The Experts below are selected from a list of 306 Experts worldwide ranked by ideXlab platform
Cornelia Rumpel - One of the best experts on this subject based on the ideXlab platform.
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Soil Organic Matter and environmental impacts of Integrated Crop-livestock: What do we know?
2013Co-Authors: Abad Chabbi, Cornelia Rumpel, Karen Baumann, Laurent Remusat, Pierre Barre, Marie-france DignacAbstract:Soil Organic Matter and environmental impacts of Integrated Crop-livestock: What do we know?. 4th International Symposium on Soil Organic Matter
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evolution of Soil Organic Matter after prescribed fire a 20 year chronosequence
Geoderma, 2012Co-Authors: Marie Alexis, Heike Knicker, D. P. Rasse, C. Anquetil, Cornelia RumpelAbstract:Abstract Vegetation fires influence the properties and turnover of Soil Organic Matter in numerous ecosystems. Thermal alteration tends to increase the stability of Soil Organic Matter. Fire induces the destruction of above‐ground biomass, which is associated with a large production of new partially-charred litter. Plant regeneration is directly affected by the fire itself, and by the ensuing modifications to the C, N and nutrient cycles associated with Soil Organic Matter transformations. The objectives of the present study were to determine 1) changes in Soil Organic Matter composition induced by fire, and 2) the dynamics of Soil Organic Matter recovery in the first two decades following a fire event.. In a Florida scrub oak ecosystem, a chronosequence of Soils protected from vegetation fire for 1 to 20 years was studied. The bulk Organic Matter and oxidation resistant elemental carbon were quantified in depths 0–5 cm, 5–15 cm, and 15–25 cm. The Soil Organic Matter was characterized by solid-state 13 C NMR spectroscopy and Curie point pyrolysis. The combination of these techniques allowed us to identify three steps in Soil Organic Matter evolution: first the un-charred litter brought by the fire degraded between 1 and 4 years after fire; second the contribution of aryl carbon, and most probably the pyrogenic carbon, significantly decreased between 4 and 11 years after fire; Thirdly, after 11 years, the Soil Organic Matter quality appeared driven again by the fresh litter input from regenerating plant ecosystem. In this study, the Soil Organic Matter did not appear strongly modified by the fire. The pyrogenic carbon did not dominate the Soil Organic Matter composition and underwent significant degradation at the decadal timescale. Our results also highlight a potential underestimated effect of dead root input to Soil Organic Matter after the fire.
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Evolution of Soil Organic Matter after prescribed fire: A 20-year chronosequence
Geoderma, 2012Co-Authors: M. A. Alexis, Heike Knicker, D. P. Rasse, C. Anquetil, Cornelia RumpelAbstract:Vegetation fires influence the properties and turnover of Soil Organic Matter in numerous ecosystems. Thermal alteration tends to increase the stability of Soil Organic Matter. Fire induces the destruction of above-ground biomass, which is associated with a large production of new partially-charred litter. Plant regeneration is directly affected by the fire itself, and by the ensuing modifications to the C, N and nutrient cycles associated with Soil Organic Matter transformations. The objectives of the present study were to determine 1) changes in Soil Organic Matter composition induced by fire, and 2) the dynamics of Soil Organic Matter recovery in the first two decades following a fire event.. In a Florida scrub oak ecosystem, a chronosequence of Soils protected from vegetation fire for 1 to 20 years was studied. The bulk Organic Matter and oxidation resistant elemental carbon were quantified in depths 0-5 cm, 5-15 cm, and 15-25 cm. The Soil Organic Matter was characterized by solid-state C-13 NMR spectroscopy and Curie point pyrolysis. The combination of these techniques allowed us to identify three steps in Soil Organic Matter evolution: first the un-charred litter brought by the fire degraded between 1 and 4 years after fire: second the contribution of aryl carbon, and most probably the pyrogenic carbon, significantly decreased between 4 and 11 years after fire: Thirdly, after 11 years, the Soil Organic Matter quality appeared driven again by the fresh litter input from regenerating plant ecosystem. In this study, the Soil Organic Matter did not appear strongly modified by the fire. The pyrogenic carbon did not dominate the Soil Organic Matter composition and underwent significant degradation at the decadal timescale. Our results also highlight a potential underestimated effect of dead root input to Soil Organic Matter after the fire. (C) 2012 Elsevier B.V. All rights reserved.
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Evolution of Soil Organic Matter after prescribed fire: A 20-year chronosequence
Geoderma, 2012Co-Authors: M. A. Alexis, Heike Knicker, D. P. Rasse, C. Anquetil, Cornelia RumpelAbstract:Vegetation fires influence the properties and turnover of Soil Organic Matter in numerous ecosystems. Thermal alteration tends to increase the stability of Soil Organic Matter. Fire induces the destruction of above-ground biomass, which is associated with a large production of new partially-charred litter. Plant regeneration is directly affected by the fire itself, and by the ensuing modifications to the C, N and nutrient cycles associated with Soil Organic Matter transformations. The objectives of the present study were to determine 1) changes in Soil Organic Matter composition induced by fire, and 2) the dynamics of Soil Organic Matter recovery in the first two decades following a fire event.. In a Florida scrub oak ecosystem, a chronosequence of Soils protected from vegetation fire for 1 to 20years was studied. The bulk Organic Matter and oxidation resistant elemental carbon were quantified in depths 0-5cm, 5-15cm, and 15-25cm. The Soil Organic Matter was characterized by solid-state 13C NMR spectroscopy and Curie point pyrolysis.The combination of these techniques allowed us to identify three steps in Soil Organic Matter evolution: first the un-charred litter brought by the fire degraded between 1 and 4. years after fire; second the contribution of aryl carbon, and most probably the pyrogenic carbon, significantly decreased between 4 and 11. years after fire; Thirdly, after 11. years, the Soil Organic Matter quality appeared driven again by the fresh litter input from regenerating plant ecosystem. In this study, the Soil Organic Matter did not appear strongly modified by the fire. The pyrogenic carbon did not dominate the Soil Organic Matter composition and underwent significant degradation at the decadal timescale. Our results also highlight a potential underestimated effect of dead root input to Soil Organic Matter after the fire.Peer Reviewe
P. Smith - One of the best experts on this subject based on the ideXlab platform.
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The changing faces of Soil Organic Matter research
European Journal of Soil Science, 2018Co-Authors: P. Smith, Suzanne Lutfalla, W. J. Riley, M. S. Torn, M. W. I. Schmidt, Jean-françois SoussanaAbstract:For the 70th Anniversary of the establishment of the British Society of Soil Science, this short paper explores the idea that research on Soil Organic Matter has remained a central theme within Soil science over the past 70 years, albeit with changing emphasis and application. The number of publications on Soil Organic Matter has increased greatly in recent decades; for example, there were almost 35 000 journal papers with this theme in the decade 2007-2016. Several topics in research on Soil Organic Matter, such as Soil fertility, have endured for a number of decades, with publications found on Soil Organic Matter and fertility in the decade 1947-1956. A search with other keywords occurring with Soil, such as climate change, biodiversity, fertility, quality, health and security, showed that several topics did not appear before the 1970s and 1980s, but since then the sub-topics and applications have diversified. Carbon is a keyword that has become more associated with publications on Soil Organic Matter; carbon is in over half of Soil Organic Matter publications of the last decade. A closer examination of research on agricultural Soil carbon sequestration since 1990 reveals that the focus of papers in the literature has changed over this period. A closer examination of papers on modelling shows that the next generation of Soil Organic Matter models is developing from pseudo first-order decay models using conceptual pools and prescribed controls of turnover time to vertically resolved, microbially explicit models representing mineral surface and plant interactions. Given its higher policy profile during the last 2 years, research on Soil Organic Matter and Soil carbon sequestration is predicted to have a bright future. Highlights The number of publications on Soil Organic Matter has increased greatly in recent decades. Soil fertility research has endured for many decades, whereas other topics have diversified. Soil Organic Matter has been increasingly associated with carbon, which has changed the focus of papers since 1990. Expanding policy attention to Soil Organic Matter research during the last 2 years suggests a bright future.
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The changing faces of Soil Organic Matter research
European Journal of Soil Science, 2017Co-Authors: P. Smith, Suzanne Lutfalla, W. J. Riley, M. S. Torn, M. W. I. Schmidt, Jean-françois SoussanaAbstract:For the 70th Anniversary of the establishment of the British Society of Soil Science, this short paper explores the idea that research on Soil Organic Matter has remained a central theme within Soil science over the past 70 years, albeit with changing emphasis and application. The number of publications on Soil Organic Matter has increased greatly in recent decades; for example, there were almost 35 000 journal papers with this theme in the decade 2007–2016. Several topics in research on Soil Organic Matter, such as Soil fertility, have endured for a number of decades, with publications found on Soil Organic Matter and fertility in the decade 1947–1956. A search with other keywords occurring with Soil, such as climate change, biodiversity, fertility, quality, health and security, showed that several topics did not appear before the 1970s and 1980s, but since then the sub-topics and applications have diversified. Carbon is a keyword that has become more associated with publications on Soil Organic Matter; carbon is in over half of Soil Organic Matter publications of the last decade. A closer examination of research on agricultural Soil carbon sequestration since 1990 reveals that the focus of papers in the literature has changed over this period. A closer examination of papers on modelling shows that the next generation of Soil Organic Matter models is developing from pseudo first-order decay models using conceptual pools and prescribed controls of turnover time to vertically resolved,microbially explicit models representingmineral surface and plant interactions. Given its higher policy profile during the last 2 years, research on Soil Organic Matter and Soil carbon sequestration is predicted to have a bright future.
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Establishing a European GCTE Soil Organic Matter Network (SOMNET)
Evaluation of Soil Organic Matter Models, 1996Co-Authors: P. Smith, David S. Powlson, Margaret J. GlendiningAbstract:Soil Organic Matter (SOM) is recognised as being of critical importance as a source and sink of carbon in the biosphere. As a result, research into predicting the effects of global environmental change on Soil Organic Matter has been identified as a high priority within the Global Change and Terrestrial Ecosystems (GCTE) programme of the International Geosphere-Biosphere Programme (IGBP). The objectives of GCTE Task 3.3.1., “Soil Organic Matter” require that a global network of SOM modellers and experimenters be established. This global Soil Organic Matter network (SOMNET) will comprise a number of regional networks, one of which will be the European GCTE SOMNET.
D. P. Rasse - One of the best experts on this subject based on the ideXlab platform.
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evolution of Soil Organic Matter after prescribed fire a 20 year chronosequence
Geoderma, 2012Co-Authors: Marie Alexis, Heike Knicker, D. P. Rasse, C. Anquetil, Cornelia RumpelAbstract:Abstract Vegetation fires influence the properties and turnover of Soil Organic Matter in numerous ecosystems. Thermal alteration tends to increase the stability of Soil Organic Matter. Fire induces the destruction of above‐ground biomass, which is associated with a large production of new partially-charred litter. Plant regeneration is directly affected by the fire itself, and by the ensuing modifications to the C, N and nutrient cycles associated with Soil Organic Matter transformations. The objectives of the present study were to determine 1) changes in Soil Organic Matter composition induced by fire, and 2) the dynamics of Soil Organic Matter recovery in the first two decades following a fire event.. In a Florida scrub oak ecosystem, a chronosequence of Soils protected from vegetation fire for 1 to 20 years was studied. The bulk Organic Matter and oxidation resistant elemental carbon were quantified in depths 0–5 cm, 5–15 cm, and 15–25 cm. The Soil Organic Matter was characterized by solid-state 13 C NMR spectroscopy and Curie point pyrolysis. The combination of these techniques allowed us to identify three steps in Soil Organic Matter evolution: first the un-charred litter brought by the fire degraded between 1 and 4 years after fire; second the contribution of aryl carbon, and most probably the pyrogenic carbon, significantly decreased between 4 and 11 years after fire; Thirdly, after 11 years, the Soil Organic Matter quality appeared driven again by the fresh litter input from regenerating plant ecosystem. In this study, the Soil Organic Matter did not appear strongly modified by the fire. The pyrogenic carbon did not dominate the Soil Organic Matter composition and underwent significant degradation at the decadal timescale. Our results also highlight a potential underestimated effect of dead root input to Soil Organic Matter after the fire.
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Evolution of Soil Organic Matter after prescribed fire: A 20-year chronosequence
Geoderma, 2012Co-Authors: M. A. Alexis, Heike Knicker, D. P. Rasse, C. Anquetil, Cornelia RumpelAbstract:Vegetation fires influence the properties and turnover of Soil Organic Matter in numerous ecosystems. Thermal alteration tends to increase the stability of Soil Organic Matter. Fire induces the destruction of above-ground biomass, which is associated with a large production of new partially-charred litter. Plant regeneration is directly affected by the fire itself, and by the ensuing modifications to the C, N and nutrient cycles associated with Soil Organic Matter transformations. The objectives of the present study were to determine 1) changes in Soil Organic Matter composition induced by fire, and 2) the dynamics of Soil Organic Matter recovery in the first two decades following a fire event.. In a Florida scrub oak ecosystem, a chronosequence of Soils protected from vegetation fire for 1 to 20 years was studied. The bulk Organic Matter and oxidation resistant elemental carbon were quantified in depths 0-5 cm, 5-15 cm, and 15-25 cm. The Soil Organic Matter was characterized by solid-state C-13 NMR spectroscopy and Curie point pyrolysis. The combination of these techniques allowed us to identify three steps in Soil Organic Matter evolution: first the un-charred litter brought by the fire degraded between 1 and 4 years after fire: second the contribution of aryl carbon, and most probably the pyrogenic carbon, significantly decreased between 4 and 11 years after fire: Thirdly, after 11 years, the Soil Organic Matter quality appeared driven again by the fresh litter input from regenerating plant ecosystem. In this study, the Soil Organic Matter did not appear strongly modified by the fire. The pyrogenic carbon did not dominate the Soil Organic Matter composition and underwent significant degradation at the decadal timescale. Our results also highlight a potential underestimated effect of dead root input to Soil Organic Matter after the fire. (C) 2012 Elsevier B.V. All rights reserved.
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Evolution of Soil Organic Matter after prescribed fire: A 20-year chronosequence
Geoderma, 2012Co-Authors: M. A. Alexis, Heike Knicker, D. P. Rasse, C. Anquetil, Cornelia RumpelAbstract:Vegetation fires influence the properties and turnover of Soil Organic Matter in numerous ecosystems. Thermal alteration tends to increase the stability of Soil Organic Matter. Fire induces the destruction of above-ground biomass, which is associated with a large production of new partially-charred litter. Plant regeneration is directly affected by the fire itself, and by the ensuing modifications to the C, N and nutrient cycles associated with Soil Organic Matter transformations. The objectives of the present study were to determine 1) changes in Soil Organic Matter composition induced by fire, and 2) the dynamics of Soil Organic Matter recovery in the first two decades following a fire event.. In a Florida scrub oak ecosystem, a chronosequence of Soils protected from vegetation fire for 1 to 20years was studied. The bulk Organic Matter and oxidation resistant elemental carbon were quantified in depths 0-5cm, 5-15cm, and 15-25cm. The Soil Organic Matter was characterized by solid-state 13C NMR spectroscopy and Curie point pyrolysis.The combination of these techniques allowed us to identify three steps in Soil Organic Matter evolution: first the un-charred litter brought by the fire degraded between 1 and 4. years after fire; second the contribution of aryl carbon, and most probably the pyrogenic carbon, significantly decreased between 4 and 11. years after fire; Thirdly, after 11. years, the Soil Organic Matter quality appeared driven again by the fresh litter input from regenerating plant ecosystem. In this study, the Soil Organic Matter did not appear strongly modified by the fire. The pyrogenic carbon did not dominate the Soil Organic Matter composition and underwent significant degradation at the decadal timescale. Our results also highlight a potential underestimated effect of dead root input to Soil Organic Matter after the fire.Peer Reviewe
C. Anquetil - One of the best experts on this subject based on the ideXlab platform.
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evolution of Soil Organic Matter after prescribed fire a 20 year chronosequence
Geoderma, 2012Co-Authors: Marie Alexis, Heike Knicker, D. P. Rasse, C. Anquetil, Cornelia RumpelAbstract:Abstract Vegetation fires influence the properties and turnover of Soil Organic Matter in numerous ecosystems. Thermal alteration tends to increase the stability of Soil Organic Matter. Fire induces the destruction of above‐ground biomass, which is associated with a large production of new partially-charred litter. Plant regeneration is directly affected by the fire itself, and by the ensuing modifications to the C, N and nutrient cycles associated with Soil Organic Matter transformations. The objectives of the present study were to determine 1) changes in Soil Organic Matter composition induced by fire, and 2) the dynamics of Soil Organic Matter recovery in the first two decades following a fire event.. In a Florida scrub oak ecosystem, a chronosequence of Soils protected from vegetation fire for 1 to 20 years was studied. The bulk Organic Matter and oxidation resistant elemental carbon were quantified in depths 0–5 cm, 5–15 cm, and 15–25 cm. The Soil Organic Matter was characterized by solid-state 13 C NMR spectroscopy and Curie point pyrolysis. The combination of these techniques allowed us to identify three steps in Soil Organic Matter evolution: first the un-charred litter brought by the fire degraded between 1 and 4 years after fire; second the contribution of aryl carbon, and most probably the pyrogenic carbon, significantly decreased between 4 and 11 years after fire; Thirdly, after 11 years, the Soil Organic Matter quality appeared driven again by the fresh litter input from regenerating plant ecosystem. In this study, the Soil Organic Matter did not appear strongly modified by the fire. The pyrogenic carbon did not dominate the Soil Organic Matter composition and underwent significant degradation at the decadal timescale. Our results also highlight a potential underestimated effect of dead root input to Soil Organic Matter after the fire.
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Evolution of Soil Organic Matter after prescribed fire: A 20-year chronosequence
Geoderma, 2012Co-Authors: M. A. Alexis, Heike Knicker, D. P. Rasse, C. Anquetil, Cornelia RumpelAbstract:Vegetation fires influence the properties and turnover of Soil Organic Matter in numerous ecosystems. Thermal alteration tends to increase the stability of Soil Organic Matter. Fire induces the destruction of above-ground biomass, which is associated with a large production of new partially-charred litter. Plant regeneration is directly affected by the fire itself, and by the ensuing modifications to the C, N and nutrient cycles associated with Soil Organic Matter transformations. The objectives of the present study were to determine 1) changes in Soil Organic Matter composition induced by fire, and 2) the dynamics of Soil Organic Matter recovery in the first two decades following a fire event.. In a Florida scrub oak ecosystem, a chronosequence of Soils protected from vegetation fire for 1 to 20 years was studied. The bulk Organic Matter and oxidation resistant elemental carbon were quantified in depths 0-5 cm, 5-15 cm, and 15-25 cm. The Soil Organic Matter was characterized by solid-state C-13 NMR spectroscopy and Curie point pyrolysis. The combination of these techniques allowed us to identify three steps in Soil Organic Matter evolution: first the un-charred litter brought by the fire degraded between 1 and 4 years after fire: second the contribution of aryl carbon, and most probably the pyrogenic carbon, significantly decreased between 4 and 11 years after fire: Thirdly, after 11 years, the Soil Organic Matter quality appeared driven again by the fresh litter input from regenerating plant ecosystem. In this study, the Soil Organic Matter did not appear strongly modified by the fire. The pyrogenic carbon did not dominate the Soil Organic Matter composition and underwent significant degradation at the decadal timescale. Our results also highlight a potential underestimated effect of dead root input to Soil Organic Matter after the fire. (C) 2012 Elsevier B.V. All rights reserved.
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Evolution of Soil Organic Matter after prescribed fire: A 20-year chronosequence
Geoderma, 2012Co-Authors: M. A. Alexis, Heike Knicker, D. P. Rasse, C. Anquetil, Cornelia RumpelAbstract:Vegetation fires influence the properties and turnover of Soil Organic Matter in numerous ecosystems. Thermal alteration tends to increase the stability of Soil Organic Matter. Fire induces the destruction of above-ground biomass, which is associated with a large production of new partially-charred litter. Plant regeneration is directly affected by the fire itself, and by the ensuing modifications to the C, N and nutrient cycles associated with Soil Organic Matter transformations. The objectives of the present study were to determine 1) changes in Soil Organic Matter composition induced by fire, and 2) the dynamics of Soil Organic Matter recovery in the first two decades following a fire event.. In a Florida scrub oak ecosystem, a chronosequence of Soils protected from vegetation fire for 1 to 20years was studied. The bulk Organic Matter and oxidation resistant elemental carbon were quantified in depths 0-5cm, 5-15cm, and 15-25cm. The Soil Organic Matter was characterized by solid-state 13C NMR spectroscopy and Curie point pyrolysis.The combination of these techniques allowed us to identify three steps in Soil Organic Matter evolution: first the un-charred litter brought by the fire degraded between 1 and 4. years after fire; second the contribution of aryl carbon, and most probably the pyrogenic carbon, significantly decreased between 4 and 11. years after fire; Thirdly, after 11. years, the Soil Organic Matter quality appeared driven again by the fresh litter input from regenerating plant ecosystem. In this study, the Soil Organic Matter did not appear strongly modified by the fire. The pyrogenic carbon did not dominate the Soil Organic Matter composition and underwent significant degradation at the decadal timescale. Our results also highlight a potential underestimated effect of dead root input to Soil Organic Matter after the fire.Peer Reviewe
Heike Knicker - One of the best experts on this subject based on the ideXlab platform.
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evolution of Soil Organic Matter after prescribed fire a 20 year chronosequence
Geoderma, 2012Co-Authors: Marie Alexis, Heike Knicker, D. P. Rasse, C. Anquetil, Cornelia RumpelAbstract:Abstract Vegetation fires influence the properties and turnover of Soil Organic Matter in numerous ecosystems. Thermal alteration tends to increase the stability of Soil Organic Matter. Fire induces the destruction of above‐ground biomass, which is associated with a large production of new partially-charred litter. Plant regeneration is directly affected by the fire itself, and by the ensuing modifications to the C, N and nutrient cycles associated with Soil Organic Matter transformations. The objectives of the present study were to determine 1) changes in Soil Organic Matter composition induced by fire, and 2) the dynamics of Soil Organic Matter recovery in the first two decades following a fire event.. In a Florida scrub oak ecosystem, a chronosequence of Soils protected from vegetation fire for 1 to 20 years was studied. The bulk Organic Matter and oxidation resistant elemental carbon were quantified in depths 0–5 cm, 5–15 cm, and 15–25 cm. The Soil Organic Matter was characterized by solid-state 13 C NMR spectroscopy and Curie point pyrolysis. The combination of these techniques allowed us to identify three steps in Soil Organic Matter evolution: first the un-charred litter brought by the fire degraded between 1 and 4 years after fire; second the contribution of aryl carbon, and most probably the pyrogenic carbon, significantly decreased between 4 and 11 years after fire; Thirdly, after 11 years, the Soil Organic Matter quality appeared driven again by the fresh litter input from regenerating plant ecosystem. In this study, the Soil Organic Matter did not appear strongly modified by the fire. The pyrogenic carbon did not dominate the Soil Organic Matter composition and underwent significant degradation at the decadal timescale. Our results also highlight a potential underestimated effect of dead root input to Soil Organic Matter after the fire.
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Evolution of Soil Organic Matter after prescribed fire: A 20-year chronosequence
Geoderma, 2012Co-Authors: M. A. Alexis, Heike Knicker, D. P. Rasse, C. Anquetil, Cornelia RumpelAbstract:Vegetation fires influence the properties and turnover of Soil Organic Matter in numerous ecosystems. Thermal alteration tends to increase the stability of Soil Organic Matter. Fire induces the destruction of above-ground biomass, which is associated with a large production of new partially-charred litter. Plant regeneration is directly affected by the fire itself, and by the ensuing modifications to the C, N and nutrient cycles associated with Soil Organic Matter transformations. The objectives of the present study were to determine 1) changes in Soil Organic Matter composition induced by fire, and 2) the dynamics of Soil Organic Matter recovery in the first two decades following a fire event.. In a Florida scrub oak ecosystem, a chronosequence of Soils protected from vegetation fire for 1 to 20 years was studied. The bulk Organic Matter and oxidation resistant elemental carbon were quantified in depths 0-5 cm, 5-15 cm, and 15-25 cm. The Soil Organic Matter was characterized by solid-state C-13 NMR spectroscopy and Curie point pyrolysis. The combination of these techniques allowed us to identify three steps in Soil Organic Matter evolution: first the un-charred litter brought by the fire degraded between 1 and 4 years after fire: second the contribution of aryl carbon, and most probably the pyrogenic carbon, significantly decreased between 4 and 11 years after fire: Thirdly, after 11 years, the Soil Organic Matter quality appeared driven again by the fresh litter input from regenerating plant ecosystem. In this study, the Soil Organic Matter did not appear strongly modified by the fire. The pyrogenic carbon did not dominate the Soil Organic Matter composition and underwent significant degradation at the decadal timescale. Our results also highlight a potential underestimated effect of dead root input to Soil Organic Matter after the fire. (C) 2012 Elsevier B.V. All rights reserved.
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Evolution of Soil Organic Matter after prescribed fire: A 20-year chronosequence
Geoderma, 2012Co-Authors: M. A. Alexis, Heike Knicker, D. P. Rasse, C. Anquetil, Cornelia RumpelAbstract:Vegetation fires influence the properties and turnover of Soil Organic Matter in numerous ecosystems. Thermal alteration tends to increase the stability of Soil Organic Matter. Fire induces the destruction of above-ground biomass, which is associated with a large production of new partially-charred litter. Plant regeneration is directly affected by the fire itself, and by the ensuing modifications to the C, N and nutrient cycles associated with Soil Organic Matter transformations. The objectives of the present study were to determine 1) changes in Soil Organic Matter composition induced by fire, and 2) the dynamics of Soil Organic Matter recovery in the first two decades following a fire event.. In a Florida scrub oak ecosystem, a chronosequence of Soils protected from vegetation fire for 1 to 20years was studied. The bulk Organic Matter and oxidation resistant elemental carbon were quantified in depths 0-5cm, 5-15cm, and 15-25cm. The Soil Organic Matter was characterized by solid-state 13C NMR spectroscopy and Curie point pyrolysis.The combination of these techniques allowed us to identify three steps in Soil Organic Matter evolution: first the un-charred litter brought by the fire degraded between 1 and 4. years after fire; second the contribution of aryl carbon, and most probably the pyrogenic carbon, significantly decreased between 4 and 11. years after fire; Thirdly, after 11. years, the Soil Organic Matter quality appeared driven again by the fresh litter input from regenerating plant ecosystem. In this study, the Soil Organic Matter did not appear strongly modified by the fire. The pyrogenic carbon did not dominate the Soil Organic Matter composition and underwent significant degradation at the decadal timescale. Our results also highlight a potential underestimated effect of dead root input to Soil Organic Matter after the fire.Peer Reviewe
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eMagRes - Soil Organic Matter
eMagRes, 1996Co-Authors: Anne E. Berns, Heike KnickerAbstract:The successful recording of NMR signals nearly 70 years ago started the development of one of the most powerful experimental methods for the elucidation of molecular-level structures. As a noninvasive technique, NMR spectroscopy can be used for the chemical characterization of individual compounds and bulk chemical composition as well as for the examination of reaction kinetics and physicochemical properties of certain molecular domains. In environmental sciences, the application of NMR spectroscopy had a major impact on further developments as it could tackle problems and questions that previously were difficult to answer. In the following, an overview is given on how the introduction of NMR spectroscopy into Soil science altered the view about the structure of Soil Organic Matter (SOM) and the mechanisms involved in its stabilization. While former humification pathways were mainly based on the idea that monomers derived from degraded biopolymers recondensate into recalcitrant macrogeopolymers, modern concepts recognize the survival of partially degraded biopolymers because of physical and chemical protection mechanisms. Although a great deal of information was already obtained by common one-dimensional NMR techniques, advanced two-dimensional (2-D) NMR techniques are now available and first applications to geochemical samples promise to further open a door toward an improved understanding of SOM dynamics. Keywords: Soil Organic Matter characterization; NMR techniques; Soil Organic Matter structure; humification; history
