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Roberto Testezlaf - One of the best experts on this subject based on the ideXlab platform.
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Automated ebb-and-flow Subirrigation for citrus liners production. II. Pests, diseases and nutrient concentration
Agricultural Water Management, 2017Co-Authors: Rhuanito Soranz Ferrarezi, Roberto TestezlafAbstract:Abstract Subirrigation has the potential to reduce water and nutrients losses in citrus seedlings production by recirculating fertilizer solution (FS) and eliminating improper disposal of salts into the environment. The objectives of this study were to evaluate the effect of an automated ebb-and-flow system on pest and disease incidence and nutrient concentration of Rangpur lime ( Citrus × limonia ) liners. Nutrients were determined on plant tissue (shoot and root), substrate, and recirculated FS collected on 121-L water tanks. The treatments were four volumetric water content (VWC) to trigger Subirrigation (0.12, 0.24, 0.36 and 0.48 m 3 m −3 ), three FS concentrations (25%, 50% and 75% of the fertilizer recommendation) and a control (nursery manual overhead irrigation using breaker nozzles), arranged in a completely randomized 4 × 3 + 1 factorial plus design, with three replications. The system was automated by 39 capacitance sensors connected to a data logger, multiplexer and relay drivers, which controlled submersible pumps inside 121-L tanks with different FS. Subirrigation was turned on when VWC dropped below the set thresholds. There was occasional appearance of leaf miners ( Phyllocnistis citrella , Lepidoptera: Gracillariidae) and fungus gnats ( Bradysia sp. nr. coprophila , Diptera: Sciaridae), and no diseases (especially Xanthomonas axonopodis and Phytophthora nicotianae ). Different treatments resulted in changes on macro and micronutrients content in shoots and roots, substrate, and FS at 0, 30, 60 and 90 days ( p 0.0001). Higher FS concentrations increased the nutrient content over time ( p 0.0001). There was a decrease in pH and an increase in electric conductivity on treatments with higher VWC and FS ( p 0.0001). The substrate electric conductivity reached 5 dS m −1 twice, demanding substrate washing by water application on treatments with VWC of 0.36 and 0.48 m 3 m −3 and FS of 75%. Subirrigation is suitable for liner production in 56-cm 3 cone-shaped containers.
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Automated ebb-and-flow Subirrigation for citrus liners production. I. Plant growth
Agricultural Water Management, 2017Co-Authors: Rhuanito Soranz Ferrarezi, Roberto TestezlafAbstract:Abstract Ebb-and-flow Subirrigation is a closed system that applies water to the bottom of the containers, reducing water and nutrient losses due to recirculation of fertilizer solution (FS). The technology can improve plant growth and eliminate the improper disposal of salts into the environment. Subirrigation is widely used in the ornamental industry, and sensor-based ebb-and-flow benches can be used by the citrus nursery industry. There is a need for establishing water and fertilizer guidelines to produce citrus rootstocks. The objectives of this study were: 1) design and build an ebb-and-flow Subirrigation equipment, 2) automate the system operation using soil moisture sensors, 3) evaluate the system performance on plant growth, and 4) determine the water and fertilizer guidelines to produce Rangpur lime ( Citrus × limonia ) liners in 56-cm 3 cone-shaped containers. The treatments were four volumetric water content (VWC) to trigger Subirrigation (0.12, 0.24, 0.36 and 0.48 m 3 m −3 ), three FS concentrations (25%, 50% and 75% of the fertilizer recommendation) and a control (nursery manual overhead irrigation using breaker nozzles), arranged in a completely randomized 4 × 3 + 1 factorial plus design, with three replications. The system was automated by 39 capacitance sensors connected to a data logger, multiplexer and relay drivers, which controlled independent submersible pumps. Subirrigation was turned on when VWC dropped below the set thresholds. Sensors effectively monitored the substrate moisture and controlled Subirrigation. Treatments with highest VWC had higher substrate moisture and number of irrigations over time ( p 0.0001). The volume of water applied doubled from treatments 0.12–0.48 m 3 m −3 ( p 0.0001). Subirrigation increased shoot height, stem diameter, dry weight, leaf area, physiological parameters (leaf intracellular concentration of CO 2 , transpiration, stomatal conductance, and net photosynthesis), and water use efficiency in response to increase in VWC and FS ( p 0.0001). Subirrigation shortened the crop cycle in 30 days, anticipating the liners transplant for grafting, allowing another cultivation cycle in the nursery during the year. VWC of 0.48 m 3 m −3 and FS concentration of 50% of the recommended value for overhead irrigation are indicated for Rangpur lime liner production in 56-cm 3 containers.
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use of Subirrigation for water stress imposition in a semi continuous co2 exchange system
Ornamental Horticulture, 2015Co-Authors: Rhuanito Soranz Ferrarezi, Marc W. Van Iersel, Roberto TestezlafAbstract:The objectives of this work were to evaluate the effects of distinct moisture contents to trigger Subirrigation on salvia photosynthesis and plant growth, and to verify the feasibility of Subirrigation use in water stress imposition research in this crop. We evaluated two substrate volumetric water contents (VWC) as treatments (0.2 and 0.4 m3 m-3) to trigger Subirrigation, with 4 replications. Each replication was composed of 10 plants. An automated semi-continuous multi-chamber crop CO2-exchange system was used, with capacitance soil moisture sensors for continuous moisture monitoring. Manual Subirrigation with nutrient solution was performed when VWC dropped below the thresholds. In both treatments, the values of net photosynthesis, daily carbon gain and carbon use efficiency reduced over time, from 2 to 1.1 μmol s-1 from 2.2 to 1 μmol d-1 from 0.7 to 0.45 mol mol-1, respectively, in both soil moisture treatments. Total shoot dry mass (p=0.0129), shoot height in the tip of the highest flower (p<0.0001) and total leaf area (p=0.0007) were statistically higher at 0.4 m3 m-3 treatment. The Subirrigation system was not efficient to impose water stress, due to excessive variation on VWC values after each irrigation event in both treatments. Higher soil moisture promoted positive plant growth responses in salvia cultivated by Subirrigation.
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Use of Subirrigation for water stress imposition in a semi-continuous CO2-exchange system
Ornamental Horticulture, 2015Co-Authors: Rhuanito Soranz Ferrarezi, Marc W. Van Iersel, Roberto TestezlafAbstract:The objectives of this work were to evaluate the effects of distinct moisture contents to trigger Subirrigation on salvia photosynthesis and plant growth, and to verify the feasibility of Subirrigation use in water stress imposition research in this crop. We evaluated two substrate volumetric water contents (VWC) as treatments (0.2 and 0.4 m3 m-3) to trigger Subirrigation, with 4 replications. Each replication was composed of 10 plants. An automated semi-continuous multi-chamber crop CO2-exchange system was used, with capacitance soil moisture sensors for continuous moisture monitoring. Manual Subirrigation with nutrient solution was performed when VWC dropped below the thresholds. In both treatments, the values of net photosynthesis, daily carbon gain and carbon use efficiency reduced over time, from 2 to 1.1 μmol s-1 from 2.2 to 1 μmol d-1 from 0.7 to 0.45 mol mol-1, respectively, in both soil moisture treatments. Total shoot dry mass (p=0.0129), shoot height in the tip of the highest flower (p
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Subirrigation: Historical Overview, Challenges, and Future Prospects
HortTechnology, 2015Co-Authors: Rhuanito Soranz Ferrarezi, Geoffrey M. Weaver, Marc W. Van Iersel, Roberto TestezlafAbstract:Subirrigation is a greenhouse irrigation method that relies on capillary action to provide plants with water and nutrients from below their containers. The first documented Subirrigation system was described in 1895, and several variations on the basic design were used for research purposes before the modern ebb-and-flow type systems emerged in 1974. Most Subirrigation systems apply the fertilizer solution to a waterproof bench or greenhouse section, allowing the substrate to absorb the water through holes in the bottom of the containers. Because there is little or no leaching, Subirrigation typically allows for the use of lower fertilizer solution concentrations. Although excess fertilizer salts typically accumulate in the top layer of the substrate, this does not seem to have a negative impact on plants. Subirrigation can conserve nutrients and water, reduce labor costs, and help growers meet environmental regulations. A challenge with Subirrigation is the potential spread of pathogens via the fertilizer solution. When this is a concern, effective disinfection methods such as ultraviolet radiation, chlorine, or ozone should be used. Sensor-based irrigation control has recently been applied to Subirrigation to further improve nutrient and water use efficiencies. Better control of irrigation may help reduce the spread of pathogens, while at the same time improving crop quality. The primary economic benefit of Subirrigation is the reduction in labor costs, which is the greatest expenditure for many growers.
T. W. Welacky - One of the best experts on this subject based on the ideXlab platform.
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Influence of controlled drainage-Subirrigation on surface and tile drainage nitrate loss
Journal of Environmental Quality, 1996Co-Authors: C.f. Drury, Chin S. Tan, J.d. Gaynor, T. O. Oloya, T. W. WelackyAbstract:Controlled drainage-Subirrigation (CDS), conservation tillage, and corn (Zea mays L.) production practices were evaluated as methods of reducing NO 3 - loss through tile drainage. Controlled drainage-Subirrigation was used to manage water from precipitation and Subirrigation. Samples of tile drainage (5801) and surface runoff (3274) water were collected with autosamplers during each runoff event over a 3-yr period. Annual tile drainage volumes were reduced 24% with CDS compared with the drainage (DR) treatments. Flow weighted mean NO 3 - concentration of tile drainage water was reduced 25% from 10.6 mg N L -1 for the DR treatments to 7.9 mg N L -1 for the CDS treatments. The average annual NO 3 - loss was reduced 43% from 25.8 kg N ha -1 for the DR treatment to 14.6 kg N ha -1 for the CDS treatments. Eighty-eight to 95% of the NO 3 - losses from all treatments occurred in the noncrop period (1 Nov.-31 Apr.). Conservation tillage in combination with CDS reduced annual NO 3 - losses 49% (11.6 kg N ha -1 ) when compared with the conventional moldboard plow tillage and DR treatment. Annual NO 3 - loss through surface runoff was increased to 1.9 kg N ha -1 with the CDS treatments compared with 1.4 kg N ha -1 with the DR treatment, this loss was minor compared with losses incurred through tile drainage. Controlled drainage-Subirrigation is a technological advancement in soil and water management as it enables farmers to minimize the effect of dry summers on crop growth and reduce NO 3 - contamination of drainage water.
Rhuanito Soranz Ferrarezi - One of the best experts on this subject based on the ideXlab platform.
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automated ebb and flow Subirrigation conserves water and enhances citrus liner growth compared to capillary mat and overhead irrigation methods
Agricultural Water Management, 2021Co-Authors: Arun D Jani, Taylor D Meadows, Megan A Eckman, Rhuanito Soranz FerrareziAbstract:Abstract Most citrus nurseries in Florida, USA use overhead irrigation, but Subirrigation methods, including ebb-and-flow and capillary mats, have been shown to conserve water and accelerate plant growth relative to overhead irrigation for other nursery species and may be a viable alternative to overhead irrigation in citrus liner production. The objectives of this study were to (1) automate an ebb-and-flow system for citrus liner production using capacitance sensors, and (2) evaluate how Subirrigation and overhead irrigation methods affect water use, plant growth parameters, and substrate chemical properties. A study was conducted from 22 May to 23 September 2018 in which liners of six commercially important rootstock cultivars in cone-shaped containers were subjected to one of the following irrigation methods: ebb-and-flow triggered at substrate volumetric water contents (θ) of 0.24, 0.36, or 0.48 m3 m−3, capillary mats, and overhead irrigation. Capacitance sensors successfully monitored irrigation throughout the study. Ebb-and-flow benches used substantially less water (~411 L) than either capillary mats (13,098 L) or overhead irrigation (3193 L). By the end of the study, rootstock cultivars propagated using Subirrigation methods were approximately 22% taller with 7% more total biomass than plants subjected to overhead irrigation. Additionally, plant growth at the 0.24 m3 m−3 threshold used to trigger ebb-and-flow was as great or greater than growth at 0.36 and 0.48 m3 m−3 thresholds. During the final five weeks of the study, substrate electrical conductivity was higher using Subirrigation methods (0.84–1.3 ds m−1) than under overhead irrigation (0.55–0.8 ds m−1), but there were no symptoms of salt stress observed in plants at any time. Results from this study show that ebb-and-flow is a viable alternative to overhead irrigation and is superior to capillary mats for water conservation. In automated ebb-and-flow systems in Florida, we recommend using the 0.24 m3 m−3 threshold to produce the citrus rootstock cultivars used in this study with peat: perlite substrate.
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Automated ebb-and-flow Subirrigation for citrus liners production. I. Plant growth
Agricultural Water Management, 2017Co-Authors: Rhuanito Soranz Ferrarezi, Roberto TestezlafAbstract:Abstract Ebb-and-flow Subirrigation is a closed system that applies water to the bottom of the containers, reducing water and nutrient losses due to recirculation of fertilizer solution (FS). The technology can improve plant growth and eliminate the improper disposal of salts into the environment. Subirrigation is widely used in the ornamental industry, and sensor-based ebb-and-flow benches can be used by the citrus nursery industry. There is a need for establishing water and fertilizer guidelines to produce citrus rootstocks. The objectives of this study were: 1) design and build an ebb-and-flow Subirrigation equipment, 2) automate the system operation using soil moisture sensors, 3) evaluate the system performance on plant growth, and 4) determine the water and fertilizer guidelines to produce Rangpur lime ( Citrus × limonia ) liners in 56-cm 3 cone-shaped containers. The treatments were four volumetric water content (VWC) to trigger Subirrigation (0.12, 0.24, 0.36 and 0.48 m 3 m −3 ), three FS concentrations (25%, 50% and 75% of the fertilizer recommendation) and a control (nursery manual overhead irrigation using breaker nozzles), arranged in a completely randomized 4 × 3 + 1 factorial plus design, with three replications. The system was automated by 39 capacitance sensors connected to a data logger, multiplexer and relay drivers, which controlled independent submersible pumps. Subirrigation was turned on when VWC dropped below the set thresholds. Sensors effectively monitored the substrate moisture and controlled Subirrigation. Treatments with highest VWC had higher substrate moisture and number of irrigations over time ( p 0.0001). The volume of water applied doubled from treatments 0.12–0.48 m 3 m −3 ( p 0.0001). Subirrigation increased shoot height, stem diameter, dry weight, leaf area, physiological parameters (leaf intracellular concentration of CO 2 , transpiration, stomatal conductance, and net photosynthesis), and water use efficiency in response to increase in VWC and FS ( p 0.0001). Subirrigation shortened the crop cycle in 30 days, anticipating the liners transplant for grafting, allowing another cultivation cycle in the nursery during the year. VWC of 0.48 m 3 m −3 and FS concentration of 50% of the recommended value for overhead irrigation are indicated for Rangpur lime liner production in 56-cm 3 containers.
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Automated ebb-and-flow Subirrigation for citrus liners production. II. Pests, diseases and nutrient concentration
Agricultural Water Management, 2017Co-Authors: Rhuanito Soranz Ferrarezi, Roberto TestezlafAbstract:Abstract Subirrigation has the potential to reduce water and nutrients losses in citrus seedlings production by recirculating fertilizer solution (FS) and eliminating improper disposal of salts into the environment. The objectives of this study were to evaluate the effect of an automated ebb-and-flow system on pest and disease incidence and nutrient concentration of Rangpur lime ( Citrus × limonia ) liners. Nutrients were determined on plant tissue (shoot and root), substrate, and recirculated FS collected on 121-L water tanks. The treatments were four volumetric water content (VWC) to trigger Subirrigation (0.12, 0.24, 0.36 and 0.48 m 3 m −3 ), three FS concentrations (25%, 50% and 75% of the fertilizer recommendation) and a control (nursery manual overhead irrigation using breaker nozzles), arranged in a completely randomized 4 × 3 + 1 factorial plus design, with three replications. The system was automated by 39 capacitance sensors connected to a data logger, multiplexer and relay drivers, which controlled submersible pumps inside 121-L tanks with different FS. Subirrigation was turned on when VWC dropped below the set thresholds. There was occasional appearance of leaf miners ( Phyllocnistis citrella , Lepidoptera: Gracillariidae) and fungus gnats ( Bradysia sp. nr. coprophila , Diptera: Sciaridae), and no diseases (especially Xanthomonas axonopodis and Phytophthora nicotianae ). Different treatments resulted in changes on macro and micronutrients content in shoots and roots, substrate, and FS at 0, 30, 60 and 90 days ( p 0.0001). Higher FS concentrations increased the nutrient content over time ( p 0.0001). There was a decrease in pH and an increase in electric conductivity on treatments with higher VWC and FS ( p 0.0001). The substrate electric conductivity reached 5 dS m −1 twice, demanding substrate washing by water application on treatments with VWC of 0.36 and 0.48 m 3 m −3 and FS of 75%. Subirrigation is suitable for liner production in 56-cm 3 cone-shaped containers.
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use of Subirrigation for water stress imposition in a semi continuous co2 exchange system
Ornamental Horticulture, 2015Co-Authors: Rhuanito Soranz Ferrarezi, Marc W. Van Iersel, Roberto TestezlafAbstract:The objectives of this work were to evaluate the effects of distinct moisture contents to trigger Subirrigation on salvia photosynthesis and plant growth, and to verify the feasibility of Subirrigation use in water stress imposition research in this crop. We evaluated two substrate volumetric water contents (VWC) as treatments (0.2 and 0.4 m3 m-3) to trigger Subirrigation, with 4 replications. Each replication was composed of 10 plants. An automated semi-continuous multi-chamber crop CO2-exchange system was used, with capacitance soil moisture sensors for continuous moisture monitoring. Manual Subirrigation with nutrient solution was performed when VWC dropped below the thresholds. In both treatments, the values of net photosynthesis, daily carbon gain and carbon use efficiency reduced over time, from 2 to 1.1 μmol s-1 from 2.2 to 1 μmol d-1 from 0.7 to 0.45 mol mol-1, respectively, in both soil moisture treatments. Total shoot dry mass (p=0.0129), shoot height in the tip of the highest flower (p<0.0001) and total leaf area (p=0.0007) were statistically higher at 0.4 m3 m-3 treatment. The Subirrigation system was not efficient to impose water stress, due to excessive variation on VWC values after each irrigation event in both treatments. Higher soil moisture promoted positive plant growth responses in salvia cultivated by Subirrigation.
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Use of Subirrigation for water stress imposition in a semi-continuous CO2-exchange system
Ornamental Horticulture, 2015Co-Authors: Rhuanito Soranz Ferrarezi, Marc W. Van Iersel, Roberto TestezlafAbstract:The objectives of this work were to evaluate the effects of distinct moisture contents to trigger Subirrigation on salvia photosynthesis and plant growth, and to verify the feasibility of Subirrigation use in water stress imposition research in this crop. We evaluated two substrate volumetric water contents (VWC) as treatments (0.2 and 0.4 m3 m-3) to trigger Subirrigation, with 4 replications. Each replication was composed of 10 plants. An automated semi-continuous multi-chamber crop CO2-exchange system was used, with capacitance soil moisture sensors for continuous moisture monitoring. Manual Subirrigation with nutrient solution was performed when VWC dropped below the thresholds. In both treatments, the values of net photosynthesis, daily carbon gain and carbon use efficiency reduced over time, from 2 to 1.1 μmol s-1 from 2.2 to 1 μmol d-1 from 0.7 to 0.45 mol mol-1, respectively, in both soil moisture treatments. Total shoot dry mass (p=0.0129), shoot height in the tip of the highest flower (p
C.f. Drury - One of the best experts on this subject based on the ideXlab platform.
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EFFECT OF CONTROLLED DRAINAGE AND Subirrigation ON SUBSURFACE TILE DRAINAGE NITRATE LOSS AND CROP YIELD AT THE FARM SCALE
Canadian Water Resources Journal, 1999Co-Authors: Chin S. Tan, C.f. Drury, J.d. GaynorAbstract:An on-farm evaluation of controlled drainage and Subirrigation systems can raise farmer awareness and acceptance of these innovative technologies. A four hectare field experiment was established on sandy-loam soil near Harrow in Essex County, Ontario. The field was modified to allow the implementation of two water table-management treatments, controlled drainage with Subirrigation (CDS) and free outlet tile drainage (DR). Volume of tile drainage, nitrate concentration and loss in the tile drainage water and crop yields were measured. The objectives of the study were to provide on-farm demonstrations of controlled drainage and Subirrigation systems, and to determine their effect on crop yields and environmental benefits.The CDS system reduced flow weighted mean nitrate concentration in tile drainage water by 38% and total nitrate loss by 37% compared to the DR system from May 1995 to April 1997. The CDS system increased marketable tomato yields by 11% in 1995. The average marketable tomato yields were 58.4...
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Influence of controlled drainage-Subirrigation on surface and tile drainage nitrate loss
Journal of Environmental Quality, 1996Co-Authors: C.f. Drury, Chin S. Tan, J.d. Gaynor, T. O. Oloya, T. W. WelackyAbstract:Controlled drainage-Subirrigation (CDS), conservation tillage, and corn (Zea mays L.) production practices were evaluated as methods of reducing NO 3 - loss through tile drainage. Controlled drainage-Subirrigation was used to manage water from precipitation and Subirrigation. Samples of tile drainage (5801) and surface runoff (3274) water were collected with autosamplers during each runoff event over a 3-yr period. Annual tile drainage volumes were reduced 24% with CDS compared with the drainage (DR) treatments. Flow weighted mean NO 3 - concentration of tile drainage water was reduced 25% from 10.6 mg N L -1 for the DR treatments to 7.9 mg N L -1 for the CDS treatments. The average annual NO 3 - loss was reduced 43% from 25.8 kg N ha -1 for the DR treatment to 14.6 kg N ha -1 for the CDS treatments. Eighty-eight to 95% of the NO 3 - losses from all treatments occurred in the noncrop period (1 Nov.-31 Apr.). Conservation tillage in combination with CDS reduced annual NO 3 - losses 49% (11.6 kg N ha -1 ) when compared with the conventional moldboard plow tillage and DR treatment. Annual NO 3 - loss through surface runoff was increased to 1.9 kg N ha -1 with the CDS treatments compared with 1.4 kg N ha -1 with the DR treatment, this loss was minor compared with losses incurred through tile drainage. Controlled drainage-Subirrigation is a technological advancement in soil and water management as it enables farmers to minimize the effect of dry summers on crop growth and reduce NO 3 - contamination of drainage water.
J.d. Gaynor - One of the best experts on this subject based on the ideXlab platform.
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EFFECT OF CONTROLLED DRAINAGE AND Subirrigation ON SUBSURFACE TILE DRAINAGE NITRATE LOSS AND CROP YIELD AT THE FARM SCALE
Canadian Water Resources Journal, 1999Co-Authors: Chin S. Tan, C.f. Drury, J.d. GaynorAbstract:An on-farm evaluation of controlled drainage and Subirrigation systems can raise farmer awareness and acceptance of these innovative technologies. A four hectare field experiment was established on sandy-loam soil near Harrow in Essex County, Ontario. The field was modified to allow the implementation of two water table-management treatments, controlled drainage with Subirrigation (CDS) and free outlet tile drainage (DR). Volume of tile drainage, nitrate concentration and loss in the tile drainage water and crop yields were measured. The objectives of the study were to provide on-farm demonstrations of controlled drainage and Subirrigation systems, and to determine their effect on crop yields and environmental benefits.The CDS system reduced flow weighted mean nitrate concentration in tile drainage water by 38% and total nitrate loss by 37% compared to the DR system from May 1995 to April 1997. The CDS system increased marketable tomato yields by 11% in 1995. The average marketable tomato yields were 58.4...
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Influence of controlled drainage-Subirrigation on surface and tile drainage nitrate loss
Journal of Environmental Quality, 1996Co-Authors: C.f. Drury, Chin S. Tan, J.d. Gaynor, T. O. Oloya, T. W. WelackyAbstract:Controlled drainage-Subirrigation (CDS), conservation tillage, and corn (Zea mays L.) production practices were evaluated as methods of reducing NO 3 - loss through tile drainage. Controlled drainage-Subirrigation was used to manage water from precipitation and Subirrigation. Samples of tile drainage (5801) and surface runoff (3274) water were collected with autosamplers during each runoff event over a 3-yr period. Annual tile drainage volumes were reduced 24% with CDS compared with the drainage (DR) treatments. Flow weighted mean NO 3 - concentration of tile drainage water was reduced 25% from 10.6 mg N L -1 for the DR treatments to 7.9 mg N L -1 for the CDS treatments. The average annual NO 3 - loss was reduced 43% from 25.8 kg N ha -1 for the DR treatment to 14.6 kg N ha -1 for the CDS treatments. Eighty-eight to 95% of the NO 3 - losses from all treatments occurred in the noncrop period (1 Nov.-31 Apr.). Conservation tillage in combination with CDS reduced annual NO 3 - losses 49% (11.6 kg N ha -1 ) when compared with the conventional moldboard plow tillage and DR treatment. Annual NO 3 - loss through surface runoff was increased to 1.9 kg N ha -1 with the CDS treatments compared with 1.4 kg N ha -1 with the DR treatment, this loss was minor compared with losses incurred through tile drainage. Controlled drainage-Subirrigation is a technological advancement in soil and water management as it enables farmers to minimize the effect of dry summers on crop growth and reduce NO 3 - contamination of drainage water.
