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Registros recuperados: 40 | |
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Carter, Mette S.; Sørensen, Peter; Petersen, Søren O.; Ambus, Per. |
Organic arable farming faces challenges with low crop yields, partly due to inefficient use of green manure-derived nitrogen (N). Under current farming practices, green manure leys are often cut and mulched during the growing season with the associated risk of environmental N losses, leading to eutrophication and global warming. In this 3-month incubation experiment, we tested a new green manure management strategy as part of the ICROFS project HighCrop. With the new strategy, green manure leys are instead harvested and preserved until the following spring either as compost mixed with straw (grass-clover:straw, 4:1, w:w) or as silage of harvested ley biomass. In spring, these two green manure materials can then be used for targeted fertilization of spring... |
Tipo: Conference paper, poster, etc. |
Palavras-chave: Nutrient turnover; Air and water emissions. |
Ano: 2013 |
URL: http://orgprints.org/25941/19/25941a.pdf |
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Johansen, Anders; Carter, Mette S.; Jensen, Erik Steen; Hauggaard-Nielsen, Henrik; Ambus, Per. |
Soil from the Højbakkegård experimental (BioConcens) field was amended with nothing (control), each of two anaerobic digested (AD) materials (mixture of AD cattle manure and maize, mixture of AD cattle manure and cut off grass-clover material), raw cattle manure, and grass-clover in five individual treat-ments. The materials were incorporated homogeneously into the soil and sampled destructively at 0, 1, 3 and 9 days after incorporation. Besides, experiments were performed to follow the turnover of these materials, measured as accumulated respiration over a longer period. Measures included available organic soil carbon (cold- and hot-water extractable), soil mineral nitrogen concentration, soil pH, accumulated respiration over a two-week period, emission... |
Tipo: Journal paper |
Palavras-chave: Soil quality; Nutrient turnover; Air and water emissions; Biodiversity and ecosystem services; Farm nutrient management. |
Ano: 2011 |
URL: http://orgprints.org/18894/7/18894.pdf |
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Carter, Mette S.; Sørensen, Peter; Petersen, Søren O.; Ma, Xiuzhi; Ambus, Per. |
More efficient use of green manure-derived nitrogen (N) may improve crop yields and reduce environmental impacts in stockless organic arable farming. In this 3-month incubation study, we tested a new strategy where green manure leys are harvested and preserved until the following spring either as compost mixed with straw (grass-clover:straw, 4:1, w:w) or as silage of harvested ley biomass. Grass-clover compost or silage was soil-incorporated by either simulated ploughing (green manure placed at 15 cm depth) or harrowing (green manure mixed into the upper 5-cm soil horizon) in order to assess treatment effects on net release of plant-available N, nitrous oxide (N2O) fluxes, and soil respiration. Grass-clover silage provided the highest net N release with... |
Tipo: Journal paper |
Palavras-chave: Nutrient turnover; Air and water emissions. |
Ano: 2013 |
URL: http://orgprints.org/24960/7/24960.pdf |
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Carter, Mette S.. |
Urine deposition by grazing livestock causes an immediate increase in nitrous oxide (N2O) emissions, but the responsible mechanisms are not well understood. A nitrogen-15 (15N) labelling study was conducted in an organic grass-clover sward to examine the initial effect of urine on the rates and N2O loss ratio of nitrification (i.e. moles of N2O-N produced per moles of nitrate produced) and denitrification (i.e. moles of N2O produced per moles of N2O + N2 produced). The effect of artificial urine (52.9 g N m-2) and ammonium solution (52.9 g N m-2) was examined in separate experiments at 45 and 35% water-filled pore space (WFPS), respectively, and in each experiment a water control was included. The N2O loss derived from nitrification or denitrification was... |
Tipo: Journal paper |
Palavras-chave: Nutrient turnover; Air and water emissions; Composting and manuring. |
Ano: 2007 |
URL: http://orgprints.org/14150/1/14150.pdf |
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Carter, Mette S.; Hauggaard-Nielsen, Henrik; Johansen, Anders; Ambus, Per. |
Currently CO2 from fossil fuel combustion accounts for 57% of the global greenhouse gas emissions, whereas the strong greenhouse gases nitrous oxide (N2O) and methane (CH4) contribute with 8% and 14%, respectively (IPCC, 2007). Agricultural activity is the dominant source of N2O, which is mainly associated with the use of nitrogen based fertilizers in agricultural production. Replacing fossil fuel-derived energy by biomass-derived energy is commonly and with increasing emphasis proposed as a mean to mitigate the CO2 emissions. However, a recent analysis of global emission data proposes that accelerated emissions of N2O associated with the production of biomass for bio-fuel purposes will outweigh the avoided emissions of fossil fuel-derived CO2 (Crutzen et... |
Tipo: Conference paper, poster, etc. |
Palavras-chave: Nutrient turnover Recycling; Balancing and resource management Air and water emissions Composting and manuring. |
Ano: 2009 |
URL: http://orgprints.org/16179/1/16179.pdf |
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Johansen, Anders; Carter, Mette S.; Hauggaard-Nielsen, Henrik; Nielsen, Henrik Bangsø; Andreasen, Christian; Hansen, Christian M.; Carlsgart, Josefine; Roepstorff, Allan. |
Tipo: Conference paper, poster, etc. |
Palavras-chave: Soil quality; Nutrient turnover; Health and welfare. |
Ano: 2010 |
URL: http://orgprints.org/18902/4/18902.pdf |
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Carter, Mette S.; Sørensen, Peter; Petersen, Søren O.; Ma, Xiuzhi; Ambus, Per. |
More efficient use of green manure-derived nitrogen (N) may improve crop yields and reduce environmental impacts in stockless organic arable farming. In this 3-month incubation study, we tested a new strategy where green manure leys are harvested and preserved until the following spring either as compost mixed with straw or as silage of harvested ley biomass. Grass-clover compost or silage was soil-incorporated by either simulated ploughing (green manure placed at 15 cm depth) or harrowing (green manure mixed into the upper 5-cm soil horizon) in order to assess treatment effects on net release of plant-available N, nitrous oxide (N2O) fluxes, and soil respiration. Grass-clover silage provided the highest net N release with similar results for the two... |
Tipo: Journal paper |
Palavras-chave: Nutrient turnover; Air and water emissions. |
Ano: 2014 |
URL: http://orgprints.org/25158/7/25158.pdf |
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Johansen, Anders; Carter, Mette S.; Jensen, Erik Steen; Hauggaard-Nielsen, Henrik; Ambus, Per. |
Anaerobic digestion of animal manure and crop residues may be employed to produce biogas as a climate-neutral source of energy to provide fertilizers which allow recycling of plant nutrients on the farm. However, compared to fertilizing with the pristine input materials (e.g. raw animal slurry or plant residues), the effect on soil microbiota and soil fertility may be impacted due to the increased content of mineral nitrogen (N) and decreased amount of organic carbon (C); an issue of concern in especially organic farming systems. An incubation study was performed where 1) water, 2) raw cattle slurry, 3) anaerobically digested cattle slurry + maize, 4) anaerobically digested cattle slurry + grass-clover, or 5) fresh grass-clover was applied to soil at... |
Tipo: Journal paper |
Palavras-chave: Soil quality; Nutrient turnover; Air and water emissions; Biodiversity and ecosystem services; Farm nutrient management. |
Ano: 2011 |
URL: http://orgprints.org/20446/4/20446.pdf |
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Carter, Mette S.; Sørensen, Peter; Petersen, Søren O.; Ambus, Per. |
This 3-month incubation study showed that ensiled grass-clover was a better nitrogen (N) source than a composted grass-clover and straw mix (grass-clover:straw, 4:1, w:w), owing to the high content of labile compounds compared to the more degraded compost. Our study also indicated that emissions of the strong greenhouse gas nitrous oxide (N2O) can be reduced by incorporating green manure using harrowing instead of ploughing. The silage-derived N release by the end of the incubation was equivalent to 38-42 kg N ha-1, which corresponded to one third of the N applied in silage, with no difference between ploughing and harrowing. In contrast, no net release of mineral N was detected from the composted grass-clover. |
Tipo: Conference paper, poster, etc. |
Palavras-chave: Composting and manuring; Nutrient turnover; Air and water emissions. |
Ano: 2013 |
URL: http://orgprints.org/24520/1/24520.pdf |
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Carter, Mette S.. |
Agricultural soils are known to be a considerable source of the strong greenhouse gas nitrous oxide (N2O), and in soil N2O is mainly produced by nitrifying and denitrifying bacteria. In Denmark, grass-clover pastures are an important component of the cropping system in organic as well as conventional dairy farming, and on a European scale grass-clover mixtures represent a large part of the grazed grasslands. Biological dinitrogen (N2) fixation in clover provides a major N input to these systems, but knowledge is sparse regarding the amount of fixed N2 lost from the grasslands as N2O. Furthermore, urine patches deposited by grazing cattle are known to be hot-spots of N2O emission, but the mechanisms involved in the N2O production in urine-affected soil are... |
Tipo: Thesis |
Palavras-chave: Pasture and forage crops; Air and water emissions. |
Ano: 2005 |
URL: http://orgprints.org/10147/1/10147.pdf |
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Carter, Mette S.; Hauggaard-Nielsen, Henrik; Heiske, Stefan; Thomsen, Sune T.; Jensen, Morten; Schmidt, Jens Ejbye; Johansen, Anders; Ambus, Per. |
Field emissions of N2O during cultivation of bioenergy crops may counterbalance a considerable part of the avoided fossil CO2 emissions that are achieved by fossil fuel displacement |
Tipo: Conference paper, poster, etc. |
Palavras-chave: Nutrient turnover; Air and water emissions. |
Ano: 2011 |
URL: http://orgprints.org/18331/4/18331.pdf |
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Registros recuperados: 40 | |
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