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Patrick Raimbault - One of the best experts on this subject based on the ideXlab platform.
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Nitrous oxide distribution and its origin in the central and eastern South Pacific Subtropical Gyre
Biogeosciences, 2007Co-Authors: J. Charpentier, L. Farias, N. Yoshida, N. Boontanon, Patrick RaimbaultAbstract:The mechanisms of microbial nitrous oxide (N2O) production in the ocean have been the subject of many discussions in recent years. New isotopomeric tools can further refine our knowledge of N2O sources in natural environments. This study compares hydrographic, N2O concentration, and N2O isotopic and isotopomeric data from three stations along a coast-perpendicular transect in the South Pacific Ocean, extending from the center (Sts. GYR and EGY) of the subtropical oligotrophic gyre (~26° S; 114° W) to the upwelling zone (St. UPX) off the central Chilean coast (~34° S). Although AOU/N2O and NO3- trends support the idea that most of the N2O (mainly from intermediate water (200–600 m)) comes from nitrification, N2O isotopomeric composition (intramolecular distribution of 15N isotopes) expressed as SP (site preference of 15N) shows low values (10 to 12\permil) that could be attributed to the production through of microbial nitrifier denitrification (reduction of nitrite to N2O mediated by ammonium oxidizers). The coincidence of this SP signal with high – stability layer, where sinking organic particles can accumulate, suggests that N2O could be produced by nitrifier denitrification inside particles. It is postulated that deceleration of particles in the pycnocline can modify the advection - diffusion balance inside particles, allowing the accumulation of nitrite and O2 depletion suitable for nitrifier denitrication. As lateral advection seems to be relatively insignificant in the gyre, in situ nitrifier denitrification could account for 40–50% of the N2O produced in this layer. In contrast, coastal upwelling system is characterized by O2 deficient condition and some N deficit in a eutrophic system. Here, N2O accumulates up to 480% saturation, and isotopic and isotopomer signals show highly complex N2O production processes, which presumably reflect both the effect of nitrification and denitrification at low O2 levels on N2O production, but net N2O consumption by denitrification was not observed.
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Nitrous oxide distribution and its origin in the central and eastern South Pacific Subtropical Gyre
Biogeosciences Discussions, 2007Co-Authors: J. Charpentier, L. Farias, N. Yoshida, N. Boontanon, Patrick RaimbaultAbstract:The biogeochemical mechanism of bacterial N2O production in the ocean has been the subject of many discussions in recent years. New isotopomeric tools can help further knowledge on N2O sources in natural environments. This research shows and compares hydrographic, nitrous oxide concentration, and N2O isotopic and isotopomeric data from three stations across the South Pacific Ocean, from the center of the subtropical oligotrophic gyre (~26° S; 114° W) to the upwelling zone along the central Chilean coast (~34° S). Althought AOU/N2O and NO3- trends support the idea that most of N2O source (mainly from intermediate water (200–1000 m)) come from nitrification, N2O isotopomeric composition (intramolecular distribution of 15N isotopes in N2O) reveals an abrupt change in the mechanism of nitrous oxide production, always observed through lower SP (site preference of 15N), at a high – stability layer, where particles could act as microsites and N2O would be produced by nitrifier denitrification (reduction of nitrite to nitrous oxide mediated by primary nitrifiers). There, nitrifier denitrification can account for 40% and 50% (center and east border of the gyre, respectively) of the nitrous oxide produced in this specific layer. This process could be associated with the deceleration of sinking organic particles in highly stable layers of the water column. In constrast, coastal upwelling system is characterized by oxygen deficient condition and some N deficit in a eutrophic system. Here, nitrous oxide accumulates up to 480% saturation, and isotopic and isotopomer signal show highly complex nitrous oxide production processes, which presumably reflect both the effect of nitrification and denitrification at low oxygen levels on N2O production, but non N2O consumption by denitrification was observed.
Septiyani Ratih - One of the best experts on this subject based on the ideXlab platform.
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EFEKTIVITAS HAMBATAN SERESAH Paraserianthes falcataria, Acacia auriculiformis, DAN Zingiber officinalis TERHADAP POTENSIAL NITRIFIKASI DAN POPULASI BAKTERI NITRIFIKASI DI TANAH ALFISOL, JUMANTONO
2008Co-Authors: Septiyani RatihAbstract:Ratih Septiyani. H 0204016. THE Effectivity Of Inhibition Paraserianthes Falcataria, Acacia Auriculiformis, And Zingiber Officinalis Litter Toward Nitrification Potential And Activity Of Nitrifying Bacteria In Alfisols, Jumantono. Nitrification in soil must be controlled, because it make inefficient nitrogen fertilizing, stimulate base cation has been leach. So it causes decrease base saturation and increase acidity in soil. Efforts to control nitrification indirectly can be achieved by control litter quality input. Litter quality will influences nitrifcation because NH4 + of the soil will be soon immobilized by heterotrof microbial during litter decomposition. The purposes of this experiment were a). to learn the effect of litter from Paraserianthes falcataria, Acacia auriculiformis, and Zingiber officinalis to Nitrifyer population and potential nitrification; b). to learn period of incubation that can inhibit nitrification; c). to learn litter quality has the strength correlation with nitrification potential. The experiment was carried out in Green House, Soil Biology Laboratory and Soil chemistry Fertility of Agriculture Faculty of Sebelas Maret University Surakarta from Juni 2007 to September 2007. This study was a functional relationship study by using Nondestructive Soil Sampling and Completed Random Design which was divided in to two factor, that is type of litter of plants and period of incubation.Type of litter of plants represent low (Acacia auriculiformis), medium (Paraserianthes falcataria), and high quality (Zingiber officinalis). Variables observation are nitrification potential, activity of the Nitrifyer microbe and heterotrophic microbe, soil pH, soil temperature, soil moisture,and soil carbon and nitrogen ratio. The data was analyzed with ANOVA F 5%, Duncan Multiple Range Test (DMRT) 5%, and correlation test. The result of the research were a). the application of litter quality of plants and period incubation have the significant effects in declining nitrification rate (Pvalue = 0.000- ). The present of low litter quality (Acacia auriculiformis) decreased nitrification potential is 76.9 %, medium litter quality (Paraserianthes falcataria) is 73.5 % and hight litter quality (Zingiber officinalis) can decreased nitrification potential is 73 %; b). The most period of incubation to inhibit nitrification potential and population of Nitrifyer bacteria in period of incubation 20th; c). The quality of litter which has straight correlation with nitrification potensial is nisbah (P+L)/N 56,3%, following lignin 54,7%. Polifenol 43,4% and the last is nisbah C/N 26,4%. Giving the litter of all plants observed in the study can decline the nitrification rate significantly so that using the litter of these plants can be recommended as an alternative way in controlling nitrification process naturally, environmental safe and supporting continuous agriculture system. Key words: Nitrification potential, Nitrifyer bacteria, Litter qualit
Ratih Septiyani - One of the best experts on this subject based on the ideXlab platform.
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Efektivitas hambatan seresah paraserianthes falcataria, acacia auriculiformis, dan zingiber officinalis terhadap potensial nitrifikasi dan populasi bakteri nitrifikasi di tanah Alfisol, Jumantono
2008Co-Authors: Ratih SeptiyaniAbstract:Ratih Septiyani. H 0204016. THE Effectivity Of Inhibition Paraserianthes Falcataria, Acacia Auriculiformis, And Zingiber Officinalis Litter Toward Nitrification Potential And Activity Of Nitrifying Bacteria In Alfisols, Jumantono. Nitrification in soil must be controlled, because it make inefficient nitrogen fertilizing, stimulate base cation has been leach. So it causes decrease base saturation and increase acidity in soil. Efforts to control nitrification indirectly can be achieved by control litter quality input. Litter quality will influences nitrifcation because NH4 + of the soil will be soon immobilized by heterotrof microbial during litter decomposition. The purposes of this experiment were a). to learn the effect of litter from Paraserianthes falcataria, Acacia auriculiformis, and Zingiber officinalis to Nitrifyer population and potential nitrification; b). to learn period of incubation that can inhibit nitrification; c). to learn litter quality has the strength correlation with nitrification potential. The experiment was carried out in Green House, Soil Biology Laboratory and Soil chemistry Fertility of Agriculture Faculty of Sebelas Maret University Surakarta from Juni 2007 to September 2007. This study was a functional relationship study by using Nondestructive Soil Sampling and Completed Random Design which was divided in to two factor, that is type of litter of plants and period of incubation.Type of litter of plants represent low (Acacia auriculiformis), medium (Paraserianthes falcataria), and high quality (Zingiber officinalis). Variables observation are nitrification potential, activity of the Nitrifyer microbe and heterotrophic microbe, soil pH, soil temperature, soil moisture,and soil carbon and nitrogen ratio. The data was analyzed with ANOVA F 5%, Duncan Multiple Range Test (DMRT) 5%, and correlation test. The result of the research were a). the application of litter quality of plants and period incubation have the significant effects in declining nitrification rate (Pvalue = 0.000- ). The present of low litter quality (Acacia auriculiformis) decreased nitrification potential is 76.9 %, medium litter quality (Paraserianthes falcataria) is 73.5 % and hight litter quality (Zingiber officinalis) can decreased nitrification potential is 73 %; b). The most period of incubation to inhibit nitrification potential and population of Nitrifyer bacteria in period of incubation 20th; c). The quality of litter which has straight correlation with nitrification potensial is nisbah (P+L)/N 56,3%, following lignin 54,7%. Polifenol 43,4% and the last is nisbah C/N 26,4%. Giving the litter of all plants observed in the study can decline the nitrification rate significantly so that using the litter of these plants can be recommended as an alternative way in controlling nitrification process naturally, environmental safe and supporting continuous agriculture system. Key words: Nitrification potential, Nitrifyer bacteria, Litter quality
J. Charpentier - One of the best experts on this subject based on the ideXlab platform.
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Nitrous oxide distribution and its origin in the central and eastern South Pacific Subtropical Gyre
Biogeosciences, 2007Co-Authors: J. Charpentier, L. Farias, N. Yoshida, N. Boontanon, Patrick RaimbaultAbstract:The mechanisms of microbial nitrous oxide (N2O) production in the ocean have been the subject of many discussions in recent years. New isotopomeric tools can further refine our knowledge of N2O sources in natural environments. This study compares hydrographic, N2O concentration, and N2O isotopic and isotopomeric data from three stations along a coast-perpendicular transect in the South Pacific Ocean, extending from the center (Sts. GYR and EGY) of the subtropical oligotrophic gyre (~26° S; 114° W) to the upwelling zone (St. UPX) off the central Chilean coast (~34° S). Although AOU/N2O and NO3- trends support the idea that most of the N2O (mainly from intermediate water (200–600 m)) comes from nitrification, N2O isotopomeric composition (intramolecular distribution of 15N isotopes) expressed as SP (site preference of 15N) shows low values (10 to 12\permil) that could be attributed to the production through of microbial nitrifier denitrification (reduction of nitrite to N2O mediated by ammonium oxidizers). The coincidence of this SP signal with high – stability layer, where sinking organic particles can accumulate, suggests that N2O could be produced by nitrifier denitrification inside particles. It is postulated that deceleration of particles in the pycnocline can modify the advection - diffusion balance inside particles, allowing the accumulation of nitrite and O2 depletion suitable for nitrifier denitrication. As lateral advection seems to be relatively insignificant in the gyre, in situ nitrifier denitrification could account for 40–50% of the N2O produced in this layer. In contrast, coastal upwelling system is characterized by O2 deficient condition and some N deficit in a eutrophic system. Here, N2O accumulates up to 480% saturation, and isotopic and isotopomer signals show highly complex N2O production processes, which presumably reflect both the effect of nitrification and denitrification at low O2 levels on N2O production, but net N2O consumption by denitrification was not observed.
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Nitrous oxide distribution and its origin in the central and eastern South Pacific Subtropical Gyre
Biogeosciences Discussions, 2007Co-Authors: J. Charpentier, L. Farias, N. Yoshida, N. Boontanon, Patrick RaimbaultAbstract:The biogeochemical mechanism of bacterial N2O production in the ocean has been the subject of many discussions in recent years. New isotopomeric tools can help further knowledge on N2O sources in natural environments. This research shows and compares hydrographic, nitrous oxide concentration, and N2O isotopic and isotopomeric data from three stations across the South Pacific Ocean, from the center of the subtropical oligotrophic gyre (~26° S; 114° W) to the upwelling zone along the central Chilean coast (~34° S). Althought AOU/N2O and NO3- trends support the idea that most of N2O source (mainly from intermediate water (200–1000 m)) come from nitrification, N2O isotopomeric composition (intramolecular distribution of 15N isotopes in N2O) reveals an abrupt change in the mechanism of nitrous oxide production, always observed through lower SP (site preference of 15N), at a high – stability layer, where particles could act as microsites and N2O would be produced by nitrifier denitrification (reduction of nitrite to nitrous oxide mediated by primary nitrifiers). There, nitrifier denitrification can account for 40% and 50% (center and east border of the gyre, respectively) of the nitrous oxide produced in this specific layer. This process could be associated with the deceleration of sinking organic particles in highly stable layers of the water column. In constrast, coastal upwelling system is characterized by oxygen deficient condition and some N deficit in a eutrophic system. Here, nitrous oxide accumulates up to 480% saturation, and isotopic and isotopomer signal show highly complex nitrous oxide production processes, which presumably reflect both the effect of nitrification and denitrification at low oxygen levels on N2O production, but non N2O consumption by denitrification was observed.
Etienne Dambrine - One of the best experts on this subject based on the ideXlab platform.
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Control of Nitrification by Tree Species in a Common-Garden Experiment
Ecosystems, 2010Co-Authors: Andrianarisoa Kasaina, Zeller Bernd, Poly Franck, Siegenfuhr Henri, Bienaimé Severine, Ranger Jacques, Etienne DambrineAbstract:We studied the effect of tree species on nitrification in five young plantations and an old native beech coppice forest at the Breuil experimental site in central France. The potential net nitrification (PNN) of soil was high in beech, Corsican pine, and Douglas fir plantations (high nitrifying stands denoted H) and low in spruce and Nordmann fir plantations as well as in native forest stands (low nitrifying stands denoted L). We hypothesized that tree species would stimulate or inhibit nitrification in transplanted soil cores within a few years after the cores were transplanted between stands. We first initiated a transplant experiment where soil cores were exchanged between all stands. The PNN remained high in soil cores from H transferred to H and low in soil cores from L transferred to L. The PNN increased considerably after 16 months in soil cores transferred from L to H, whereas the transfer of soil cores from H to L decreased the PNN only slightly after 28 months. In a second transplant experiment, forest floor material was exchanged between the Douglas fir (H) and the native forest (L) stand. Six months later, the forest floor from the native forest had increased the PNN of the Douglas fir soil considerably, whereas the forest floor from Douglas fir did not affect the PNN of the soil in the native forest stand. It was concluded that beech, Corsican pine, and Douglas fir rapidly stimulate soil nitrification by either activation of suppressed nitrifier communities and/or colonization by new nitrifier communities. Conversely, the slow and irregular reduction of nitrification in spruce, Nordmann fir, and native forest was probably due to the low and heterogeneously distributed flux of inhibiting substances per volume of soil. Our experiments suggest that the inhibition of nitrification is not tightly connected to forest floor leachates, but that the forest floor both reflects and maintains the major ongoing processes. In the long term, humus build up and the production of inhibiting substances may completely block the nitrification activity.
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Influence of tree species on gross and net N transformations in forest soils
Annals of Forest Science, 2007Co-Authors: Bernd Zeller, Sylvie Recous, Morgan Kunze, Judicaël Moukoumi, Micheline Colin-belgrand, Séverine Bienaimé, Jacques Ranger, Etienne DambrineAbstract:We compared N fluxes in a 150-year-old Fagus sylvatica coppice and five adjacent 25-year-old plantations of Fagus sylvatica, Picea abies, Quercus petraea, Pinus laricio and Pseudotsuga menziesii. We measured net N mineralization fluxes in the upper mineral horizon (A1, 0–5 cm) for 4 weeks and gross N mineralization fluxes for two days. Gross rates were measured during the 48-h period after addition of 15NH4 and 15NO3. Mineralization was measured by the 15NH4 dilution technique and gross nitrification by 15NO3 production from the addition of 15NH4, and by 15NO3 dilution. Net and gross N mineralization was lower in the soil of the old coppice, than in the plantations, both on a soil weight and organic nitrogen basis. Gross nitrification was also very low. Gross nitrification measured by NO3 dilution was slightly higher than measured by 15NO3 production from the addition of 15NH4. In the plantations, gross and net mineralization and nitrification from pool dilution were lowest in the spruce stand and highest in the beech and Corsican pine stands. We concluded that: (1) the low net mineralization in the soil of the old coppice was related to low gross rate of mineralization rather than to the concurrent effect of microbial immobilisation of mineral N; (2) the absence of nitrate in the old coppice was not related to the low rate of mineralization nor to the absence of Nitrifyers, but most probably to the inhibition of Nitrifyers in the moder humus; (3) substituting the old coppice by young stands favours Nitrifyer communities; and (4) heterotrophic Nitrifyers may bypass the ammonification step in these acid soils, but further research is needed to check this process and to characterize the microbial communities.
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Influence of tree species on gross and net N transformations in forest soils
Annals of Forest Science, 2007Co-Authors: Bernd Zeller, Sylvie Recous, Morgan Kunze, Judicaël Moukoumi, Micheline Colin-belgrand, Séverine Bienaimé, Jacques Ranger, Etienne DambrineAbstract:We compared N fluxes in a 150-year-old Fagus sylvatica coppice and five adjacent 25-year-old plantations of Fagus sylvatica, Picea abies, Quercus petraea, Pinus laricio and Pseudotsuga menziesii . We measured net N mineralization fluxes in the upper mineral horizon (A1, 0–5 cm) for 4 weeks and gross N mineralization fluxes for two days. Gross rates were measured during the 48-h period after addition of ^15NH_4 and ^15NO_3. Mineralization was measured by the ^15NH_4 dilution technique and gross nitrification by ^15NO_3 production from the addition of ^15NH_4, and by ^15NO_3 dilution. Net and gross N mineralization was lower in the soil of the old coppice, than in the plantations, both on a soil weight and organic nitrogen basis. Gross nitrification was also very low. Gross nitrification measured by NO_3 dilution was slightly higher than measured by ^15NO_3 production from the addition of ^15NH_4. In the plantations, gross and net mineralization and nitrification from pool dilution were lowest in the spruce stand and highest in the beech and Corsican pine stands. We concluded that: (1) the low net mineralization in the soil of the old coppice was related to low gross rate of mineralization rather than to the concurrent effect of microbial immobilisation of mineral N; (2) the absence of nitrate in the old coppice was not related to the low rate of mineralization nor to the absence of Nitrifyers, but most probably to the inhibition of Nitrifyers in the moder humus; (3) substituting the old coppice by young stands favours Nitrifyer communities; and (4) heterotrophic Nitrifyers may bypass the ammonification step in these acid soils, but further research is needed to check this process and to characterize the microbial communities. Nous avons mesuré les flux de minéralisation nette d’azote au cours d’une incubation de quatre semaines et les flux bruts d’azote au cours d’une incubation de deux jours dans 6 sols prélevés dans une comparaison d’espèces forestières. Nous avons comparé les horizons A1 d’un taillis sous futaie (TSF) de Fagus sylvatica et de cinq plantations adjacentes de 25 ans de Fagus sylvatica, Picea abies, Quercus petraea, Pinus laricio et Pseudotsuga menziesii . Les taux bruts ont été mesurés 48 h après l’addition de ^15NH_4, et ^15NO_3. La minéralisation brute a été calculée à partir de la dilution de ^15NH_4 et la nitrification brute à partir de la dilution de ^15NO_3 mais aussi de la production de ^15NO_3 à partir de l’apport de ^15NH_4. La minéralisation brute et nette est la plus basse dans le TSF, exprimée par gramme de sol ou d’azote organique. La nitrification nette et brute mesurée par enrichissement en ^15NO_3 est très faible, mais la nitrification brute est sensiblement plus élevée lorsqu’on l’évalue par dilution isotopique du ^15NO_3. Dans les plantations, la minéralisation et la nitrification brute et nette sont plus faibles sous épicéa et plus élevées sous hêtre et pin Laricio. Nous en concluons que (1) la faible minéralisation d’azote dans le TSF est directement liée à une faible minéralisation brute et non à l’expression d’une immobilisation microbienne de l’azote minéral formé; (2) l’absence de nitrate dans le TSF n’est pas liée à l’absence de nitrifiants mais plutôt à l’inhibition de leur activité sous le moder; (3) la coupe rase du TSF et sa plantation entraîne une levée partielle ou totale de cette inhibition; et (4) l’activité de nitrifiants hétérotrophes sans libération intermédiaire de NH_4 est possible dans ces sols acides. Des études plus approfondies devraient permettre de vérifier ce point et d’identifier ces populations.