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Hayo M G Van Der Werf - One of the best experts on this subject based on the ideXlab platform.
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scenario based environmental assessment of farming systems the case of pig production in france
Agriculture Ecosystems & Environment, 2005Co-Authors: Claudine Bassetmens, Hayo M G Van Der WerfAbstract:Current intensive pig production is often associated with environmental burdens. However, very few studies deal with the environmental performance of both current and alternative systems of pig production. The objectives of this study were to evaluate the environmental impacts of three contrasting pig production systems using the life cycle assessment method and to identify hot spots for each system. The scenarios compared were conventional Good Agricultural Practice (GAP) according to French production rules, a French quality label scenario called red label (RL) and a French organic scenario called organic agriculture (OA). For each of the three scenarios a “favourable” and an “unfavourable” variant was defined; these variants were used as indicators of uncertainty with respect to key parameters for technical performance and emissions of pollutants. The environmental categories assessed were: eutrophication, climate change, acidification, terrestrial toxicity, energy use, land use and pesticide use. Two functional units (FU) were used to express impacts: 1 kg of pig produced and 1 ha of land surface used. The scenarios were examined with particular emphasis on their contribution to eutrophication and acidification. Given this perspective, the RL scenario can be an interesting alternative to GAP on the condition that its emission of greenhouse gases can be reduced. The results for OA were very dependent on the choice of the FU. Per kg of pig, eutrophication and acidification were similar for OA and GAP, while OA had less eutrophication and acidification than GAP when expressed per ha. For the three scenarios, environmental hot spots and important margins of improvement were identified. Finally, the uncertainty analysis indicated that efforts should be made to produce more reliable estimations of emission factors for NO 3, NH3 and N2O in the field. © 2004 Elsevier B.V. All rights reserved.
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scenario based environmental assessment of farming systems the case of pig production in france
Agriculture Ecosystems & Environment, 2005Co-Authors: Claudine Bassetmens, Hayo M G Van Der WerfAbstract:Abstract Current intensive pig production is often associated with environmental burdens. However, very few studies deal with the environmental performance of both current and alternative systems of pig production. The objectives of this study were to evaluate the environmental impacts of three contrasting pig production systems using the life cycle assessment method and to identify hot spots for each system. The scenarios compared were conventional Good Agricultural Practice (GAP) according to French production rules, a French quality label scenario called red label (RL) and a French organic scenario called organic agriculture (OA). For each of the three scenarios a “favourable” and an “unfavourable” variant was defined; these variants were used as indicators of uncertainty with respect to key parameters for technical performance and emissions of pollutants. The environmental categories assessed were: eutrophication, climate change, acidification, terrestrial toxicity, energy use, land use and pesticide use. Two functional units (FU) were used to express impacts: 1 kg of pig produced and 1 ha of land surface used. The scenarios were examined with particular emphasis on their contribution to eutrophication and acidification. Given this perspective, the RL scenario can be an interesting alternative to GAP on the condition that its emission of greenhouse gases can be reduced. The results for OA were very dependent on the choice of the FU. Per kg of pig, eutrophication and acidification were similar for OA and GAP, while OA had less eutrophication and acidification than GAP when expressed per ha. For the three scenarios, environmental hot spots and important margins of improvement were identified. Finally, the uncertainty analysis indicated that efforts should be made to produce more reliable estimations of emission factors for NO3, NH3 and N2O in the field.
P J A Withers - One of the best experts on this subject based on the ideXlab platform.
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nutrient losses by surface run off following the application of organic manures to arable land 2 phosphorus
Environmental Pollution, 2001Co-Authors: K A Smith, D R Jackson, P J A WithersAbstract:Abstract Phosphorus (P) surface run-off losses were studied following organic manure applications to land, utilising a purpose-built facility on a sloping site in Herefordshire under arable tillage. Different rates and timing of cattle slurry, farm yard manure (FYM) and inorganic nitrogen (N) and P fertiliser were compared, over a 4-year period (1993–97). N losses from the same studies are reported in a separate paper. The application of cattle FYM and, especially slurry, to the silty clay loam soil increased both particulate and soluble P loss in surface water flow. Losses via subsurface flow (30 cm interflow) were consistently much lower than via surface water movement and were generally unaffected by treatment. Increased application of slurry solids increased all forms of P loss via surface run-off; the results suggested that a threshold for greatly increased risk of P losses via this route, as for N, occurred at ca. 2.5–3.0 t/ha solids loading. This approximates to the 50 m 3 /ha application rate limit suggested for slurry within UK ‘Good Agricultural Practice’. The studies also provided circumstantial evidence of the sealing of the soil surface by slurry solids as the major mechanism by which polluting surface run-off may occur following slurry application on susceptible soils. Losses of total and soluble P, recorded for each of the 4 years of experiments, reached a maximum of only up to 2 kg/ha total P (TP), even after slurry applications initiating run-off. Whilst these losses are insignificant in agronomic terms, peak concentrations of P (up to 30,000 μg/l TP) in surface water during a run-off event, could be of considerable concern in sensitive catchments. Losses of slurry P via surface run-off could make a significant contribution to accelerated eutrophication on entry to enclosed waters, particularly when combined with high concentrations of NO 3 − -N. Restricting slurry application rates to those consistent with Good agronomic Practice, and within the limits specified in existing guidelines on Good Agricultural Practice, offers the simplest and most effective control measure against this potentially important source of diffuse pollution.
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nutrient losses by surface run off following the application of organic manures to arable land 2 phosphorus
Environmental Pollution, 2001Co-Authors: K A Smith, D R Jackson, P J A WithersAbstract:Abstract Research was conducted on nitrogen (N) surface run-off losses following organic manure applications to land, utilising a purpose-built facility on a sloping site in Herefordshire under arable tillage. Different rates and timing of cattle slurry, farmyard manure and inorganic N and phosphorus (P) fertiliser were compared, over a 4-year period (1993–97). P losses from the same studies are reported in a separate paper. The application of cattle slurries to the silty clay loam soil increased the loss of solids and NH4+-N in surface water flow compared to control plots receiving inorganic fertiliser only, or no treatment, but had little effect on NO3−-N losses by this route. Results were consistent with other observations that rainfall events immediately after manure applications are particularly likely to be associated with nutrient run-off losses. Losses via subsurface flow (30 cm interflow) were consistently much lower than via surface water movement and were generally unaffected by treatment. Increasing slurry application rate and, in particular, slurry solids loading, increased solids and NH4+-N losses via surface run-off. The threshold, above which the risk of losses via surface run-off appeared to be greatly increased, was ca. 2.5–3.0 t/ha slurry solids, which approximates to the 50 m3/ha limit suggested for slurry within UK ‘Good Agricultural Practice’. Sealing of the soil surface by slurry solids appears to be a possible mechanism by which polluting surface run-off may occur following slurry application on susceptible soils. Total losses of NH4+-N and NO3−-N during the 4-year monitoring period were insignificant in agronomic terms, but average soluble N concentrations (NH4+-N+NO3−-N) in run-off, ranging from ca. 2.0 mg/l, up to 14.0 mg/l for the higher rate slurry treatments. Peak concentrations of NH4+-N>30 mg/l, are such as to be of concern in sensitive catchments, in terms of the potential for contribution to accelerated eutrophication and adverse effects on freshwater biota.
K A Smith - One of the best experts on this subject based on the ideXlab platform.
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strategies to encourage better use of nitrogen in animal manures
Soil Use and Management, 2006Co-Authors: B J Chambers, K A Smith, B. F. PainAbstract:Abstract. Research conducted in the MAFF Nitrate Programme has been used to formulate new and improved guidelines on the efficient use of manure nitrogen (N). In order to reduce nitrate leaching losses, manures containing large amounts of available N (i.e. slurries and poultry manures) should not be applied to free-draining soils in the period from autumn to early winter. Also, for efficient nutrient utilization manure application rates should be consistent with agronomic requirements (up to 250 kg total N ha−1 yr−1). Existing farm machinery was shown to be capable of applying manures evenly to grassland and arable stubbles, but required an accurate estimate of application rate and the careful matching of spreading widths. To provide growers with detailed guidance on the fertilizer N replacement value of manures the computer-based decision support system MANNER (MANure Nitrogen Evaluation Routine) has been developed. The much improved understanding of manure N losses and availability has been summarized in a series of ‘Managing Livestock Manures’ booklets, the MAFF Fertilizer Recommendation booklet and the Codes of Good Agricultural Practice.
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nutrient losses by surface run off following the application of organic manures to arable land 2 phosphorus
Environmental Pollution, 2001Co-Authors: K A Smith, D R Jackson, P J A WithersAbstract:Abstract Phosphorus (P) surface run-off losses were studied following organic manure applications to land, utilising a purpose-built facility on a sloping site in Herefordshire under arable tillage. Different rates and timing of cattle slurry, farm yard manure (FYM) and inorganic nitrogen (N) and P fertiliser were compared, over a 4-year period (1993–97). N losses from the same studies are reported in a separate paper. The application of cattle FYM and, especially slurry, to the silty clay loam soil increased both particulate and soluble P loss in surface water flow. Losses via subsurface flow (30 cm interflow) were consistently much lower than via surface water movement and were generally unaffected by treatment. Increased application of slurry solids increased all forms of P loss via surface run-off; the results suggested that a threshold for greatly increased risk of P losses via this route, as for N, occurred at ca. 2.5–3.0 t/ha solids loading. This approximates to the 50 m 3 /ha application rate limit suggested for slurry within UK ‘Good Agricultural Practice’. The studies also provided circumstantial evidence of the sealing of the soil surface by slurry solids as the major mechanism by which polluting surface run-off may occur following slurry application on susceptible soils. Losses of total and soluble P, recorded for each of the 4 years of experiments, reached a maximum of only up to 2 kg/ha total P (TP), even after slurry applications initiating run-off. Whilst these losses are insignificant in agronomic terms, peak concentrations of P (up to 30,000 μg/l TP) in surface water during a run-off event, could be of considerable concern in sensitive catchments. Losses of slurry P via surface run-off could make a significant contribution to accelerated eutrophication on entry to enclosed waters, particularly when combined with high concentrations of NO 3 − -N. Restricting slurry application rates to those consistent with Good agronomic Practice, and within the limits specified in existing guidelines on Good Agricultural Practice, offers the simplest and most effective control measure against this potentially important source of diffuse pollution.
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nutrient losses by surface run off following the application of organic manures to arable land 2 phosphorus
Environmental Pollution, 2001Co-Authors: K A Smith, D R Jackson, P J A WithersAbstract:Abstract Research was conducted on nitrogen (N) surface run-off losses following organic manure applications to land, utilising a purpose-built facility on a sloping site in Herefordshire under arable tillage. Different rates and timing of cattle slurry, farmyard manure and inorganic N and phosphorus (P) fertiliser were compared, over a 4-year period (1993–97). P losses from the same studies are reported in a separate paper. The application of cattle slurries to the silty clay loam soil increased the loss of solids and NH4+-N in surface water flow compared to control plots receiving inorganic fertiliser only, or no treatment, but had little effect on NO3−-N losses by this route. Results were consistent with other observations that rainfall events immediately after manure applications are particularly likely to be associated with nutrient run-off losses. Losses via subsurface flow (30 cm interflow) were consistently much lower than via surface water movement and were generally unaffected by treatment. Increasing slurry application rate and, in particular, slurry solids loading, increased solids and NH4+-N losses via surface run-off. The threshold, above which the risk of losses via surface run-off appeared to be greatly increased, was ca. 2.5–3.0 t/ha slurry solids, which approximates to the 50 m3/ha limit suggested for slurry within UK ‘Good Agricultural Practice’. Sealing of the soil surface by slurry solids appears to be a possible mechanism by which polluting surface run-off may occur following slurry application on susceptible soils. Total losses of NH4+-N and NO3−-N during the 4-year monitoring period were insignificant in agronomic terms, but average soluble N concentrations (NH4+-N+NO3−-N) in run-off, ranging from ca. 2.0 mg/l, up to 14.0 mg/l for the higher rate slurry treatments. Peak concentrations of NH4+-N>30 mg/l, are such as to be of concern in sensitive catchments, in terms of the potential for contribution to accelerated eutrophication and adverse effects on freshwater biota.
Claudine Bassetmens - One of the best experts on this subject based on the ideXlab platform.
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scenario based environmental assessment of farming systems the case of pig production in france
Agriculture Ecosystems & Environment, 2005Co-Authors: Claudine Bassetmens, Hayo M G Van Der WerfAbstract:Current intensive pig production is often associated with environmental burdens. However, very few studies deal with the environmental performance of both current and alternative systems of pig production. The objectives of this study were to evaluate the environmental impacts of three contrasting pig production systems using the life cycle assessment method and to identify hot spots for each system. The scenarios compared were conventional Good Agricultural Practice (GAP) according to French production rules, a French quality label scenario called red label (RL) and a French organic scenario called organic agriculture (OA). For each of the three scenarios a “favourable” and an “unfavourable” variant was defined; these variants were used as indicators of uncertainty with respect to key parameters for technical performance and emissions of pollutants. The environmental categories assessed were: eutrophication, climate change, acidification, terrestrial toxicity, energy use, land use and pesticide use. Two functional units (FU) were used to express impacts: 1 kg of pig produced and 1 ha of land surface used. The scenarios were examined with particular emphasis on their contribution to eutrophication and acidification. Given this perspective, the RL scenario can be an interesting alternative to GAP on the condition that its emission of greenhouse gases can be reduced. The results for OA were very dependent on the choice of the FU. Per kg of pig, eutrophication and acidification were similar for OA and GAP, while OA had less eutrophication and acidification than GAP when expressed per ha. For the three scenarios, environmental hot spots and important margins of improvement were identified. Finally, the uncertainty analysis indicated that efforts should be made to produce more reliable estimations of emission factors for NO 3, NH3 and N2O in the field. © 2004 Elsevier B.V. All rights reserved.
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scenario based environmental assessment of farming systems the case of pig production in france
Agriculture Ecosystems & Environment, 2005Co-Authors: Claudine Bassetmens, Hayo M G Van Der WerfAbstract:Abstract Current intensive pig production is often associated with environmental burdens. However, very few studies deal with the environmental performance of both current and alternative systems of pig production. The objectives of this study were to evaluate the environmental impacts of three contrasting pig production systems using the life cycle assessment method and to identify hot spots for each system. The scenarios compared were conventional Good Agricultural Practice (GAP) according to French production rules, a French quality label scenario called red label (RL) and a French organic scenario called organic agriculture (OA). For each of the three scenarios a “favourable” and an “unfavourable” variant was defined; these variants were used as indicators of uncertainty with respect to key parameters for technical performance and emissions of pollutants. The environmental categories assessed were: eutrophication, climate change, acidification, terrestrial toxicity, energy use, land use and pesticide use. Two functional units (FU) were used to express impacts: 1 kg of pig produced and 1 ha of land surface used. The scenarios were examined with particular emphasis on their contribution to eutrophication and acidification. Given this perspective, the RL scenario can be an interesting alternative to GAP on the condition that its emission of greenhouse gases can be reduced. The results for OA were very dependent on the choice of the FU. Per kg of pig, eutrophication and acidification were similar for OA and GAP, while OA had less eutrophication and acidification than GAP when expressed per ha. For the three scenarios, environmental hot spots and important margins of improvement were identified. Finally, the uncertainty analysis indicated that efforts should be made to produce more reliable estimations of emission factors for NO3, NH3 and N2O in the field.
D R Jackson - One of the best experts on this subject based on the ideXlab platform.
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nutrient losses by surface run off following the application of organic manures to arable land 2 phosphorus
Environmental Pollution, 2001Co-Authors: K A Smith, D R Jackson, P J A WithersAbstract:Abstract Phosphorus (P) surface run-off losses were studied following organic manure applications to land, utilising a purpose-built facility on a sloping site in Herefordshire under arable tillage. Different rates and timing of cattle slurry, farm yard manure (FYM) and inorganic nitrogen (N) and P fertiliser were compared, over a 4-year period (1993–97). N losses from the same studies are reported in a separate paper. The application of cattle FYM and, especially slurry, to the silty clay loam soil increased both particulate and soluble P loss in surface water flow. Losses via subsurface flow (30 cm interflow) were consistently much lower than via surface water movement and were generally unaffected by treatment. Increased application of slurry solids increased all forms of P loss via surface run-off; the results suggested that a threshold for greatly increased risk of P losses via this route, as for N, occurred at ca. 2.5–3.0 t/ha solids loading. This approximates to the 50 m 3 /ha application rate limit suggested for slurry within UK ‘Good Agricultural Practice’. The studies also provided circumstantial evidence of the sealing of the soil surface by slurry solids as the major mechanism by which polluting surface run-off may occur following slurry application on susceptible soils. Losses of total and soluble P, recorded for each of the 4 years of experiments, reached a maximum of only up to 2 kg/ha total P (TP), even after slurry applications initiating run-off. Whilst these losses are insignificant in agronomic terms, peak concentrations of P (up to 30,000 μg/l TP) in surface water during a run-off event, could be of considerable concern in sensitive catchments. Losses of slurry P via surface run-off could make a significant contribution to accelerated eutrophication on entry to enclosed waters, particularly when combined with high concentrations of NO 3 − -N. Restricting slurry application rates to those consistent with Good agronomic Practice, and within the limits specified in existing guidelines on Good Agricultural Practice, offers the simplest and most effective control measure against this potentially important source of diffuse pollution.
-
nutrient losses by surface run off following the application of organic manures to arable land 2 phosphorus
Environmental Pollution, 2001Co-Authors: K A Smith, D R Jackson, P J A WithersAbstract:Abstract Research was conducted on nitrogen (N) surface run-off losses following organic manure applications to land, utilising a purpose-built facility on a sloping site in Herefordshire under arable tillage. Different rates and timing of cattle slurry, farmyard manure and inorganic N and phosphorus (P) fertiliser were compared, over a 4-year period (1993–97). P losses from the same studies are reported in a separate paper. The application of cattle slurries to the silty clay loam soil increased the loss of solids and NH4+-N in surface water flow compared to control plots receiving inorganic fertiliser only, or no treatment, but had little effect on NO3−-N losses by this route. Results were consistent with other observations that rainfall events immediately after manure applications are particularly likely to be associated with nutrient run-off losses. Losses via subsurface flow (30 cm interflow) were consistently much lower than via surface water movement and were generally unaffected by treatment. Increasing slurry application rate and, in particular, slurry solids loading, increased solids and NH4+-N losses via surface run-off. The threshold, above which the risk of losses via surface run-off appeared to be greatly increased, was ca. 2.5–3.0 t/ha slurry solids, which approximates to the 50 m3/ha limit suggested for slurry within UK ‘Good Agricultural Practice’. Sealing of the soil surface by slurry solids appears to be a possible mechanism by which polluting surface run-off may occur following slurry application on susceptible soils. Total losses of NH4+-N and NO3−-N during the 4-year monitoring period were insignificant in agronomic terms, but average soluble N concentrations (NH4+-N+NO3−-N) in run-off, ranging from ca. 2.0 mg/l, up to 14.0 mg/l for the higher rate slurry treatments. Peak concentrations of NH4+-N>30 mg/l, are such as to be of concern in sensitive catchments, in terms of the potential for contribution to accelerated eutrophication and adverse effects on freshwater biota.