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Iain P Mctaggart - One of the best experts on this subject based on the ideXlab platform.
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The influence of controlled release Fertilisers and the form of applied Fertiliser nitrogen on nitrous oxide emissions from an andosol
Nutrient Cycling in Agroecosystems, 2003Co-Authors: Iain P Mctaggart, Haruo TsurutaAbstract:A laboratory experiment was conducted to determine whether applying controlled release nitrogen Fertilisers could reduce nitrous oxide emissions from an andosol maintained at different water contents, compared with applying standard nitrogen Fertiliser. The effect of the form of N applied (NH4-N or NO3-N) was also investigated. Soil was collected from an arable field and sub-samples were treated with controlled release or standard Fertiliser, applied at a rate of 200 μg N g−1 dry soil either as NH4+ or NO3−. The soils were maintained at 40%, 55%, 70% or 85% water filled pore space (WFPS) and incubated at 25 °C for 50 days. Gas samples were collected and analysed every 3–4 days and soil samples were analysed on five occasions during the incubation. Emissions of N2O were much greater from ammonium sulphate than from calcium nitrate Fertiliser, indicating that nitrification was the main source of the N2O. Emissions at 85% WFPS were greater than at the lower water contents in all treatments. The use of controlled release NH4-N Fertilisers reduced and delayed the maximum peak of emissions, but at 55% and 70% WFPS this did not always result in lower total emissions. Emissions from the controlled release NO3-N Fertiliser were very low, but only significantly lower than from standard NO3-N Fertiliser at water contents below 85% WFPS. The results demonstrate that choosing the appropriate form of Fertiliser in relation to expected soil moisture could significantly reduce N2O emissions. Applying the Fertiliser in a controlled-release form could further reduce emissions by reducing the length of time that Fertiliser nitrogen is present in the soil and available for nitrification or denitrification.
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nitrous oxide emissions from grassland and spring barley following n Fertiliser application with and without nitrification inhibitors
Biology and Fertility of Soils, 1997Co-Authors: Iain P Mctaggart, H Clayton, J Parker, L A Swan, Keith SmithAbstract:The aims of this study were to assess the effectiveness of the nitrification inhibitors dicyandiamide (DCD) and nitrapyrin on reducing emissions of nitrous oxide (N2O) following application of NH4+ or NH4+-forming Fertilisers to grassland and spring barley. DCD was applied to grassland with N Fertiliser applications in April and August in 1992 and 1993, inhibiting N2O emissions by varying amounts depending on the Fertiliser form and the time of application. Over periods of up to 2 months following each application of DCD, emissions of N2O were reduced by 58–78% when applied with urea (U) and 41–65% when applied with ammonium sulphate (AS). Annual emissions (April to March) of N2O were reduced by up to 58% and 56% in 1992–1993 and 1993–1994, respectively. Applying DCD to ammonium nitrate (AN) fertilised grassland did not reduce emissions after the April 1993 fertilisation, but emissions following the August application were reduced. Nitrapyrin was only applied once, with the April Fertiliser applications in 1992, reducing N2O emissions over the following 12 months by up to 40% when applied with U. When N Fertiliser was applied in June without DCD, the DCD applied in April was still partly effective; N2O emissions were reduced 50%, 60% and 80% as effectively as the emissions following the April applications, for AS in 1993, U in 1992 and 1993, respectively. In 1992 the persistence of an inhibitory effect was greater for nitrapyrin than for DCD, increasing after the June Fertiliser application as overall emissions from U increased. There was no apparent reduction in effectiveness following repeated applications of DCD over the 2 years. N2O emissions from spring barley, measured only in 1993, were lower than from grassland. DCD reduced emissions from applied U by 40% but there was no reduction with AN. The results demonstrate considerable scope for reducing emissions by applying nitrification inhibitors with NH4+ or NH4+-forming Fertilisers; this is especially so for crops such as intensively managed grass where there are several applications of Fertiliser nitrogen per season, as the effect of inhibitors applied in April persists until after a second Fertiliser application in June.
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nitrous oxide emissions from fertilised grassland a 2 year study of the effects of n Fertiliser form and environmental conditions
Biology and Fertility of Soils, 1997Co-Authors: H Clayton, Iain P Mctaggart, J Parker, L A Swan, Keith SmithAbstract:The aim was to investigate the effects of different N Fertilisers on nitrous oxide (N2O) flux from agricultural grassland, with a view to suggesting Fertiliser practices least likely to cause substantial N2O emissions, and to assess the influence of soil and environmental factors on the emissions. Replicate plots on a clay loam grassland were fertilised with ammonium sulphate (AS), urea (U), calcium nitrate (CN), ammonium nitrate (AN), or cattle slurry supplemented with AN on three occasions in each of 2 years. Frequent measurements were made of N2O flux and soil and environmental variables. The loss of N2O-N as a percentage of N Fertiliser applied was highest from the supplemented slurry (SS) treatment and U, and lowest from AS. The temporal pattern of losses was different for the different Fertilisers and between years. Losses from U were lower than those from AN and CN in the spring, but higher in the summer. The high summer fluxes were associated with high water-filled pore space (WFPS) values. Fluxes also rose steeply with temperature where WFPS or mineral N values were not limiting. Total annual loss was higher in the 2nd year, probably because of the rainfall pattern: the percentage losses were 2.2, 1.4, 1.2, 1.1 and 0.4 from SS, U, AN, CN and AS, respectively. Application of U in the spring and AN twice in the summer in the 2nd year gave an average emission factor of 0.8% – lower than from application of either individual Fertiliser. We suggest that similar varied fertilisation practices, modified according to soil and crop type and climatic conditions, might be employed to minimise N2O emissions from agricultural land.
Keith Smith - One of the best experts on this subject based on the ideXlab platform.
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nitrous oxide emissions from grassland and spring barley following n Fertiliser application with and without nitrification inhibitors
Biology and Fertility of Soils, 1997Co-Authors: Iain P Mctaggart, H Clayton, J Parker, L A Swan, Keith SmithAbstract:The aims of this study were to assess the effectiveness of the nitrification inhibitors dicyandiamide (DCD) and nitrapyrin on reducing emissions of nitrous oxide (N2O) following application of NH4+ or NH4+-forming Fertilisers to grassland and spring barley. DCD was applied to grassland with N Fertiliser applications in April and August in 1992 and 1993, inhibiting N2O emissions by varying amounts depending on the Fertiliser form and the time of application. Over periods of up to 2 months following each application of DCD, emissions of N2O were reduced by 58–78% when applied with urea (U) and 41–65% when applied with ammonium sulphate (AS). Annual emissions (April to March) of N2O were reduced by up to 58% and 56% in 1992–1993 and 1993–1994, respectively. Applying DCD to ammonium nitrate (AN) fertilised grassland did not reduce emissions after the April 1993 fertilisation, but emissions following the August application were reduced. Nitrapyrin was only applied once, with the April Fertiliser applications in 1992, reducing N2O emissions over the following 12 months by up to 40% when applied with U. When N Fertiliser was applied in June without DCD, the DCD applied in April was still partly effective; N2O emissions were reduced 50%, 60% and 80% as effectively as the emissions following the April applications, for AS in 1993, U in 1992 and 1993, respectively. In 1992 the persistence of an inhibitory effect was greater for nitrapyrin than for DCD, increasing after the June Fertiliser application as overall emissions from U increased. There was no apparent reduction in effectiveness following repeated applications of DCD over the 2 years. N2O emissions from spring barley, measured only in 1993, were lower than from grassland. DCD reduced emissions from applied U by 40% but there was no reduction with AN. The results demonstrate considerable scope for reducing emissions by applying nitrification inhibitors with NH4+ or NH4+-forming Fertilisers; this is especially so for crops such as intensively managed grass where there are several applications of Fertiliser nitrogen per season, as the effect of inhibitors applied in April persists until after a second Fertiliser application in June.
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nitrous oxide emissions from fertilised grassland a 2 year study of the effects of n Fertiliser form and environmental conditions
Biology and Fertility of Soils, 1997Co-Authors: H Clayton, Iain P Mctaggart, J Parker, L A Swan, Keith SmithAbstract:The aim was to investigate the effects of different N Fertilisers on nitrous oxide (N2O) flux from agricultural grassland, with a view to suggesting Fertiliser practices least likely to cause substantial N2O emissions, and to assess the influence of soil and environmental factors on the emissions. Replicate plots on a clay loam grassland were fertilised with ammonium sulphate (AS), urea (U), calcium nitrate (CN), ammonium nitrate (AN), or cattle slurry supplemented with AN on three occasions in each of 2 years. Frequent measurements were made of N2O flux and soil and environmental variables. The loss of N2O-N as a percentage of N Fertiliser applied was highest from the supplemented slurry (SS) treatment and U, and lowest from AS. The temporal pattern of losses was different for the different Fertilisers and between years. Losses from U were lower than those from AN and CN in the spring, but higher in the summer. The high summer fluxes were associated with high water-filled pore space (WFPS) values. Fluxes also rose steeply with temperature where WFPS or mineral N values were not limiting. Total annual loss was higher in the 2nd year, probably because of the rainfall pattern: the percentage losses were 2.2, 1.4, 1.2, 1.1 and 0.4 from SS, U, AN, CN and AS, respectively. Application of U in the spring and AN twice in the summer in the 2nd year gave an average emission factor of 0.8% – lower than from application of either individual Fertiliser. We suggest that similar varied fertilisation practices, modified according to soil and crop type and climatic conditions, might be employed to minimise N2O emissions from agricultural land.
Haruo Tsuruta - One of the best experts on this subject based on the ideXlab platform.
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The influence of controlled release Fertilisers and the form of applied Fertiliser nitrogen on nitrous oxide emissions from an andosol
Nutrient Cycling in Agroecosystems, 2003Co-Authors: Iain P Mctaggart, Haruo TsurutaAbstract:A laboratory experiment was conducted to determine whether applying controlled release nitrogen Fertilisers could reduce nitrous oxide emissions from an andosol maintained at different water contents, compared with applying standard nitrogen Fertiliser. The effect of the form of N applied (NH4-N or NO3-N) was also investigated. Soil was collected from an arable field and sub-samples were treated with controlled release or standard Fertiliser, applied at a rate of 200 μg N g−1 dry soil either as NH4+ or NO3−. The soils were maintained at 40%, 55%, 70% or 85% water filled pore space (WFPS) and incubated at 25 °C for 50 days. Gas samples were collected and analysed every 3–4 days and soil samples were analysed on five occasions during the incubation. Emissions of N2O were much greater from ammonium sulphate than from calcium nitrate Fertiliser, indicating that nitrification was the main source of the N2O. Emissions at 85% WFPS were greater than at the lower water contents in all treatments. The use of controlled release NH4-N Fertilisers reduced and delayed the maximum peak of emissions, but at 55% and 70% WFPS this did not always result in lower total emissions. Emissions from the controlled release NO3-N Fertiliser were very low, but only significantly lower than from standard NO3-N Fertiliser at water contents below 85% WFPS. The results demonstrate that choosing the appropriate form of Fertiliser in relation to expected soil moisture could significantly reduce N2O emissions. Applying the Fertiliser in a controlled-release form could further reduce emissions by reducing the length of time that Fertiliser nitrogen is present in the soil and available for nitrification or denitrification.
Dario Sacco - One of the best experts on this subject based on the ideXlab platform.
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Conversion from mineral fertilisation to MSW compost use: Nitrogen Fertiliser value in continuous maize and test on crop rotation
The Science of the total environment, 2019Co-Authors: Barbara Moretti, Carlo Grignani, Chiara Bertora, Cristina Lerda, Luisella Celi, Dario SaccoAbstract:Abstract The recycling of agricultural wastes, co-products, and by-products is necessary for creating circular economic (closed loop) agro-food chains and more sustainable agro-ecosystems. The substitution of N mineral Fertilisers with recycled organic Fertiliser promotes a circular economy, makes the agricultural system more environmentally sustainable, and guarantees food security. Results from a continuous maize experiment and four-year rotation cropping systems (maize, winter wheat, maize, and soybean) were used in a three-year study that replaced part or all mineral Fertilisers with Municipal Solid Waste Compost (MSWC). In the first experiment, two different fertilisation strategies, MSWC only (M-Com) and mineral Fertilisers (M-Min), were compared with zero nutrients (M-Test 0), whereas in the rotation cropping systems, mineral fertilisation (R-Min) was compared with a combination of MSWC and mineral Fertilisers (R-Com + Min). Depressed yields resulted in the initial year of compost application, but by the middle term (three years), MSWC fertilisation showed a good N Fertiliser value, mainly for yield summer crops and integrated with N mineral Fertilisers. Different soil indicators and the N content in crop tissues and soil suggested that the scarce N availability recorded mainly during the first year is responsible for yield reduction. Due to limited supplies of MSWC, soil total N and the stable organic fraction bound tightly to minerals (MOM), did not vary significantly in the three-year experiment. Conversely, the more labile organic fraction (fPOM) increased only in the top soil layers (0–15 cm). Also in the top layer, M-Com increased the amount of organic fraction occluded into soil aggregates (oPOM). Furthermore, replacement of N mineral Fertiliser with compost effectively mitigated N2O emissions in wheat and maize. Overall, the Fertiliser value of MSWC was maximised when it was used repeatedly and in combination with mineral Fertiliser, especially in spring and summer crops.
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six year transition from conventional to organic farming effects on crop production and soil quality
European Journal of Agronomy, 2015Co-Authors: Dario Sacco, Arbara Moretti, Stefano Monaco, Carlo GrignaniAbstract:Abstract Organic farming has become increasingly important in recent decades as the consumer has grown its focus on the food and environmental benefits of the technique. However, when compared to conventional farming systems, organic farm system are known to yield less. Presented in this paper are the results from two organic cropping systems following six years of organic management. Fertilisation management differentiated the two systems; one was fertilised with green manure and commercial organic Fertilisers, while the other was fertilised with dairy manure. A conventional cropping system, managed with mineral Fertiliser as typical in the southern Piemonte region (Italy), served as the bussiness as usual crop management. The first hypothesis tested related to crop yield variation during the initial phase of organic management; we expected a sharp reduction in the early phase, then minor reductions later on. The second hypothesis tested related to soil fertility variation; we expected enhanced soil fertility under organic management. Overall, the organic system produced less, relative to the conventional system in interaction with year effect. Yield reduction seemed related to the lower soil nutrient availability of organic Fertilisers that provided nutrients consequent to mineralisation. Therefore, summer crops are well-suited to manure-fertilised organic farms as mineralisation happens at higher temperatures, as opposed to winter wheat, which is largely reduced in such systems. Commercial organic Fertilisers can, however, limit this effect through their high nutrient availability in the winter and early spring Also shown was that soil quality, defined as a general decrease in soil organic carbon (SOC) over time in the three analysed arable systems, can be mitigated by manure additions. Green manuring can maintain SOC and increase total N in soil, only if introduced for a sufficient number of years during crop rotation. Finally, soil fertility and Potential Mineralisable N in the different systems demonstrated that organic systems managed with commercial organic nitrogen Fertilisers and green manure do not improve soil quality, compared to systems managed with mineral Fertilisers.
Oiva Niemeläinen - One of the best experts on this subject based on the ideXlab platform.
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Yields and greenhouse gas emissions of cultivation of red clover-grass leys as assessed by LCA when fertilised with organic or mineral Fertilisers
Biomass and Bioenergy, 2012Co-Authors: Kaija Hakala, Hanna-maija Nikunen, Taija Sinkko, Oiva NiemeläinenAbstract:Abstract Red clover-grass leys incorporating three clover ( Trifolium pratense L.) varieties and two grass species, tall fescue ( Festuca arundinacea Schreb) and timothy ( Phleum pratense L.), were sown in 2003 and grown for three harvest years (2004–2006). The crops were fertilised either once with organic Fertiliser (cow manure applied in the sowing year) or yearly with mineral Fertiliser. The yields of the harvested bomasses were measured and the greenhouse gas (GHG) emissions estimated by life cycle analysis (LCA) yearly for both fertilisation types. At the end of the experiment, the carry-over effect of the red clover-grass leys was studied with spring wheat ( Triticum aestivum L.). Mineral fertilisation resulted in higher yields, but also about 2–3 times higher GHG emissions per unit clover-grass biomass than organic fertilisation. Grasses were favoured by mineral fertilisation, while the proportion of clover was higher and decreased less with time with organic fertilisation. Clover leys sown without grasses yielded least and produced the highest emissions per unit biomass. Tall fescue sown with clover produced more consistent yields than timothy, especially during drought stress and when the ley aged. Organic fertilisation appears the most sustainable way to produce field biomass for energy, at least when legumes are sown in the ley. After three years of clover-grass production, the biomass yield of spring wheat sown without Fertiliser was about 4 t ha −1 , which could augment production of biomass per parcel, and would decrease the amount of GHG emissions from bioenergy production whether fertilised with organic or mineral Fertilisers.