|
|
|
| Registros recuperados: 44 | |
|
|
| Thyme, Mette; Ambus, Per. |
| In organic dairy farming, a major N input to the plant-soil system comes from biological N2 fixation by pasture legumes, but knowledge is sparse on how much of the fixed N2 is lost from the pastures as N2O. Nitrifying and denitrifying bacteria are the main contributors to the N2O production in soils. Currently, no contribution from biological N2 fixation in legume pastures is included in the national N2O inventories, partly because of uncertainties in quantifying the N2 fixation in the pastures (Mosier et al., 1998). According to the guidelines issued by The Intergovernmental Panel on Climate Change (IPCC), inventories for N2O emissions from agricultural soils should be based on the assumption that 1.25 % of added N is emitted as N2O (IPCC, 1997). The... |
| Tipo: Conference paper, poster, etc. |
Palavras-chave: Nutrient turnover; Pasture and forage crops; Air and water emissions. |
| Ano: 2004 |
URL: http://orgprints.org/4147/1/4147.pdf |
| |
|
|
| 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 |
| |
|
|
| Hauggaard-Nielsen, Henrik; Ambus, Per; Brisson, Nadine; Crozat, Yves; Dahlmann, Christoph; Dibet, Audrey; von Fragstein und Niemsdorff, Peter; Gooding, Mike; Kasyanova, Elena; Launay, Marie; Monti, Michele; Pristeri, Aurelio; Steen Jensen, Erik. |
| Field pea (Pisum sativum L.) and spring barley (Hordeum vulgare L) were intercropped and sole cropped to compare the effects of crop diversity on the use of nitrogen sources in European organic crop-ping systems. Across a wide range of growing condi-tions pea-barley intercropping showed that nitrogen sources were used from 17 to 31% more efficiently by the intercrop than by the sole crops. Intercropping technologies offers the opportunity for organic cropping systems to utilize N complementarity between component crops, without compromising total crop N yield levels |
| Tipo: Conference paper, poster, etc. |
Palavras-chave: Crop combinations and interactions. |
| Ano: 2006 |
URL: http://orgprints.org/7487/1/INTERCROP_WP3_v2.pdf |
| |
|
|
| 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 |
| |
|
|
| 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 |
| |
|
| |
|
|
| 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 |
| |
|
|
| Müller-Stöver, Dorette; Hauggaard-Nielsen, Henrik; Eriksen, Jørgen; Ambus, Per; Johansen, Anders. |
| A laboratory incubation study with clover grass pasture soils of seven different ages (0, 1, 2, 3, 4, 5, and 16 production years) was carried out to determine initial soil carbon (C) and nitrogen (N) stocks and potentials for greenhouse gas emissions (N2O and CO2). Compared with the soil from the recently established pasture, an increase of total soil C and N was observed along with pasture age. Greenhouse gas emissions were low and not significantly different among the soils from younger pastures (0–5 years), but especially N2O emissions increased markedly in the soil from 16-year-old grass–clover. Low emissions might mainly be due to an early C limitation occurring in the soils from younger pastures, which was also corroborated by decreasing levels of... |
| Tipo: Journal paper |
Palavras-chave: "Organics" in general Composting and manuring Recycling; Balancing and resource management Farm nutrient management. |
| Ano: 2012 |
URL: http://orgprints.org/20915/7/20915.pdf |
| |
|
| |
|
|
| Dibet, Audrey; Hauggaard-Nielsen, Henrik; Kasyanova, Elena; Ruske, Rachel; Gooding, Mike; Pristeri, Aurelio; Monti, Michele; Dahlmann, Christoph; von Fragstein, Peter; Ambus, Per; Jensen, Erik; Crozat, Yves. |
| Two pea-barley intercropping strategies were compared with respective sole crops for their capacity to reduce weeds. Crops were grown under organic conditions without mechanical weeding. Field trials were carried out during three years throughout Europe. Although crops were tested under diverse soil and climate conditions, in the presence of different weed species and varying weed biomass, it appeared in all experimental sites that weeds were better controlled in barley sole crop or in intercrops than in pea sole crop. Differences in the degree of weed control between crop treatments were already visible at flowering and sometimes increased until maturity. It is interesting to note that the substitutive and additive designs obtained similar results. The... |
| Tipo: Conference paper, poster, etc. |
Palavras-chave: Cereals; Pulses and oilseeds Crop combinations and interactions Weed management. |
| Ano: 2006 |
URL: http://orgprints.org/7452/1/organic_congress_Dibet_Intercrop.pdf |
| |
|
|
| 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 |
| |
|
|
| Müller-Stöver, Dorette; Hauggaard-Nielsen, Henrik; Eriksen, Jørgen; Ambus, Per; Johansen, Anders. |
| A laboratory incubation study with clover grass pasture soils of six different ages (0, 1, 2, 3, 4, 5, and 16 production years) was carried out to determine initial soil carbon (C) and nitrogen (N) stocks and their effects on initial greenhouse gas (GHG) emissions (N2O and CO2) after soil incorporation of the grass-clover pastures. Compared to the soil from the recently established pasture, a significant increase of total soil C and N was observed after 2 years, which was generally increasing with pasture age. GHG emissions were not significantly different among the soils from younger pastures (0 to 5 years), but especially N2O emissions increased markedly in the soil from 16-year old grass-clover. This might mainly be due to an early carbon limitation... |
| Tipo: Journal paper |
Palavras-chave: "Organics" in general Composting and manuring Recycling; Balancing and resource management Farm nutrient management. |
| Ano: 2011 |
URL: http://orgprints.org/18978/4/18978.pdf |
| |
|
| |
|
|
| 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 |
| |
|
| |
|
|
| 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 |
| |
|
|
| Hauggaard-Nielsen, Henrik; Ambus, Per; Jensen, Erik Steen. |
| Field pea (Pisum sativum L.) and spring barley (Hordeum vulgare L) were inter- and sole cropped to compare the effects of crop diversity on productivity and use of N sources on a soil with a high weed pressure. 15N enrichment techniques were used to determine the pea-barley-weed-N dynamics. The pea-barley intercrop yielded 4.6 t grain ha-1, which was significantly greater than the yields of pea and barley in sole cropping. Calculation of Land Equivalent Ratios showed that plant growth factors were used from 25 to 38% more efficiently by the intercrop than by the sole crops. Barley sole crops accumulated 65 kg soil N ha-1 in aboveground plant parts, which was similar to 73 kg soil N ha-1 in the pea-barley intercrop and significantly greater than 15 kg soil... |
| Tipo: Journal paper |
Palavras-chave: Crop combinations and interactions Cereals; Pulses and oilseeds. |
| Ano: 2001 |
URL: http://orgprints.org/48/1/final.pdf |
| |
|
| |
|
| |
|
|
| 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 |
| |
| Registros recuperados: 44 | |
|
|
|
