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Hermann F. Jungkunst - One of the best experts on this subject based on the ideXlab platform.
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N2O emissions of a mature Norway spruce (Picea abies) stand in the Black Forest (southwest Germany) as differentiated by the soil pattern
Journal of Geophysical Research, 2004Co-Authors: Hermann F. Jungkunst, Sabine Fiedler, Karl StahrAbstract:[1] Nitrous oxide is a greenhouse gas contributing to stratospheric ozone depletion with major sources that derive from soils. Most measurements were performed at well-aerated or anaerobic sites, excluding common hydromorphic soils (e.g., Gleysols). The main thesis of this study was that the intermediate aeration of such soils promotes N2O emissions. The investigated catena “Wildmooswald,” which is little more than 200 m long, includes common temperate forest soils (n = 7) of three aeration categories (Cambisols, Gleysols, and Histosol). The influence of fluctuating water tables of the Gleysols led to distinctively higher N2O release compared to the Cambisol within the same mature Norway spruce ecosystem. Even a stable “hot spot” of N2O emissions was detected at a Histosol, where artificial drainage created a redox environment comparable to the Gleysols. Ranking the soils according to emission rate results in fairly regular doubling steps; for example, mean annual flux rates in kg N ha−1 yr−1 for the 2.5 years of measurements were −0.1, 0.4, 1.0, 1.9/1.9, 3.2, and 6.4 for Fibric Histosol, Chromic Cambisol, Endoskeletic Cambisol, Histic Gleysol 1/2, Humic Gleysol, and Sapric Histosol, respectively. The annual emission rates (0.93 kg N ha−1 yr−1) of the predominant Cambisols (63.4% of the area) are comparable to other studies, but only 34.3% of intermediately aerated soils led to a redoubling of the average to 1.86 kg N ha−1 yr−1, which is clearly higher than previously presented from temperate forests. Therefore N2O releases of soils are underestimated if soils having intermediate aeration conditions are left unconsidered.
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N2O emissions of a mature Norway spruce (Picea abies) stand in the Black Forest (southwest Germany) as differentiated by the soil pattern
Journal of Geophysical Research, 2004Co-Authors: Hermann F. JungkunstAbstract:Nitrous oxide is a greenhouse gas contributing to stratospheric ozone depletion with major sources that derive from soils. Most measurements were performed at well-aerated or anaerobic sites, excluding common hydromorphic soils (e.g., Gleysols). The main thesis of this study was that the intermediate aeration of such soils promotes N2O emissions. The investigated catena "Wildmooswald,'' which is little more than 200 m long, includes common temperate forest soils (n=7) of three aeration categories (Cambisols, Gleysols, and Histosol). The influence of fluctuating water tables of the Gleysols led to distinctively higher N2O release compared to the Cambisol within the same mature Norway spruce ecosystem. Even a stable "hot spot'' of N2O emissions was detected at a Histosol, where artificial drainage created a redox environment comparable to the Gleysols. Ranking the soils according to emission rate results in fairly regular doubling steps; for example, mean annual flux rates in kg N ha(-1) yr(-1) for the 2.5 years of measurements were -0.1, 0.4, 1.0, 1.9/1.9, 3.2, and 6.4 for Fibric Histosol, Chromic Cambisol, Endoskeletic Cambisol, Histic Gleysol 1/2, Humic Gleysol, and Sapric Histosol, respectively. The annual emission rates (0.93 kg N ha(-1) yr(-1)) of the predominant Cambisols (63.4% of the area) are comparable to other studies, but only 34.3% of intermediately aerated soils led to a redoubling of the average to 1.86 kg N ha(-1) yr(-1), which is clearly higher than previously presented from temperate forests. Therefore N2O releases of soils are underestimated if soils having intermediate aeration conditions are left unconsidered. [References: 42
Karl Stahr - One of the best experts on this subject based on the ideXlab platform.
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N2O emissions of a mature Norway spruce (Picea abies) stand in the Black Forest (southwest Germany) as differentiated by the soil pattern
Journal of Geophysical Research, 2004Co-Authors: Hermann F. Jungkunst, Sabine Fiedler, Karl StahrAbstract:[1] Nitrous oxide is a greenhouse gas contributing to stratospheric ozone depletion with major sources that derive from soils. Most measurements were performed at well-aerated or anaerobic sites, excluding common hydromorphic soils (e.g., Gleysols). The main thesis of this study was that the intermediate aeration of such soils promotes N2O emissions. The investigated catena “Wildmooswald,” which is little more than 200 m long, includes common temperate forest soils (n = 7) of three aeration categories (Cambisols, Gleysols, and Histosol). The influence of fluctuating water tables of the Gleysols led to distinctively higher N2O release compared to the Cambisol within the same mature Norway spruce ecosystem. Even a stable “hot spot” of N2O emissions was detected at a Histosol, where artificial drainage created a redox environment comparable to the Gleysols. Ranking the soils according to emission rate results in fairly regular doubling steps; for example, mean annual flux rates in kg N ha−1 yr−1 for the 2.5 years of measurements were −0.1, 0.4, 1.0, 1.9/1.9, 3.2, and 6.4 for Fibric Histosol, Chromic Cambisol, Endoskeletic Cambisol, Histic Gleysol 1/2, Humic Gleysol, and Sapric Histosol, respectively. The annual emission rates (0.93 kg N ha−1 yr−1) of the predominant Cambisols (63.4% of the area) are comparable to other studies, but only 34.3% of intermediately aerated soils led to a redoubling of the average to 1.86 kg N ha−1 yr−1, which is clearly higher than previously presented from temperate forests. Therefore N2O releases of soils are underestimated if soils having intermediate aeration conditions are left unconsidered.
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Oxidation of methane and dehydrogenase activity in a Mollic Gleysol
Journal of Plant Nutrition and Soil Science, 1998Co-Authors: Małgorzata Brzezińska, Teresa Włodarczyk, Karl Stahr, Yakov Kuzyakov, Witold StȩpniewskiAbstract:It was found that during a 4-day incubation of a Mollic Gleysol with 352 μl 1−1 methane in the headspace, the rate of methane consumption declined exponentially from an initial value of 9.13 μmol kg−1 hour−1 (about 5% of total CO2 evolved) according to first-order kinetics. The increase of dehydrogenase activity due to methane amendment did not exceed 15% of the control value and reached the maximum after two days of incubation. Methanoxidation und Dehydrogenaseaktivitat eines Mollic Gleysol Die Dehydrogenaseaktivitat eines Mollic Gleysols nach Methanzugabe (352 μl 1−1) wurde in einem 4 Tage dauernden Modellexperiment untersucht. Die Geschwindigkeit der CH4−Oxidation nahm exponentiell von 9.13 μMol CO2 kg−1 h−1 (ca. 5% des Gesamt-CO2−Effluxes des Bodens) gemas einer Reaktion 1. Ordnung ab. Die Zunahme der Dehydrogenaseaktivitat unter Einflus der CH4−Zugahe blieb unter 15% der Kontrolle und erreichte nach zwei Inkubationslagen ihr Maximum.
Burkhard Neuwirth - One of the best experts on this subject based on the ideXlab platform.
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Growth and wood isotopic signature of Norway spruce (Picea abies) along a small-scale gradient of soil moisture.
Tree Physiology, 2018Co-Authors: Frank M. Thomas, Andreas Rzepecki, Andreas Lücke, Inge Wiekenkamp, Inken Rabbel, Thomas Pütz, Burkhard NeuwirthAbstract:: Among the environmental factors that have an effect on the isotopic signature of tree rings, the specific impact of soil moisture on the Δ13C and, in particular, the δ18O ratios has scarcely been investigated. We studied the effects of soil type and soil moisture (from moderately moist [Cambisol] to wet [Gleysol]) on the growth and isotopic signature of tree rings of Norway spruce (Picea abies [L.] H. Karst.), a widely distributed forest tree species in Central Europe, at a small spatial scale in a typical mature forest plantation in the low mountain ranges of Western Germany. The δ18O ratios were lower in rings of trees growing at the wettest microsite (Gleysol) than in tree rings from the microsite with moderately moist soil (Cambisol). This indicates higher uptake rates of 18O-unenriched soil water at the Gleysol microsite and corresponds to less negative soil water potentials and higher transpiration rates on the Gleysol plots. Contrary to our expectations, the basal area increments, the Δ13C ratios and the intrinsic water-use efficiency (calculated on the basis of δ13C) did not differ significantly between the Cambisol and the Gleysol microsites. For average values of each microsite and year investigated, we found a significantly positive correlation between δ13C and δ18O, which indicates a consistent stomatal control over gas exchange along the soil moisture gradient at comparable relative air humidity in the stand. As δ18O ratios of tree rings integrate responses of wood formation to soil moisture over longer periods of time, they may help to identify microsites differing in soil water availability along small-scale gradients of soil moisture under homogeneous climatic conditions and to explain the occurrence of particular tree species along those gradients in forest stands.
Frank M. Thomas - One of the best experts on this subject based on the ideXlab platform.
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Growth and wood isotopic signature of Norway spruce (Picea abies) along a small-scale gradient of soil moisture.
Tree Physiology, 2018Co-Authors: Frank M. Thomas, Andreas Rzepecki, Andreas Lücke, Inge Wiekenkamp, Inken Rabbel, Thomas Pütz, Burkhard NeuwirthAbstract:: Among the environmental factors that have an effect on the isotopic signature of tree rings, the specific impact of soil moisture on the Δ13C and, in particular, the δ18O ratios has scarcely been investigated. We studied the effects of soil type and soil moisture (from moderately moist [Cambisol] to wet [Gleysol]) on the growth and isotopic signature of tree rings of Norway spruce (Picea abies [L.] H. Karst.), a widely distributed forest tree species in Central Europe, at a small spatial scale in a typical mature forest plantation in the low mountain ranges of Western Germany. The δ18O ratios were lower in rings of trees growing at the wettest microsite (Gleysol) than in tree rings from the microsite with moderately moist soil (Cambisol). This indicates higher uptake rates of 18O-unenriched soil water at the Gleysol microsite and corresponds to less negative soil water potentials and higher transpiration rates on the Gleysol plots. Contrary to our expectations, the basal area increments, the Δ13C ratios and the intrinsic water-use efficiency (calculated on the basis of δ13C) did not differ significantly between the Cambisol and the Gleysol microsites. For average values of each microsite and year investigated, we found a significantly positive correlation between δ13C and δ18O, which indicates a consistent stomatal control over gas exchange along the soil moisture gradient at comparable relative air humidity in the stand. As δ18O ratios of tree rings integrate responses of wood formation to soil moisture over longer periods of time, they may help to identify microsites differing in soil water availability along small-scale gradients of soil moisture under homogeneous climatic conditions and to explain the occurrence of particular tree species along those gradients in forest stands.
Neli Jordanova - One of the best experts on this subject based on the ideXlab platform.
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The magnetism of soils distinguished by iron/aluminum chemistry: Planosols, Pozdols, Andosols, Ferralsols, and Gleysols
Soil Magnetism, 2017Co-Authors: Neli JordanovaAbstract:In this chapter, detailed magnetic studies of soil profiles of Planosols, Pozdols, Andosols, Ferralsols, and Gleysols give an overview of the diversity and sensitivity of soil magnetic properties to various environmental settings. The magnetic signature of three Planosol profiles consistently demonstrates nonsynchronous distribution of the different magnetic grain-size fractions along the depth, related to the specific hydrologic regimen. Podzols, despite being dominated by amorphous iron oxide forms, show in their magnetic signature the presence of a magnetically soft stable (single-domain) mineral component of pedogenic origin. Magnetism of Andosols, though dominated by lithology-inherited magnetic fraction, could also be used for their pedogenic characterization. Magnetism of highly weathered tropical Ferralsols can be regarded as an ultimate expression of iron oxide transformations under oxic conditions but their magnetic signature needs further elucidation. Magnetic properties of Gleysols demonstrate the effects of reductive dissolution of iron oxides in soils.
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the magnetism of soils distinguished by iron aluminum chemistry planosols pozdols andosols ferralsols and Gleysols
Soil Magnetism#R##N#Applications in Pedology Environmental Science and Agriculture, 2017Co-Authors: Neli JordanovaAbstract:In this chapter, detailed magnetic studies of soil profiles of Planosols, Pozdols, Andosols, Ferralsols, and Gleysols give an overview of the diversity and sensitivity of soil magnetic properties to various environmental settings. The magnetic signature of three Planosol profiles consistently demonstrates nonsynchronous distribution of the different magnetic grain-size fractions along the depth, related to the specific hydrologic regimen. Podzols, despite being dominated by amorphous iron oxide forms, show in their magnetic signature the presence of a magnetically soft stable (single-domain) mineral component of pedogenic origin. Magnetism of Andosols, though dominated by lithology-inherited magnetic fraction, could also be used for their pedogenic characterization. Magnetism of highly weathered tropical Ferralsols can be regarded as an ultimate expression of iron oxide transformations under oxic conditions but their magnetic signature needs further elucidation. Magnetic properties of Gleysols demonstrate the effects of reductive dissolution of iron oxides in soils.