The Experts below are selected from a list of 255 Experts worldwide ranked by ideXlab platform
Stefan Mihai Petrea - One of the best experts on this subject based on the ideXlab platform.
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Vegetable production in an integrated aquaponic system with rainbow trout and spinach.
Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca. Animal Science and Biotechnologies, 2013Co-Authors: Stefan Mihai Petrea, Victor Cristea, Lorena Dediu, Maria Contoman, Paul Lupoae, Mirela (cretu) Mocanu, M. T. CoadăAbstract:Abstract. Background: In an integrated aquaponic system, the ratio between nitrogen production and plant assimilation is a key factor for system efficiency. That is why plant density is very important to be appropriate. Aims: The aim of this study is to expose the performances of growth parameters, both in terms of quantity and quality, for Nores variety spinach ( Spinacia oleracea ) produced in an aquaponic integrated system along with rainbow trout ( Oncorhynchus mykiss ), under three plant densities (V1 - 59 plants/m 2 , V2 - 48plants/m 2 and V3 - 39plants/m 2 ). Materials and methods: The experimental design consist in a recirculating aquaculture system with 12 growing units, mechanical and Biological Water Treatment units and four aquaponic units. Three plants densities were used (59, 48 and 39plants/m 2 ). A fish stocking density of 136fish/m 3 was used. Plants initial and final biomass was taken and a series of periodic measurements were made. Chlorophyll a, b and carotenoids, ash and dry matter were determined from spinach leaf. Results: The plant biomass gain registered good values and the quality of final plant products, given by the chlorophyll a, b , carotenoids and dry matter content were in the optimal variation interval, comparing to market spinach. Significant differences (p
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A Study of Nitrogen Cycle in an Integrated Aquaponic System with Different Plant Densities
Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca. Animal Science and Biotechnologies, 2013Co-Authors: Stefan Mihai Petrea, Victor Cristea, Lorena Dediu, Maria Contoman, Mirela (cretu) Mocanu, Alina AntacheAbstract:Introduction: There is no doubt that a fundamental element like nitrogen is one of the most important components in both animal and plants cells. Within an integrated aquaponic system, nitrogen cycle has highest priority because it converts fish wastes into nutrients for plants. Aims: The main goal of this study is to quantify the nitrogen budget for an integrated rainbow trout - spinach aquaponic system, where three plants densities were used. The second objective is to determine a balanced plant density for optimal nitrogen removal rate and hydroponic vegetable production. Materials and methods: The experimental design consist in a recirculating aquaculture system with 12 growing units, mechanical and Biological Water Treatment units and four aquaponic units. Three plants densities were used (V1 - 59plants/m 2 , V2 - 48plants/m 2 and V3 - 39plants/m 2 and a control variant V4). Fish were fed with two types of feed (41% and 50% protein), using 3 different feeding regimes. Water samples were taken and analysed by using Merck kits so that nitrate, ammonium and TAN retention rates will be observed. Water oxygen, pH and conductivity levels were also monitored. The meat, plants and faeces nitrogen content was determined by Kjeldahl method. The feed protein content was verified using the same method. Results: The amount of nitrogen removed from integrated aquaponic system through Biological filtration and also by each of the three tested spinach biomass densities was determined apart. The nitrate, ammonium and TAN retention rates, as Water passes through mechanical filter, were found to be insignificant (p>0,05), compared to ones from the Biological filter that were higher. Differences between the retention rates for each of the three variants of tested plants densities were significant higher (p
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Vegetable Production in an Integrated Aquaponic System with Rainbow Trout and Spinach
Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca. Animal Science and Biotechnologies, 2013Co-Authors: Stefan Mihai Petrea, Victor Cristea, Lorena Dediu, Maria Contoman, Paul Lupoae, Mirela (cretu) Mocanu, Marian Tiberiu CoadăAbstract:Abstract. Background: In an integrated aquaponic system, the ratio between nitrogen production and plant assimilation is a key factor for system efficiency. That is why plant density is very important to be appropriate. Aims: The aim of this study is to expose the performances of growth parameters, both in terms of quantity and quality, for Nores variety spinach ( Spinacia oleracea ) produced in an aquaponic integrated system along with rainbow trout ( Oncorhynchus mykiss ), under three plant densities (V1 - 59 plants/m 2 , V2 - 48plants/m 2 and V3 - 39plants/m 2 ). Materials and methods: The experimental design consist in a recirculating aquaculture system with 12 growing units, mechanical and Biological Water Treatment units and four aquaponic units. Three plants densities were used (59, 48 and 39plants/m 2 ). A fish stocking density of 136fish/m 3 was used. Plants initial and final biomass was taken and a series of periodic measurements were made. Chlorophyll a, b and carotenoids, ash and dry matter were determined from spinach leaf. Results: The plant biomass gain registered good values and the quality of final plant products, given by the chlorophyll a, b , carotenoids and dry matter content were in the optimal variation interval, comparing to market spinach. Significant differences (p<0.05) between variants were observed. Conclusion: In the present research work, we demonstrated that significant differences (p<0.05) were recorded in terms of growth performance between the three experimental variants and that the quality of spinach growth in an integrated aquaponic system with rainbow trout is similar to that of the market spinach.
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A Study of Nitrogen Cycle in an Integrated Aquaponic System with Different Plant Densities
Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca. Animal Science and Biotechnologies, 2013Co-Authors: Stefan Mihai Petrea, Victor Cristea, Lorena Dediu, Maria Contoman, Mirela (cretu) Mocanu, Sandita (placinta) Ion, Alina AntacheAbstract:Introduction: There is no doubt that a fundamental element like nitrogen is one of the most important components in both animal and plants cells. Within an integrated aquaponic system, nitrogen cycle has highest priority because it converts fish wastes into nutrients for plants. Aims: The main goal of this study is to quantify the nitrogen budget for an integrated rainbow trout – spinach aquaponic system, where three plants densities were used. The second objective is to determine a balanced plant density for optimal nitrogen removal rate and hydroponic vegetable production. Materials and methods: The experimental design consist in a recirculating aquaculture system with 12 growing units, mechanical and Biological Water Treatment units and four aquaponic units. Three plants densities were used (V1 - 59plants/m 2 , V2 - 48plants/m 2 and V3 - 39plants/m 2 and a control variant V4). Fish were fed with two types of feed (41% and 50% protein), using 3 different feeding regimes. Water samples were taken and analysed by using Merck kits so that nitrate, ammonium and TAN retention rates will be observed. Water oxygen, pH and conductivity levels were also monitored. The meat, plants and faeces nitrogen content was determined by Kjeldahl method. The feed protein content was verified using the same method. Results: The amount of nitrogen removed from integrated aquaponic system through Biological filtration and also by each of the three tested spinach biomass densities was determined apart. The nitrate, ammonium and TAN retention rates, as Water passes through mechanical filter, were found to be insignificant (p>0,05), compared to ones from the Biological filter that were higher. Differences between the retention rates for each of the three variants of tested plants densities were significant higher (p<0,05) at V1 compared to V3 and also higher at all three variants comparing them to the control variant. Also differences between plants nitrogen composition from V3 compared to V1 were found significant higher (p<0,05). The content of nitrogen from fish meat and fish faeces was found to be according to literature. Conclusion: In the present study, nitrate, ammonium and TAN retention rates were found to be related in a certain way with plants density and total nitrogen input in the aquaponic system, facts that also influence the plants nitrogen content. It is recommended higher plants densities to be used and also a better light intensity can be also used.
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A comparison of nitrate level in spinach grown both under different densities in aquaponic system and under natural growth conditions
Annals of the University Dunarea de Jos of Galati Fascicle VI: Food Technology, 2013Co-Authors: Stefan Mihai Petrea, Victor Cristea, Lorena Dediu, Maria Contoman, Paul Lupoae, Sandita Ion Placinta, Marian Tiberiu Coada, Mugurel EnacheAbstract:As bio-integrated systems that link both plants and fish culture, inside aquaponic systems, the processes of ammonia-oxidizing and nitrification in nitrite and nitrate are essential for growth and development of both fish and plants culture biomass. Plants with nearly the same nutritional requirements during their life cycle, like spinach in our case, are recommended to be grown under aquaponic conditions. Although nitrates concentrations up to 200 – 250mg/l are reported to be acceptable for fish growth, in the last years the toxic effect of long term exposure to high nitrate levels on fish and plants cultured biomass were highlighted. The main goal of the present study is to compare the nitrate level of spinach, grown in an aquaponic system, under three plant densities (V1 -59 plants/m 2 , V2 -48plants/m 2 and V3 – 39 plants/m 2). The second objective is to compare the results obtained, in term of nitrate content, for spinach grown in the integrated rainbow trout – spinach aquaponic system with those of marketable spinach, grown under conventional condition, in the field. The experimental design consists in a recirculating aquaculture system with 12 growing units, mechanical and Biological Water Treatment units and four aquaponic units. Fish were fed with two types of feed with 41% and 50% protein, using 3 different feeding regimes. The results show a higher nitrate level on spinach grown in aquaponic system, compared to the one derived from field culture. Differences were observed also among the three variants grown in aquaponic conditions, under different plant densities. As a conclusion, it can be said that considering the nitrate level, spinach grown in aquaponic system is marketable.
Christian Kunze - One of the best experts on this subject based on the ideXlab platform.
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MANAGEMENT OF PASSIVE Biological Water Treatment SYSTEMS FOR MINE EFFLUENTS
Advanced Science and Technology for Biological Decontamination of Sites Affected by Chemical and Radiological Nuclear Agents, 2020Co-Authors: Christian Kunze, Gunter Kieβig, Annette KüchlerAbstract:This contribution describes the approach of WISUTEC, a subsidiary of the mine remediation company WISMUT, to passive Biological Water Treatment as a long-term solution to Water contamination problems at former Uranium mining and milling sites. The paper starts with an introduction into the WISMUT project, with special emphasis on Water management and Treatment in the closure and remediation process of decommissioned mining and milling sites, and illuminates the variety of Water-related problems within this framework. One of the peculiarities of mining and milling operations in Germany and Europe in general is the relatively high population density in the affected mining areas and the scarcity of land, compared to other typical mining regions worldwide. This also leads to strict requirement with respect to the technical solutions applied in mine closure and, in particular, to restrictions on the land surface available for semi-natural and constructed wetlands. The regulatory expectations with respect to compliance with discharge standards and long-term stability are high, and command highly effective solutions on a small area. Apart from rather general aspects, the paper also highlights the practical experience from design, construction and the first years of operation of the Pohla wetland as a well-suited example. In particular, the present paper shows the pitfalls and potential problems including some realistic cost estimates which are often hidden behind the general, overoptimistic statement of "maintenance-free, zero-cost" passive Water Treatment systems.
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Management of passive Biological Water Treatment systems for mine effluents Short title: Management of Biological mine effluent Treatment systems
2020Co-Authors: Christian Kunze, Annette KüchlerAbstract:This contribution describes the approach of WISUTEC, a subsidiary of the mine remediation company WISMUT, to passive Biological Water Treatment as a long-term solution to Water contamination problems at former Uranium mining and milling sites. The paper starts with an introduction into the WISMUT project, with special emphasis on Water management and Treatment in the closure and remediation process of decommissioned mining and milling sites, and illuminates the variety of Water-related problems within this framework. One of the peculiarities of mining and milling operations in Germany and Europe in general is the relatively high population density in the affected mining areas and the scarcity of land, compared to other typical mining regions worldwide. This also leads to strict requirement with respect to the technical solutions applied in mine closure and, in particular, to restrictions on the land surface available for semi-natural and constructed wetlands. The regulatory expectations with respect to compliance with discharge standards and long-term stability are high, and command highly effective solutions on a small area. Apart from rather general aspects, the paper also highlights the practical experience from design, construction and the first years of operation of the Pohla wetland as a well-suited example.
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Long-term Stability and Resilience of Passive Mine Water Treatment Facilities: A Joint Experimental and Simulation Approach
Uranium in the Aquatic Environment, 2020Co-Authors: Christian Kunze, Franz Glombitza, André Gerth, Gunter Kiessig, Annett KüchlerAbstract:Passive Water Treatment technologies such as wetlands at abandoned mining sites are an attractive and economically sensible alternative to conventional technologies for long time-scales and relatively small contaminant loads. However, long-term stability and resilience with respect to external perturbations are a major concern for both wetland operators and regulators. In this paper, we outline a research project which addresses questions such as resilience and recovery behaviour of passive Biological Water Treatment systems.
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Passive Biological Treatment Systems of Mine Waters at WISMUT Sites
Uranium in the Environment, 2020Co-Authors: Annette Küchler, Gunter Kiessig, Christian KunzeAbstract:Water Treatment is an important component of WISMUT’s remediation activities at uranium mining and milling sites in Eastern Germany, from both an environmental and financial perspective. In most cases, uranium, radium and arsenic are the main contaminants, while at some sites, nickel and other nonradioactive metals are present too. Passive systems are an attractive alternative to conventional Treatment facilities. Numerous approaches have been developed that use natural processes to remove metallic contaminants from mine and seepage Water. However, implementing Biological Water Treatment systems is still often regarded as “tricky”, and scepticism as to their effectiveness and stability is prevalent among practitioners, the public and, perhaps most importantly, regulators. This paper addresses the regulatory and compliance issues, some of the key issues in the development and construction of such systems, and discusses practical examples of passive mine Water Treatment systems that have been completed and evaluated by WISUTEC already.
Andrey V. Dyakov - One of the best experts on this subject based on the ideXlab platform.
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WF-IoT - Biotechnology and Internet of Things for green smart city application
2016 IEEE 3rd World Forum on Internet of Things (WF-IoT), 2016Co-Authors: Pavel M. Gotovtsev, Andrey V. DyakovAbstract:This paper gives a breath overview of application of several biotechnologies in smart city and the ways of its inclusion in internet of things. Biosensors for environmental control local Biological Water Treatment systems and photobioreactors for building a discussed as a part of internet of things. Brief overview of future biotechnology that can find application in green smart city conception also presented.
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Biotechnology and Internet of Things for green smart city application
2016 IEEE 3rd World Forum on Internet of Things (WF-IoT), 2016Co-Authors: Pavel M. Gotovtsev, Andrey V. DyakovAbstract:This paper gives a breath overview of application of several biotechnologies in smart city and the ways of its inclusion in internet of things. Biosensors for environmental control local Biological Water Treatment systems and photobioreactors for building a discussed as a part of internet of things. Brief overview of future biotechnology that can find application in green smart city conception also presented.
Annette Küchler - One of the best experts on this subject based on the ideXlab platform.
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MANAGEMENT OF PASSIVE Biological Water Treatment SYSTEMS FOR MINE EFFLUENTS
Advanced Science and Technology for Biological Decontamination of Sites Affected by Chemical and Radiological Nuclear Agents, 2020Co-Authors: Christian Kunze, Gunter Kieβig, Annette KüchlerAbstract:This contribution describes the approach of WISUTEC, a subsidiary of the mine remediation company WISMUT, to passive Biological Water Treatment as a long-term solution to Water contamination problems at former Uranium mining and milling sites. The paper starts with an introduction into the WISMUT project, with special emphasis on Water management and Treatment in the closure and remediation process of decommissioned mining and milling sites, and illuminates the variety of Water-related problems within this framework. One of the peculiarities of mining and milling operations in Germany and Europe in general is the relatively high population density in the affected mining areas and the scarcity of land, compared to other typical mining regions worldwide. This also leads to strict requirement with respect to the technical solutions applied in mine closure and, in particular, to restrictions on the land surface available for semi-natural and constructed wetlands. The regulatory expectations with respect to compliance with discharge standards and long-term stability are high, and command highly effective solutions on a small area. Apart from rather general aspects, the paper also highlights the practical experience from design, construction and the first years of operation of the Pohla wetland as a well-suited example. In particular, the present paper shows the pitfalls and potential problems including some realistic cost estimates which are often hidden behind the general, overoptimistic statement of "maintenance-free, zero-cost" passive Water Treatment systems.
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Management of passive Biological Water Treatment systems for mine effluents Short title: Management of Biological mine effluent Treatment systems
2020Co-Authors: Christian Kunze, Annette KüchlerAbstract:This contribution describes the approach of WISUTEC, a subsidiary of the mine remediation company WISMUT, to passive Biological Water Treatment as a long-term solution to Water contamination problems at former Uranium mining and milling sites. The paper starts with an introduction into the WISMUT project, with special emphasis on Water management and Treatment in the closure and remediation process of decommissioned mining and milling sites, and illuminates the variety of Water-related problems within this framework. One of the peculiarities of mining and milling operations in Germany and Europe in general is the relatively high population density in the affected mining areas and the scarcity of land, compared to other typical mining regions worldwide. This also leads to strict requirement with respect to the technical solutions applied in mine closure and, in particular, to restrictions on the land surface available for semi-natural and constructed wetlands. The regulatory expectations with respect to compliance with discharge standards and long-term stability are high, and command highly effective solutions on a small area. Apart from rather general aspects, the paper also highlights the practical experience from design, construction and the first years of operation of the Pohla wetland as a well-suited example.
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Passive Biological Treatment Systems of Mine Waters at WISMUT Sites
Uranium in the Environment, 2020Co-Authors: Annette Küchler, Gunter Kiessig, Christian KunzeAbstract:Water Treatment is an important component of WISMUT’s remediation activities at uranium mining and milling sites in Eastern Germany, from both an environmental and financial perspective. In most cases, uranium, radium and arsenic are the main contaminants, while at some sites, nickel and other nonradioactive metals are present too. Passive systems are an attractive alternative to conventional Treatment facilities. Numerous approaches have been developed that use natural processes to remove metallic contaminants from mine and seepage Water. However, implementing Biological Water Treatment systems is still often regarded as “tricky”, and scepticism as to their effectiveness and stability is prevalent among practitioners, the public and, perhaps most importantly, regulators. This paper addresses the regulatory and compliance issues, some of the key issues in the development and construction of such systems, and discusses practical examples of passive mine Water Treatment systems that have been completed and evaluated by WISUTEC already.
Victor Cristea - One of the best experts on this subject based on the ideXlab platform.
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Vegetable production in an integrated aquaponic system with rainbow trout and spinach.
Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca. Animal Science and Biotechnologies, 2013Co-Authors: Stefan Mihai Petrea, Victor Cristea, Lorena Dediu, Maria Contoman, Paul Lupoae, Mirela (cretu) Mocanu, M. T. CoadăAbstract:Abstract. Background: In an integrated aquaponic system, the ratio between nitrogen production and plant assimilation is a key factor for system efficiency. That is why plant density is very important to be appropriate. Aims: The aim of this study is to expose the performances of growth parameters, both in terms of quantity and quality, for Nores variety spinach ( Spinacia oleracea ) produced in an aquaponic integrated system along with rainbow trout ( Oncorhynchus mykiss ), under three plant densities (V1 - 59 plants/m 2 , V2 - 48plants/m 2 and V3 - 39plants/m 2 ). Materials and methods: The experimental design consist in a recirculating aquaculture system with 12 growing units, mechanical and Biological Water Treatment units and four aquaponic units. Three plants densities were used (59, 48 and 39plants/m 2 ). A fish stocking density of 136fish/m 3 was used. Plants initial and final biomass was taken and a series of periodic measurements were made. Chlorophyll a, b and carotenoids, ash and dry matter were determined from spinach leaf. Results: The plant biomass gain registered good values and the quality of final plant products, given by the chlorophyll a, b , carotenoids and dry matter content were in the optimal variation interval, comparing to market spinach. Significant differences (p
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A Study of Nitrogen Cycle in an Integrated Aquaponic System with Different Plant Densities
Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca. Animal Science and Biotechnologies, 2013Co-Authors: Stefan Mihai Petrea, Victor Cristea, Lorena Dediu, Maria Contoman, Mirela (cretu) Mocanu, Alina AntacheAbstract:Introduction: There is no doubt that a fundamental element like nitrogen is one of the most important components in both animal and plants cells. Within an integrated aquaponic system, nitrogen cycle has highest priority because it converts fish wastes into nutrients for plants. Aims: The main goal of this study is to quantify the nitrogen budget for an integrated rainbow trout - spinach aquaponic system, where three plants densities were used. The second objective is to determine a balanced plant density for optimal nitrogen removal rate and hydroponic vegetable production. Materials and methods: The experimental design consist in a recirculating aquaculture system with 12 growing units, mechanical and Biological Water Treatment units and four aquaponic units. Three plants densities were used (V1 - 59plants/m 2 , V2 - 48plants/m 2 and V3 - 39plants/m 2 and a control variant V4). Fish were fed with two types of feed (41% and 50% protein), using 3 different feeding regimes. Water samples were taken and analysed by using Merck kits so that nitrate, ammonium and TAN retention rates will be observed. Water oxygen, pH and conductivity levels were also monitored. The meat, plants and faeces nitrogen content was determined by Kjeldahl method. The feed protein content was verified using the same method. Results: The amount of nitrogen removed from integrated aquaponic system through Biological filtration and also by each of the three tested spinach biomass densities was determined apart. The nitrate, ammonium and TAN retention rates, as Water passes through mechanical filter, were found to be insignificant (p>0,05), compared to ones from the Biological filter that were higher. Differences between the retention rates for each of the three variants of tested plants densities were significant higher (p
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Vegetable Production in an Integrated Aquaponic System with Rainbow Trout and Spinach
Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca. Animal Science and Biotechnologies, 2013Co-Authors: Stefan Mihai Petrea, Victor Cristea, Lorena Dediu, Maria Contoman, Paul Lupoae, Mirela (cretu) Mocanu, Marian Tiberiu CoadăAbstract:Abstract. Background: In an integrated aquaponic system, the ratio between nitrogen production and plant assimilation is a key factor for system efficiency. That is why plant density is very important to be appropriate. Aims: The aim of this study is to expose the performances of growth parameters, both in terms of quantity and quality, for Nores variety spinach ( Spinacia oleracea ) produced in an aquaponic integrated system along with rainbow trout ( Oncorhynchus mykiss ), under three plant densities (V1 - 59 plants/m 2 , V2 - 48plants/m 2 and V3 - 39plants/m 2 ). Materials and methods: The experimental design consist in a recirculating aquaculture system with 12 growing units, mechanical and Biological Water Treatment units and four aquaponic units. Three plants densities were used (59, 48 and 39plants/m 2 ). A fish stocking density of 136fish/m 3 was used. Plants initial and final biomass was taken and a series of periodic measurements were made. Chlorophyll a, b and carotenoids, ash and dry matter were determined from spinach leaf. Results: The plant biomass gain registered good values and the quality of final plant products, given by the chlorophyll a, b , carotenoids and dry matter content were in the optimal variation interval, comparing to market spinach. Significant differences (p<0.05) between variants were observed. Conclusion: In the present research work, we demonstrated that significant differences (p<0.05) were recorded in terms of growth performance between the three experimental variants and that the quality of spinach growth in an integrated aquaponic system with rainbow trout is similar to that of the market spinach.
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A Study of Nitrogen Cycle in an Integrated Aquaponic System with Different Plant Densities
Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca. Animal Science and Biotechnologies, 2013Co-Authors: Stefan Mihai Petrea, Victor Cristea, Lorena Dediu, Maria Contoman, Mirela (cretu) Mocanu, Sandita (placinta) Ion, Alina AntacheAbstract:Introduction: There is no doubt that a fundamental element like nitrogen is one of the most important components in both animal and plants cells. Within an integrated aquaponic system, nitrogen cycle has highest priority because it converts fish wastes into nutrients for plants. Aims: The main goal of this study is to quantify the nitrogen budget for an integrated rainbow trout – spinach aquaponic system, where three plants densities were used. The second objective is to determine a balanced plant density for optimal nitrogen removal rate and hydroponic vegetable production. Materials and methods: The experimental design consist in a recirculating aquaculture system with 12 growing units, mechanical and Biological Water Treatment units and four aquaponic units. Three plants densities were used (V1 - 59plants/m 2 , V2 - 48plants/m 2 and V3 - 39plants/m 2 and a control variant V4). Fish were fed with two types of feed (41% and 50% protein), using 3 different feeding regimes. Water samples were taken and analysed by using Merck kits so that nitrate, ammonium and TAN retention rates will be observed. Water oxygen, pH and conductivity levels were also monitored. The meat, plants and faeces nitrogen content was determined by Kjeldahl method. The feed protein content was verified using the same method. Results: The amount of nitrogen removed from integrated aquaponic system through Biological filtration and also by each of the three tested spinach biomass densities was determined apart. The nitrate, ammonium and TAN retention rates, as Water passes through mechanical filter, were found to be insignificant (p>0,05), compared to ones from the Biological filter that were higher. Differences between the retention rates for each of the three variants of tested plants densities were significant higher (p<0,05) at V1 compared to V3 and also higher at all three variants comparing them to the control variant. Also differences between plants nitrogen composition from V3 compared to V1 were found significant higher (p<0,05). The content of nitrogen from fish meat and fish faeces was found to be according to literature. Conclusion: In the present study, nitrate, ammonium and TAN retention rates were found to be related in a certain way with plants density and total nitrogen input in the aquaponic system, facts that also influence the plants nitrogen content. It is recommended higher plants densities to be used and also a better light intensity can be also used.
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A comparison of nitrate level in spinach grown both under different densities in aquaponic system and under natural growth conditions
Annals of the University Dunarea de Jos of Galati Fascicle VI: Food Technology, 2013Co-Authors: Stefan Mihai Petrea, Victor Cristea, Lorena Dediu, Maria Contoman, Paul Lupoae, Sandita Ion Placinta, Marian Tiberiu Coada, Mugurel EnacheAbstract:As bio-integrated systems that link both plants and fish culture, inside aquaponic systems, the processes of ammonia-oxidizing and nitrification in nitrite and nitrate are essential for growth and development of both fish and plants culture biomass. Plants with nearly the same nutritional requirements during their life cycle, like spinach in our case, are recommended to be grown under aquaponic conditions. Although nitrates concentrations up to 200 – 250mg/l are reported to be acceptable for fish growth, in the last years the toxic effect of long term exposure to high nitrate levels on fish and plants cultured biomass were highlighted. The main goal of the present study is to compare the nitrate level of spinach, grown in an aquaponic system, under three plant densities (V1 -59 plants/m 2 , V2 -48plants/m 2 and V3 – 39 plants/m 2). The second objective is to compare the results obtained, in term of nitrate content, for spinach grown in the integrated rainbow trout – spinach aquaponic system with those of marketable spinach, grown under conventional condition, in the field. The experimental design consists in a recirculating aquaculture system with 12 growing units, mechanical and Biological Water Treatment units and four aquaponic units. Fish were fed with two types of feed with 41% and 50% protein, using 3 different feeding regimes. The results show a higher nitrate level on spinach grown in aquaponic system, compared to the one derived from field culture. Differences were observed also among the three variants grown in aquaponic conditions, under different plant densities. As a conclusion, it can be said that considering the nitrate level, spinach grown in aquaponic system is marketable.
