederschlagsverteilung erkennbar. Auf der Makrostrukturebene sind der Ökosystemtyp und der atmosphärische N-Eintrag die entscheidenden Steuergrößen für die N2O- und NO-Emissionen. Hiermit ist prinzipiell die Möglichkeit eröffnet, N-Emissionen aus Waldböden im regionalen Maßstab zu kalkulieren.
  • Publication
    Evaluating annual nitrous oxide fluxes at the ecosystem scale
    ( 2000)
    Groffman, P.M.
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    Brumme, R.
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    Butterbach-Bahl, K.
    ;
    Dobbie, K.
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    Mosier, A.R.
    ;
    Ojima, D.S.
    ;
    Papen, H.
    ;
    Parton, W.J.
    ;
    Smith, K.A.
    ;
    Wagner-Riddle, C.
    Evaluation of N2O flux has been one of the most problematic topics in environmental biogeochemistry over the last 10 - 15 years. Early ideas that we should be able to use the large body of existing research on terrestrial N cycling to predict patterns of N2O flux at the ecosystem scale have been hard to prove due to extreme temporal and spatial variability in flux. The vast majority of the N2O flux measurement and modeling activity that has taken place has been process level and field scale, i. e., measurement, analysis and modeling of hourly and daily fluxes with chambers deployed in field plots. It has been very difficult to establish strong predictive relationships between these hourly and daily fluxes and field-scale parameters such as temperature, soil moisture, and soil inorganic N concentrations. In this study, we addressed the question of whether we can increase our predictive understanding of N2O fluxes by examining relationships between flux and environmental parameters at larger spatial and temporal scales, i. e., to explore relationships between annual rather than hourly or daily fluxes and ecosystem-scale variables such as plant community and soil type and annual climate rather than field-scale variables such as soil moisture and temperature. We addressed this question by examining existing data on annual fluxes from temperate forest, cropland, and rangeland ecosystems, analyzing both multiyear data sets from individual sites as well as cross-site comparison of single annual flux values from multiple sites. Results suggest that there are indeed coherent patterns in annual N2O flux at the ecosystem scale in forest, cropland, and rangeland ecosystems but that these patterns vary by region and only emerge with continuous (at least daily) flux measurements over multiple years. An ecosystem approach to evaluating N2O fluxes will be useful for regional and global modeling and for computation of national N2O flux inventories for regulatory purposes but only if measurement programs are comprehensive and continuous.
  • Publication
    N2O emission from tropical forest soils of Australia
    ( 2000)
    Breuer, L.
    ;
    Papen, H.
    ;
    Butterbach-Bahl, K.
    Three different tropical rain forest sites (Kauri Creek, Lake Eacham, and Massey Creek) on the Atherton Tablelands, Queensland, Australia, were investigated for the magnitude of N2O emission from soils during different seasons, that is, wet season, dry season, and transition periods. Highest mean N2O emission rates were observed for soils derived from granite at the Kauri Creek site with 74.5 + 25.2 µg N2O-N m high -2 h high -1, whereas for soils derived from Metamorphics (Lake Eacham site) mean N2O emission rates were much lower (13.1 + 1.1 µg N2O-N m high -2 h high -1). For the Massey Creek site, with soils derived from Rhyolite, a mean annual N2O emission rate of 46.2 + 1.1 µg N2O-N m high -2 h high -1 was calculated. The mean annual N2O emission rate calculated for all three sites over the entire observation period was 39.0 µg N2O-N m high -2 h high -1 and thus at the high end of reports from tropical rain forest soils. N2O emission rates showed at all sites pronounced temporal as well as spatial variability. The magnitude of N2O emissions was strongly linked to rainfall events; that is, N2O emissions strongly increased approximately 6-8 hours after precipitation. Correlation analysis confirmed the strong dependency of N2O emissions on changes in soil moisture, whereas changes in soil temperature did not mediate considerable changes in N2O fluxes. Spatial variability of N2O fluxes on a site scale could be explained best by differences in water-filled pore space, CO2 emission, and C/N ratio of the soil. On the basis of all published N2O flux rates from tropical rain forest soils we recalculated the contribution of such forests to the global atmospheric N2O budget and come up with a figure of 3.55 Tg N2O-N yr high -1, which is approximately 50 % higher than reported by others.
  • Publication
    Impact of changes in temperature and precipitation on N2O and NO emissions from forest soils
    ( 2000)
    Butterbach-Bahl, K.
    ;
    Stange, F.
    ;
    Papen, H.
    ;
    Grell, G.
    ;
    Li, C.