The Experts below are selected from a list of 273 Experts worldwide ranked by ideXlab platform
Michel Loreau - One of the best experts on this subject based on the ideXlab platform.
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Biotic regulation of non-Limiting Nutrient pools and coupling of biogeochemical cycles
Ecological Modelling, 2016Co-Authors: Anne-sophie Augueres, Michel LoreauAbstract:Anthropogenic activities heavily affect biogeochemical cycles at global scales; thus it is critical to understand the degree to which these cycles can be regulated by organisms. Autotrophs can regulate Nutrient abundance through resource consumption, but their growth should not be affected by changes in the supply of non-Limiting Nutrients. Here we present a model where autotrophs consume two Nutrients one Limiting and one non-Limiting Nutrient and access only part of the Nutrients available in the environment. We apply our model to the oceanic cycles of iron and phosphorus to examine whether phytoplankton can regulate the concentrations of these key Nutrients and how interactions between the two cycles affect their regulation efficiency. Our model predicts that autotrophs cannot efficiently regulate concentrations of the non-Limiting Nutrient. We show that changes in the supply of the Limiting Nutrient affect the concentrations of the non-Limiting Nutrient, and that the two Nutrients vary in opposite directions. Our results suggest that interactions between biogeochemical cycles can result either in an increase or in a decrease in the regulation efficiency of Nutrient concentrations, depending on whether the supplies of the Limiting and non-Limiting Nutrients vary in the same or opposite directions due to anthropogenic activities. (C) 2016 Elsevier B.V. All rights reserved.
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Biotic regulation of non-Limiting Nutrient pools and coupling of biogeochemical cycles
Ecological Modelling, 2016Co-Authors: Anne-sophie Augueres, Michel LoreauAbstract:Anthropogenic activities heavily affect biogeochemical cycles at global scales; thus it is critical to understand the degree to which these cycles can be regulated by organisms. Autotrophs can regulate Nutrient abundance through resource consumption, but their growth should not be affected by changes in the supply of non-Limiting Nutrients. Here we present a model where autotrophs consume two Nutrients – one Limiting and one non-Limiting Nutrient – and access only part of the Nutrients available in the environment. We apply our model to the oceanic cycles of iron and phosphorus to examine whether phytoplankton can regulate the concentrations of these key Nutrients and how interactions between the two cycles affect their regulation efficiency. Our model predicts that autotrophs cannot efficiently regulate concentrations of the non-Limiting Nutrient. We show that changes in the supply of the Limiting Nutrient affect the concentrations of the non-Limiting Nutrient, and that the two Nutrients vary in opposite directions. Our results suggest that interactions between biogeochemical cycles can result either in an increase or in a decrease in the regulation efficiency of Nutrient concentrations, depending on whether the supplies of the Limiting and non-Limiting Nutrients vary in the same or opposite directions due to anthropogenic activities.
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When microbes and consumers determine the Limiting Nutrient of autotrophs: a theoretical analysis.
Proceedings. Biological sciences, 2008Co-Authors: Mehdi Cherif, Michel LoreauAbstract:Ecological stoichiometry postulates that differential Nutrient recycling of elements such as nitrogen and phosphorus by consumers can shift the element that limits plant growth. However, this hypothesis has so far considered the effect of consumers, mostly herbivores, out of their food-web context. Microbial decomposers are important components of food webs, and might prove as important as consumers in changing the availability of elements for plants. In this theoretical study, we investigate how decomposers determine the Nutrient that limits plants, both by feeding on Nutrients and organic carbon released by plants and consumers, and by being fed upon by omnivorous consumers. We show that decomposers can greatly alter the relative availability of Nutrients for plants. The type of Limiting Nutrient promoted by decomposers depends on their own elemental composition and, when applicable, on their ingestion by consumers. Our results highlight the limitations of previous stoichiometric theories of plant Nutrient limitation control, which often ignored trophic levels other than plants and herbivores. They also suggest that detrital chains play an important role in determining plant Nutrient limitation in many ecosystems.
Jean Louis Uribelarrea - One of the best experts on this subject based on the ideXlab platform.
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phosphorus limitation strategy to increase propionic acid flux towards 3 hydroxyvaleric acid monomers in cupriavidus necator
Bioresource Technology, 2014Co-Authors: Estelle Grousseau, Elise Blanchet, Stephane Deleris, Etienne Paul, Maria G E Albuquerque, Jean Louis UribelarreaAbstract:Abstract Properties of polyhydroxybutyrate-co-hydroxyvalerate (P(3HB-co-3HV)) depend on their 3HV content. 3HV can be produced by Cupriavidus necator from propionic acid. Few studies explored carbon distribution and dynamics of 3HV and 3HB monomers production, and none of them have been done with phosphorus as Limiting Nutrient. In this study, fed-batch cultures of C. necator with propionic acid, as sole carbon source or mixed with butyric acid, were performed. Phosphorus deficiency allowed sustaining 3HV production rate and decreasing 3HB production rate, leading to an instant production of up to 100% of 3HV. When a residual growth is sustained by a phosphorus feeding, the maximum 3HV percentage produced from propionic acid is limited to 33% (Mole.Mole −1 ). The association of a second carbon source like butyric acid lead to higher conversion of propionic acid into 3HV. This study showed the importance of the Limiting Nutrient and of the culture strategy to get the appropriate product.
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Phosphorus limitation strategy to increase propionic acid flux towards 3-hydroxyvaleric acid monomers in [i]Cupriavidus necator[/i]
Bioresource Technology, 2014Co-Authors: Estelle Grousseau, Elise Blanchet, Stephane Deleris, Etienne Paul, Maria G E Albuquerque, Jean Louis UribelarreaAbstract:Properties of polyhydroxybutyrate-co-hydroxyvalerate (P(3HB-co-3HV)) depend on their 3HV content. 3HV can be produced by [i]Cupriavidus necator[/i] from propionic acid. Few studies explored carbon distribution and dynamics of 3HV and 3HB monomers production, and none of them have been done with phosphorus as Limiting Nutrient. In this study, fed-batch cultures of [i]C. necator[/i] with propionic acid, as sole carbon source or mixed with butyric acid, were performed. Phosphorus deficiency allowed sustaining 3HV production rate and decreasing 3HB production rate, leading to an instant production of up to 100% of 3HV. When a residual growth is sustained by a phosphorus feeding, the maximum 3HV percentage produced from propionic acid is limited to 33% (Mole. Mole (1)). The association of a second carbon source like butyric acid lead to higher conversion of propionic acid into 3HV. This study showed the importance of the Limiting Nutrient and of the culture strategy to get the appropriate product.
Anne-sophie Augueres - One of the best experts on this subject based on the ideXlab platform.
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Biotic regulation of non-Limiting Nutrient pools and coupling of biogeochemical cycles
Ecological Modelling, 2016Co-Authors: Anne-sophie Augueres, Michel LoreauAbstract:Anthropogenic activities heavily affect biogeochemical cycles at global scales; thus it is critical to understand the degree to which these cycles can be regulated by organisms. Autotrophs can regulate Nutrient abundance through resource consumption, but their growth should not be affected by changes in the supply of non-Limiting Nutrients. Here we present a model where autotrophs consume two Nutrients one Limiting and one non-Limiting Nutrient and access only part of the Nutrients available in the environment. We apply our model to the oceanic cycles of iron and phosphorus to examine whether phytoplankton can regulate the concentrations of these key Nutrients and how interactions between the two cycles affect their regulation efficiency. Our model predicts that autotrophs cannot efficiently regulate concentrations of the non-Limiting Nutrient. We show that changes in the supply of the Limiting Nutrient affect the concentrations of the non-Limiting Nutrient, and that the two Nutrients vary in opposite directions. Our results suggest that interactions between biogeochemical cycles can result either in an increase or in a decrease in the regulation efficiency of Nutrient concentrations, depending on whether the supplies of the Limiting and non-Limiting Nutrients vary in the same or opposite directions due to anthropogenic activities. (C) 2016 Elsevier B.V. All rights reserved.
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Biotic regulation of non-Limiting Nutrient pools and coupling of biogeochemical cycles
Ecological Modelling, 2016Co-Authors: Anne-sophie Augueres, Michel LoreauAbstract:Anthropogenic activities heavily affect biogeochemical cycles at global scales; thus it is critical to understand the degree to which these cycles can be regulated by organisms. Autotrophs can regulate Nutrient abundance through resource consumption, but their growth should not be affected by changes in the supply of non-Limiting Nutrients. Here we present a model where autotrophs consume two Nutrients – one Limiting and one non-Limiting Nutrient – and access only part of the Nutrients available in the environment. We apply our model to the oceanic cycles of iron and phosphorus to examine whether phytoplankton can regulate the concentrations of these key Nutrients and how interactions between the two cycles affect their regulation efficiency. Our model predicts that autotrophs cannot efficiently regulate concentrations of the non-Limiting Nutrient. We show that changes in the supply of the Limiting Nutrient affect the concentrations of the non-Limiting Nutrient, and that the two Nutrients vary in opposite directions. Our results suggest that interactions between biogeochemical cycles can result either in an increase or in a decrease in the regulation efficiency of Nutrient concentrations, depending on whether the supplies of the Limiting and non-Limiting Nutrients vary in the same or opposite directions due to anthropogenic activities.
Estelle Grousseau - One of the best experts on this subject based on the ideXlab platform.
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phosphorus limitation strategy to increase propionic acid flux towards 3 hydroxyvaleric acid monomers in cupriavidus necator
Bioresource Technology, 2014Co-Authors: Estelle Grousseau, Elise Blanchet, Stephane Deleris, Etienne Paul, Maria G E Albuquerque, Jean Louis UribelarreaAbstract:Abstract Properties of polyhydroxybutyrate-co-hydroxyvalerate (P(3HB-co-3HV)) depend on their 3HV content. 3HV can be produced by Cupriavidus necator from propionic acid. Few studies explored carbon distribution and dynamics of 3HV and 3HB monomers production, and none of them have been done with phosphorus as Limiting Nutrient. In this study, fed-batch cultures of C. necator with propionic acid, as sole carbon source or mixed with butyric acid, were performed. Phosphorus deficiency allowed sustaining 3HV production rate and decreasing 3HB production rate, leading to an instant production of up to 100% of 3HV. When a residual growth is sustained by a phosphorus feeding, the maximum 3HV percentage produced from propionic acid is limited to 33% (Mole.Mole −1 ). The association of a second carbon source like butyric acid lead to higher conversion of propionic acid into 3HV. This study showed the importance of the Limiting Nutrient and of the culture strategy to get the appropriate product.
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Phosphorus limitation strategy to increase propionic acid flux towards 3-hydroxyvaleric acid monomers in [i]Cupriavidus necator[/i]
Bioresource Technology, 2014Co-Authors: Estelle Grousseau, Elise Blanchet, Stephane Deleris, Etienne Paul, Maria G E Albuquerque, Jean Louis UribelarreaAbstract:Properties of polyhydroxybutyrate-co-hydroxyvalerate (P(3HB-co-3HV)) depend on their 3HV content. 3HV can be produced by [i]Cupriavidus necator[/i] from propionic acid. Few studies explored carbon distribution and dynamics of 3HV and 3HB monomers production, and none of them have been done with phosphorus as Limiting Nutrient. In this study, fed-batch cultures of [i]C. necator[/i] with propionic acid, as sole carbon source or mixed with butyric acid, were performed. Phosphorus deficiency allowed sustaining 3HV production rate and decreasing 3HB production rate, leading to an instant production of up to 100% of 3HV. When a residual growth is sustained by a phosphorus feeding, the maximum 3HV percentage produced from propionic acid is limited to 33% (Mole. Mole (1)). The association of a second carbon source like butyric acid lead to higher conversion of propionic acid into 3HV. This study showed the importance of the Limiting Nutrient and of the culture strategy to get the appropriate product.
Etienne Paul - One of the best experts on this subject based on the ideXlab platform.
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phosphorus limitation strategy to increase propionic acid flux towards 3 hydroxyvaleric acid monomers in cupriavidus necator
Bioresource Technology, 2014Co-Authors: Estelle Grousseau, Elise Blanchet, Stephane Deleris, Etienne Paul, Maria G E Albuquerque, Jean Louis UribelarreaAbstract:Abstract Properties of polyhydroxybutyrate-co-hydroxyvalerate (P(3HB-co-3HV)) depend on their 3HV content. 3HV can be produced by Cupriavidus necator from propionic acid. Few studies explored carbon distribution and dynamics of 3HV and 3HB monomers production, and none of them have been done with phosphorus as Limiting Nutrient. In this study, fed-batch cultures of C. necator with propionic acid, as sole carbon source or mixed with butyric acid, were performed. Phosphorus deficiency allowed sustaining 3HV production rate and decreasing 3HB production rate, leading to an instant production of up to 100% of 3HV. When a residual growth is sustained by a phosphorus feeding, the maximum 3HV percentage produced from propionic acid is limited to 33% (Mole.Mole −1 ). The association of a second carbon source like butyric acid lead to higher conversion of propionic acid into 3HV. This study showed the importance of the Limiting Nutrient and of the culture strategy to get the appropriate product.
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Phosphorus limitation strategy to increase propionic acid flux towards 3-hydroxyvaleric acid monomers in [i]Cupriavidus necator[/i]
Bioresource Technology, 2014Co-Authors: Estelle Grousseau, Elise Blanchet, Stephane Deleris, Etienne Paul, Maria G E Albuquerque, Jean Louis UribelarreaAbstract:Properties of polyhydroxybutyrate-co-hydroxyvalerate (P(3HB-co-3HV)) depend on their 3HV content. 3HV can be produced by [i]Cupriavidus necator[/i] from propionic acid. Few studies explored carbon distribution and dynamics of 3HV and 3HB monomers production, and none of them have been done with phosphorus as Limiting Nutrient. In this study, fed-batch cultures of [i]C. necator[/i] with propionic acid, as sole carbon source or mixed with butyric acid, were performed. Phosphorus deficiency allowed sustaining 3HV production rate and decreasing 3HB production rate, leading to an instant production of up to 100% of 3HV. When a residual growth is sustained by a phosphorus feeding, the maximum 3HV percentage produced from propionic acid is limited to 33% (Mole. Mole (1)). The association of a second carbon source like butyric acid lead to higher conversion of propionic acid into 3HV. This study showed the importance of the Limiting Nutrient and of the culture strategy to get the appropriate product.