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Rui Santos - One of the best experts on this subject based on the ideXlab platform.
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carbon Nutrient Balance in relation to biomass production and halogenated compound content in the red alga asparagopsis taxiformis bonnemaisoniaceae 1
Journal of Phycology, 2012Co-Authors: Leonardo Mata, Helena Gaspar, Rui SantosAbstract:We tested how the availability of carbon and nitrogen determines both the production of Asparagopsis taxiformis (Delile) V. Trevis. and content of the two major halocarbons, bromoform and dibromoacetic acid. The halogenated secondary metabolites of Asparagopsis species are particularly interesting from an applied perspective due to their remarkable antimicrobial activity. Terrestrial ecologists named the relationship between resources and secondary metabolites as the carbon (C)/Nutrient Balance (CNB) hypothesis. This relationship was tested both in the laboratory, with a factorial analysis using different concentrations of total ammonia (TAN) and dissolved inorganic carbon (DIC), and in an integrated aquaculture system where TAN and DIC fluxes of fish effluent were manipulated. The total C/N content of A. taxiformis biomass cultivated in laboratory was highly significantly linearly related to the content of both halocarbons, as predicted by the CNB hypothesis. A. taxiformis cultivated at low levels of carbon and high levels of nitrogen (N) (lowest C/N ratio) had the lowest content in both halogenated metabolites. Increased availability of CO2 in the medium resulted in a general higher halocarbon content in the biomass, even though the effect was only statistically significant for bromoform at high levels of N. The farm experiments supported the results of the laboratory experiments. DIC fluxes had the highest effect on the production of both bromoform and biomass, as shown by multiple regression analysis. In A. taxiformis integrated aquaculture, C, rather than N, is the most important factor affecting the production of biomass and of valuable halocarbon secondary metabolites.
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CARBON/Nutrient Balance IN RELATION TO BIOMASS PRODUCTION AND HALOGENATED COMPOUND CONTENT IN THE RED ALGA ASPARAGOPSIS TAXIFORMIS (BONNEMAISONIACEAE)(1).
Journal of Phycology, 2011Co-Authors: Leonardo Mata, Helena Gaspar, Rui SantosAbstract:We tested how the availability of carbon and nitrogen determines both the production of Asparagopsis taxiformis (Delile) V. Trevis. and content of the two major halocarbons, bromoform and dibromoacetic acid. The halogenated secondary metabolites of Asparagopsis species are particularly interesting from an applied perspective due to their remarkable antimicrobial activity. Terrestrial ecologists named the relationship between resources and secondary metabolites as the carbon (C)/Nutrient Balance (CNB) hypothesis. This relationship was tested both in the laboratory, with a factorial analysis using different concentrations of total ammonia (TAN) and dissolved inorganic carbon (DIC), and in an integrated aquaculture system where TAN and DIC fluxes of fish effluent were manipulated. The total C/N content of A. taxiformis biomass cultivated in laboratory was highly significantly linearly related to the content of both halocarbons, as predicted by the CNB hypothesis. A. taxiformis cultivated at low levels of carbon and high levels of nitrogen (N) (lowest C/N ratio) had the lowest content in both halogenated metabolites. Increased availability of CO2 in the medium resulted in a general higher halocarbon content in the biomass, even though the effect was only statistically significant for bromoform at high levels of N. The farm experiments supported the results of the laboratory experiments. DIC fluxes had the highest effect on the production of both bromoform and biomass, as shown by multiple regression analysis. In A. taxiformis integrated aquaculture, C, rather than N, is the most important factor affecting the production of biomass and of valuable halocarbon secondary metabolites.
Leonardo Mata - One of the best experts on this subject based on the ideXlab platform.
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carbon Nutrient Balance in relation to biomass production and halogenated compound content in the red alga asparagopsis taxiformis bonnemaisoniaceae 1
Journal of Phycology, 2012Co-Authors: Leonardo Mata, Helena Gaspar, Rui SantosAbstract:We tested how the availability of carbon and nitrogen determines both the production of Asparagopsis taxiformis (Delile) V. Trevis. and content of the two major halocarbons, bromoform and dibromoacetic acid. The halogenated secondary metabolites of Asparagopsis species are particularly interesting from an applied perspective due to their remarkable antimicrobial activity. Terrestrial ecologists named the relationship between resources and secondary metabolites as the carbon (C)/Nutrient Balance (CNB) hypothesis. This relationship was tested both in the laboratory, with a factorial analysis using different concentrations of total ammonia (TAN) and dissolved inorganic carbon (DIC), and in an integrated aquaculture system where TAN and DIC fluxes of fish effluent were manipulated. The total C/N content of A. taxiformis biomass cultivated in laboratory was highly significantly linearly related to the content of both halocarbons, as predicted by the CNB hypothesis. A. taxiformis cultivated at low levels of carbon and high levels of nitrogen (N) (lowest C/N ratio) had the lowest content in both halogenated metabolites. Increased availability of CO2 in the medium resulted in a general higher halocarbon content in the biomass, even though the effect was only statistically significant for bromoform at high levels of N. The farm experiments supported the results of the laboratory experiments. DIC fluxes had the highest effect on the production of both bromoform and biomass, as shown by multiple regression analysis. In A. taxiformis integrated aquaculture, C, rather than N, is the most important factor affecting the production of biomass and of valuable halocarbon secondary metabolites.
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CARBON/Nutrient Balance IN RELATION TO BIOMASS PRODUCTION AND HALOGENATED COMPOUND CONTENT IN THE RED ALGA ASPARAGOPSIS TAXIFORMIS (BONNEMAISONIACEAE)(1).
Journal of Phycology, 2011Co-Authors: Leonardo Mata, Helena Gaspar, Rui SantosAbstract:We tested how the availability of carbon and nitrogen determines both the production of Asparagopsis taxiformis (Delile) V. Trevis. and content of the two major halocarbons, bromoform and dibromoacetic acid. The halogenated secondary metabolites of Asparagopsis species are particularly interesting from an applied perspective due to their remarkable antimicrobial activity. Terrestrial ecologists named the relationship between resources and secondary metabolites as the carbon (C)/Nutrient Balance (CNB) hypothesis. This relationship was tested both in the laboratory, with a factorial analysis using different concentrations of total ammonia (TAN) and dissolved inorganic carbon (DIC), and in an integrated aquaculture system where TAN and DIC fluxes of fish effluent were manipulated. The total C/N content of A. taxiformis biomass cultivated in laboratory was highly significantly linearly related to the content of both halocarbons, as predicted by the CNB hypothesis. A. taxiformis cultivated at low levels of carbon and high levels of nitrogen (N) (lowest C/N ratio) had the lowest content in both halogenated metabolites. Increased availability of CO2 in the medium resulted in a general higher halocarbon content in the biomass, even though the effect was only statistically significant for bromoform at high levels of N. The farm experiments supported the results of the laboratory experiments. DIC fluxes had the highest effect on the production of both bromoform and biomass, as shown by multiple regression analysis. In A. taxiformis integrated aquaculture, C, rather than N, is the most important factor affecting the production of biomass and of valuable halocarbon secondary metabolites.
Helena Gaspar - One of the best experts on this subject based on the ideXlab platform.
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carbon Nutrient Balance in relation to biomass production and halogenated compound content in the red alga asparagopsis taxiformis bonnemaisoniaceae 1
Journal of Phycology, 2012Co-Authors: Leonardo Mata, Helena Gaspar, Rui SantosAbstract:We tested how the availability of carbon and nitrogen determines both the production of Asparagopsis taxiformis (Delile) V. Trevis. and content of the two major halocarbons, bromoform and dibromoacetic acid. The halogenated secondary metabolites of Asparagopsis species are particularly interesting from an applied perspective due to their remarkable antimicrobial activity. Terrestrial ecologists named the relationship between resources and secondary metabolites as the carbon (C)/Nutrient Balance (CNB) hypothesis. This relationship was tested both in the laboratory, with a factorial analysis using different concentrations of total ammonia (TAN) and dissolved inorganic carbon (DIC), and in an integrated aquaculture system where TAN and DIC fluxes of fish effluent were manipulated. The total C/N content of A. taxiformis biomass cultivated in laboratory was highly significantly linearly related to the content of both halocarbons, as predicted by the CNB hypothesis. A. taxiformis cultivated at low levels of carbon and high levels of nitrogen (N) (lowest C/N ratio) had the lowest content in both halogenated metabolites. Increased availability of CO2 in the medium resulted in a general higher halocarbon content in the biomass, even though the effect was only statistically significant for bromoform at high levels of N. The farm experiments supported the results of the laboratory experiments. DIC fluxes had the highest effect on the production of both bromoform and biomass, as shown by multiple regression analysis. In A. taxiformis integrated aquaculture, C, rather than N, is the most important factor affecting the production of biomass and of valuable halocarbon secondary metabolites.
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CARBON/Nutrient Balance IN RELATION TO BIOMASS PRODUCTION AND HALOGENATED COMPOUND CONTENT IN THE RED ALGA ASPARAGOPSIS TAXIFORMIS (BONNEMAISONIACEAE)(1).
Journal of Phycology, 2011Co-Authors: Leonardo Mata, Helena Gaspar, Rui SantosAbstract:We tested how the availability of carbon and nitrogen determines both the production of Asparagopsis taxiformis (Delile) V. Trevis. and content of the two major halocarbons, bromoform and dibromoacetic acid. The halogenated secondary metabolites of Asparagopsis species are particularly interesting from an applied perspective due to their remarkable antimicrobial activity. Terrestrial ecologists named the relationship between resources and secondary metabolites as the carbon (C)/Nutrient Balance (CNB) hypothesis. This relationship was tested both in the laboratory, with a factorial analysis using different concentrations of total ammonia (TAN) and dissolved inorganic carbon (DIC), and in an integrated aquaculture system where TAN and DIC fluxes of fish effluent were manipulated. The total C/N content of A. taxiformis biomass cultivated in laboratory was highly significantly linearly related to the content of both halocarbons, as predicted by the CNB hypothesis. A. taxiformis cultivated at low levels of carbon and high levels of nitrogen (N) (lowest C/N ratio) had the lowest content in both halogenated metabolites. Increased availability of CO2 in the medium resulted in a general higher halocarbon content in the biomass, even though the effect was only statistically significant for bromoform at high levels of N. The farm experiments supported the results of the laboratory experiments. DIC fluxes had the highest effect on the production of both bromoform and biomass, as shown by multiple regression analysis. In A. taxiformis integrated aquaculture, C, rather than N, is the most important factor affecting the production of biomass and of valuable halocarbon secondary metabolites.
K. G. Cassman - One of the best experts on this subject based on the ideXlab platform.
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Fertilizer inputs, Nutrient Balance and soil Nutrient supplying power in intensive, irrigated rice system. III. Phosphorus
Nutrient Cycling in Agroecosystems, 1996Co-Authors: A. Dobermann, K. G. Cassman, P. C. Sta.cruz, M. A. A. Adviento, M. F. PampolinoAbstract:Data from long-term experiments at 11 sites in Asia with a wide range of Nutrient input treatments and yield levels were used to quantify crop P requirements of rice ( Oryza sativa L.) and the P Balance in intensive, irrigated rice systems. Uptake of 1.8–4.2 kg P was required to produce one ton of grain yield. Physiological P use efficiency varied between 220 to 900 kg grain kg P^-1. Without added P, there was a net loss of 7 to 8 kg P ha^-1 per crop; with added P there was a net gain of 4 to 5 kg P ha^-1 per crop. Phosphorus adsorption kinetics on mixed-bed ion-exchange resin capsules provided an integrative measure of soil P status, P diffusion, and acid-induced P solubilization. The resin capsule was a sensitive tool to characterize buildup or depletion of soil P as a result of different P Balances. Both Olsen-P and the resin capsule were suitable methods to predict P uptake of tropical lowland rice. It is hypothesized that both methods measure a similar soil P pool which is soluble under alkaline, aerobic conditions but transformed into acid-soluble P froms as a result of submergence and reduction. Present recommendations for P fertilizer use on rice of 20–25 kg P ha^-1 are adequate to maintain yields of 5–6 t ha^-1, but sustaining higher yields of 7–8 t ha^-1 will require farm-specific management strategies based on knowledge of the long-term P Balance and soil P-supplying capacity.
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Fertilizer inputs, Nutrient Balance, and soil Nutrient-supplying power in intensive, irrigated rice systems. I. Potassium uptake and K Balance
Nutrient Cycling in Agroecosystems, 1996Co-Authors: A. Dobermann, P. C. Sta.cruz, K. G. CassmanAbstract:Research in many countries indicates a negative K Balance in intensive, irrigated rice systems but comparative studies across different environments are few. Using a uniform sampling methodology, we measured K uptake, K use efficiency, and K Balance in six different fertilizer treatments of long-term fertility experiments with rice at 11 sites in five Asian countries. Depending on the absolute yield level, K uptake requirements of rice ranged from 17 to 30 kg K per ton of grain. For yields greater than 8 t ha^-1, total K uptake exceeded 200 kg ha^-1. The K Balance at most experimental sites was negative, with an average net removal of 34–63 kg K season^-1. There was significant depletion of soil K reserves at many sites. Based on these data, we estimated that the amount of K cycled annually from the soil into rice plants is 7–10 million t in irrigated rice systems of Asia. About 1 million t of this total amount is removed with the harvested grain. Present recommendations for K addition in most intensive irrigated rice domains are insufficient to replace K removal. However, response to K can only be expected on soils with deficient supply capacity and where other Nutrients, particularly N and P, are not limiting. Efficient K management for rice must therefore be based on the K input/output Balance, the achievable yield target, and the effective K-supplying power of the soil.
A. Dobermann - One of the best experts on this subject based on the ideXlab platform.
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Fertilizer inputs, Nutrient Balance and soil Nutrient supplying power in intensive, irrigated rice system. III. Phosphorus
Nutrient Cycling in Agroecosystems, 1996Co-Authors: A. Dobermann, K. G. Cassman, P. C. Sta.cruz, M. A. A. Adviento, M. F. PampolinoAbstract:Data from long-term experiments at 11 sites in Asia with a wide range of Nutrient input treatments and yield levels were used to quantify crop P requirements of rice ( Oryza sativa L.) and the P Balance in intensive, irrigated rice systems. Uptake of 1.8–4.2 kg P was required to produce one ton of grain yield. Physiological P use efficiency varied between 220 to 900 kg grain kg P^-1. Without added P, there was a net loss of 7 to 8 kg P ha^-1 per crop; with added P there was a net gain of 4 to 5 kg P ha^-1 per crop. Phosphorus adsorption kinetics on mixed-bed ion-exchange resin capsules provided an integrative measure of soil P status, P diffusion, and acid-induced P solubilization. The resin capsule was a sensitive tool to characterize buildup or depletion of soil P as a result of different P Balances. Both Olsen-P and the resin capsule were suitable methods to predict P uptake of tropical lowland rice. It is hypothesized that both methods measure a similar soil P pool which is soluble under alkaline, aerobic conditions but transformed into acid-soluble P froms as a result of submergence and reduction. Present recommendations for P fertilizer use on rice of 20–25 kg P ha^-1 are adequate to maintain yields of 5–6 t ha^-1, but sustaining higher yields of 7–8 t ha^-1 will require farm-specific management strategies based on knowledge of the long-term P Balance and soil P-supplying capacity.
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Fertilizer inputs, Nutrient Balance, and soil Nutrient-supplying power in intensive, irrigated rice systems. I. Potassium uptake and K Balance
Nutrient Cycling in Agroecosystems, 1996Co-Authors: A. Dobermann, P. C. Sta.cruz, K. G. CassmanAbstract:Research in many countries indicates a negative K Balance in intensive, irrigated rice systems but comparative studies across different environments are few. Using a uniform sampling methodology, we measured K uptake, K use efficiency, and K Balance in six different fertilizer treatments of long-term fertility experiments with rice at 11 sites in five Asian countries. Depending on the absolute yield level, K uptake requirements of rice ranged from 17 to 30 kg K per ton of grain. For yields greater than 8 t ha^-1, total K uptake exceeded 200 kg ha^-1. The K Balance at most experimental sites was negative, with an average net removal of 34–63 kg K season^-1. There was significant depletion of soil K reserves at many sites. Based on these data, we estimated that the amount of K cycled annually from the soil into rice plants is 7–10 million t in irrigated rice systems of Asia. About 1 million t of this total amount is removed with the harvested grain. Present recommendations for K addition in most intensive irrigated rice domains are insufficient to replace K removal. However, response to K can only be expected on soils with deficient supply capacity and where other Nutrients, particularly N and P, are not limiting. Efficient K management for rice must therefore be based on the K input/output Balance, the achievable yield target, and the effective K-supplying power of the soil.
