Consulta: creatorFacets:"Petersen, Søren O."
Registros recuperados: 27
Data/hora: 02/06/2024 16:41:37

Effects of C and N availability and soil-water potential interactions on N2O evolution and PLFA composition
Provedor de dados: 21
Autores: Andersen, Astrid J.; Petersen, Søren O.
Mitigation of agricultural N2O emissions via management requires quantitative information about the regulation of the underlying processes. In this laboratory study. short-term evolution of N2O from repacked soil was determined using an arable sandy loam soil adjusted to three water potentials (-15,-30 or -100 hPa) that were reached by adjustment of partly air-dried soil with nutrient solutions or water; a water retention curve of repacked soil had been determined prior to the incubation experiment. The amendments included a control treatment receiving water (CTL), and aqueous solutions of carbon in the form of glucose (C). ammonium sulfate (N), or both (CN). Rates Of CO2 and N2O evolution were followed during 14 days. Soil inorganic N and phospholipid...
Tipo: Journal paper
Palavras-chave: Environmental aspects; Soil.
Ano: 2009
URL: http://orgprints.org/16097/2/16097.pdf

Short-term nitrous oxide emissions from pasture soil as influenced by urea level and soil nitrate
Provedor de dados: 21
Autores: Petersen, Søren O.; Stamatiadis, Stamatis; Christofides, Calliopi.
Nitrogen excreted by cattle during grazing is a significant source of atmospheric nitrous oxide (N2O). The regulation of N2O emissions is not well understood, but may vary with urine composition and soil conditions. This laboratory study was undertaken to describe short-term effects on N2O emissions and soil conditions, including microbial dynamics, of urea amendment at two different rates (22 and 43 g N m-2). The lower urea concentration was also combined with an elevated soil NO3- concentration. Urea solutions labelled with 25 atom% 15N were added to the surface of repacked pasture soil cores and incubated for 1, 3, 6 or 9 days under constant conditions (60% WFPS, 14°C). Soil inorganic N (NH4+, NO2- and NO3-), pH, electrical conductivity and dissolved...
Tipo: Journal paper
Palavras-chave: Air and water emissions.
Ano: 2004
URL: http://orgprints.org/4062/1/4062.pdf

Effects of green manure storage and incorporation methods on nitrogen release and N2O emissions after soil application
Provedor de dados: 21
Autores: 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

Klimaeffekten af mobil grøngødning
Provedor de dados: 21
Autores: Petersen, Søren O.; Sørensen, Peter.
Klimabelastning bør indgå i vurderingen af dyrkningssystemers bæredygtighed. Vi undersøgte udledningen af drivhusgasser under opbevaring og efter udbringning af gødningsprodukter til økologiske sædskifter: Afhøstet kløvergræs som blev ensileret eller komposteret, og plantebiomasse som blev afgasset sammen med gylle. Både afgasset gylle og ensilage af kløvergræs viste positive resultater mht. merudbytte og klimaeffekt.
Tipo: Newspaper or magazine article
Palavras-chave: Dairy cattle; Farming Systems; Composting and manuring; Farm nutrient management.
Ano: 2014
URL: http://orgprints.org/25342/6/25342.pdf

Effects of green manure storage and incorporation methods on greenhouse gas fluxes and N mineralization after soil application
Provedor de dados: 21
Autores: 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

Nitrous oxide emissions and grassland management
Provedor de dados: 21
Autores: Petersen, Søren O.
Nitrous oxide emissions and grassland management  Søren O. Petersen, Danish Institute of Agricultural Sciences, Dept. Crop Physiology and Soil Science, Denmark    Carbon storage in grasslands is a potentially important mitigation option in support of the Kyoto process. However, the effect of C sequestration by pastures depends significantly on the fate of N inputs via animal deposits, atmospheric N2 fixation or inorganic fertilizers, since N2O derived from N turnover can partly or completely off-set the removal of atmospheric CO2.    Urine spots have been identified as strong sources of N2O, but the quantification of N2O emissions from grazed pastures is complicated by temporal and spatial variability, and by limited understanding of the interactions...
Tipo: Other
Palavras-chave: Air and water emissions.
Ano: 2001
URL: http://orgprints.org/121/1/Dublin_poster_30%2D3%2D2001.ppt

Kvælstofdynamik i økologiske sædskifter
Provedor de dados: 21
Autores: Petersen, Søren O.
Jordens indhold af "aktivt" kvælstof påvirkes af sædskiftet. Kendskab til mængder og dynamik kan fremme selvforsyningen på økologiske bedrifter.
Tipo: Newspaper or magazine article
Palavras-chave: Farming Systems; Soil.
Ano: 2009
URL: http://orgprints.org/16098/1/16098.pdf

Effects of green manure storage and incorporation methods on nitrogen release and N2O emissions after soil application
Provedor de dados: 21
Autores: 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

Sources of nitrogen for winter wheat in organic cropping systems
Provedor de dados: 21
Autores: Petersen, Søren O.; Schjønning, P.; Olesen, Jørgen E.; Christensen, S.; Christensen, B.T.
In organic cropping systems, legumes, cover crops, residue incorporation, and manure application are used to maintain soil fertility, but the contributions of these management practices to soil nitrogen (N) supply remain obscure. We examined potential sources of N for winter wheat (Triticum aestivum L.) in four experimental cropping systems established in 1997 on three soil types. Three of the four systems were under organic management. Topsoil N, depth of the A horizon, and cumulated inputs of N since 1997 were determined at plot level. Labile soil N pools (mineral N, potentially mineralizable N [PMN], microbial biomass N [MBN]) were monitored during two growth periods; at one site, biomass C/N ratios were also determined. Soil for labile N analysis was...
Tipo: Journal paper
Palavras-chave: Crop combinations and interactions; Soil biology; Nutrient turnover; Farm nutrient management.
Ano: 2013
URL: http://orgprints.org/22015/7/22015.pdf

Afgrøderester og sædskifte har stor betydning for udledning af lattergas
Provedor de dados: 21
Autores: Petersen, Søren O.; Schjønning, P.; Ambus, Per.
Lattergas udgør en del af det atmosfæriske tab af kvælstof fra dyrkningsjorden. Målt i kg kvælstof er mængderne små, men fordi lattergas er en meget kraftig drivhusgas, er gassens betydning for landbrugets samlede udledninger stor.
Tipo: Newspaper or magazine article
Palavras-chave: Cereals; Pulses and oilseeds Air and water emissions Farm nutrient management.
Ano: 2011
URL: http://orgprints.org/22013/1/22013.pdf

Nitrous oxide emissions from grazed grassland: effects of cattle management and soil conditions
Provedor de dados: 21
Autores: Petersen, Søren O.; Simek, Miloslav; Stamatiadis, Stamatis; Yamulki, Sirwan.
Traditionally, dairy cattle spend a substantial part of the year on pastures. For organic farming within EU it is specified that ”all mammals must have access to pasturage or an open-air exercise area” which they must be able to use whenever ”weather conditions and the state of the ground permits” (Council Regulation [EEC] No 2092/91 ).  Dairy production systems are characterized by a considerable N surplus, and N deposited during grazing represents a significant risk for environmental losses, including N2O emissions. Excess N is excreted mainly in the urine, the composition of which is influenced by factors such as lactation stage, sward quality and intake of supplements. Resulting N concentrations in urine patches can range from 20 to 80 g N m-2, and...
Tipo: Conference paper, poster, etc.
Palavras-chave: Dairy cattle.
Ano: 2004
URL: http://orgprints.org/4079/1/4079.pdf

Nitrogen mineralization and greenhouse gas emissions after soil incorporation of ensiled and composted grass-clover as green manure
Provedor de dados: 21
Autores: 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

Catch Crop Residues Stimulate N2O Emissions During Spring, Without Affecting the Genetic Potential for Nitrite and N2O Reduction
Provedor de dados: 21
Autores: Duan, Yun-Feng; Hallin, Sara; Jones, Christopher M.; Priemé, Anders; Labouriau, Rodrigo; Petersen, Søren O.
Organic agriculture depends on recycling of N to sustain crop production, and the use of catch crops to prevent leaching losses during winter is part of this strategy. The finding in this study, that catch crop residues were a more consistent source of nitrous oxide emissions in spring than synthetic fertiliser, indicates catch crop residue decomposition may contribute negatively to the climate impact of the farming system. Management practices are needed that reduce the potential for denitrification, which is the main source of nitrous oxide. Possible strategies include cultivation to promote aerobic rather than anaerobic degradation, and timing of manure application to avoid that mineral N from manure accumulates during residue decomposition....
Tipo: Journal paper
Palavras-chave: Crop combinations and interactions; Soil biology; Nutrient turnover; Air and water emissions.
Ano: 2018
URL: http://orgprints.org/36654/1/fmicb_09_02629.pdf

Effects of green manure storage and incorporation methods on nitrogen release and N2O emissions after soil application
Provedor de dados: 21
Autores: 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/27643/25/Carter%20et%20al.%202014_BFOS.pdf

Quantifying biological nitrogen fixation of different catch crops, and residual effects of roots and tops on nitrogen uptake in barley using in-situ 15N labelling
Provedor de dados: 21
Autores: Li, Xiaoxi; Sørensen, Peter; Li, Fucui; Petersen, Søren O.; Olesen, Jørgen E.
Background and aims  Contributions of legume-based catch crops (LBCCs) to succeeding cereals may be significant. We quantified biological N fixation (BNF) and residual N effects of contrasting CC tops and roots.    Methods  BNF of three LBCCs (red clover, winter vetch, perennial ryegrass-red clover mixture) was quantified in microplots by 15N labelling. Their residual effects on spring barley were tested against two non-LBCCs (perennial ryegrass, fodder radish) after spring incorporation of CC tops or roots in monoliths.    Results  Total N accumulated in LBCCs was 153–226 kg N ha−1, of which 62–66 % was derived from BNF in tops and 31–46 % in macro-roots (0–18 cm soil). Macro-roots represented 31–50 % of total plant N. LBCCs showed similar capacity for...
Tipo: Journal paper
Palavras-chave: Pasture and forage crops Cereals; Pulses and oilseeds Nutrient turnover Farm nutrient management.
Ano: 2015
URL: http://orgprints.org/30110/1/LXX2-2015%20PLSO%20vol%20395%20p273%E2%80%93287.pdf

Nitrous oxide emissions from arable soil: Effects of crop rotation, tillage and manure management
Provedor de dados: 21
Autores: Petersen, Søren O.
Soil carbon storage and nitrous oxide (N2O) emissions are both important for the greenhouse gas balance of agricultural soil, but difficult to verify under field conditions due to high spatial and temporal variability. Carbon stock changes are particularly elusive because they occur over decades, and future climate or management changes may revert current trends. Emissions of N2O from arable soil are derived mainly from the short-term (&lt;1 yr) turnover of crop residues, fertilizers and manure, which indicates that mitigation options may be found with a better understanding of management effects on soil C and N cycling and N2O emissions. This presentation will describe N2O studies within long-term crop rotation experiments that allow side-by-side...
Tipo: Conference paper, poster, etc.
Palavras-chave: Nutrient turnover; Soil tillage; Air and water emissions; Farm nutrient management.
Ano: 2011
URL: http://orgprints.org/22016/1/22016.PDF

Evidence for denitrification as main source of N2O emission from residue-amended soil
Provedor de dados: 21
Autores: Li, Xiaoxi; Sørensen, Peter; Olesen, Jørgen E.; Petersen, Søren O.
Catch crops, especially leguminous catch crops, may increase crop nitrogen (N) supply and decrease environmental impacts in cropping systems, but they may also stimulate nitrous oxide (N2O) emissions following spring incorporation. In this 28-day laboratory incubation study, we examined the carbon (C) and N dynamics and N2O evolution after simulated incorporation of residues from three catch crop species into a loamy sand soil, with variable soil moisture (40, 50 or 60% water-filled pore space (WFPS)). The catch crops include two leguminous (red clover and winter vetch) and one non-leguminous species (ryegrass). Plant material was placed in a discrete layer surrounded by soil in which the nitrate (NO3-) pool was enriched with 15N to distinguish N2O derived...
Tipo: Journal paper
Palavras-chave: Pasture and forage crops; Crop combinations and interactions; Nutrient turnover; Air and water emissions; Farm nutrient management.
Ano: 2015
URL: http://orgprints.org/30111/1/LXX3-2016%20SBB%20vol%2092%20p153-160.pdf

Short-term C and N dynamics in urine patches: Response of nitrifiers to different urinary urea levels
Provedor de dados: 21
Autores: Petersen, Søren O.; Bol, Roland; Dittert, Klaus; Christofides, Calliopi; Roslev, Peter; Hansen, Martin N.
Managed grasslands can accumulate soil organic carbon and thereby remove CO2 from the atmosphere. When grazed, however, the interaction between N inputs (fertilization, feeding, N fixation) and excretal returns can lead to sward deterioration and elevated emissions of N2O in urine patches. Both effects may reduce the positive effect of carbon storage on the greenhouse gas balance.    A field plot study was carried out between 19 September and 4 October 2001, in which cattle urine amended with 13C- and 15N-labelled urea was added to a sandy loam pasture. Two levels of urea, corresponding to 23.3 and 39.8 g urea-N m-2, were compared with an unamended control. Ammonia losses corresponded to 14 and 12% of the urea-N applied in the low (UL) and high (UH) urea...
Tipo: Conference paper, poster, etc.
Palavras-chave: Air and water emissions.
Ano: 2004
URL: http://orgprints.org/2906/1/Ghent_presentation_020604.ppt

Effects of green manure storage and incorporation methods on nitrogen release and N2O emissions after soil application
Provedor de dados: 21
Autores: 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/26717/13/Carter%20et%20al.%202014_BFOS_online.pdf

Short term N2O, CO2, NH3 fluxes and N/C transfers in a Danish grass-clover pasture after simulated urine deposition in autumn
Provedor de dados: 21
Autores: Bol, Roland; Petersen, Søren O.; Christofides, Calliopi; Dittert, Klaus; Hansen, Martin Nørregaard.
Urine patches are significant hot-spots of C and N transformations. To investigate the effects of urine composition on C and N turnover and gaseous emissions from a Danish pasture soil, a field plot study was carried out in September 2001. Cattle urine was amended with two levels of 13C- and 15N-labeled urea, corresponding to 5.58 and 9.54 g urea-N l-1, to reflect two levels of protein intake. Urine was then added to a sandy-loam pasture soil equivalent to a rate of 23.3 or 39.8 g urea-N m-2. Pools and isotopic labeling of nitrous oxide (N2O) and CO2 emissions, extractable urea, ammonium (NH4+), and nitrate (NO3-), and plant uptake were monitored during a 14 d period, while ammonia (NH3) losses were estimated in separate plots amended with unlabeled urine....
Tipo: Journal paper
Palavras-chave: Air and water emissions.
Ano: 2004
URL: http://orgprints.org/4060/1/4060.pdf

Long-term effects of cropping system on N2O emission potential
Provedor de dados: 21
Autores: Petersen, Søren O.; Ambus, Per; Elsgaard, Lars; Schjønning, P.; Olesen, Jørgen E.
The potential for N2O emissions outside the main growing season may be influenced by long-term effects of cropping system. This was investigated by collecting intact soil cores (100 cm3, 0-4 cm depth) under winter wheat in three organic cropping systems and a conventional reference within a long-term crop rotation experiment. Average annual inputs of C in crop residues and manure ranged from 1.7 to 3.3 Mg ha-1. A simulated freeze-thaw cycle resulted in a flush of CO2 during the first 48 h, which could be mainly from microbial sources. Other samples were adjusted to approximately –10, -30 or –100 hPa and amended with excess 15NO3- prior to freezing and thawing. Denitrification was the main source of N2O during a 72-h incubation at 22C, as judged from N2O...
Tipo: Journal paper
Palavras-chave: Soil biology; Air and water emissions; Farm nutrient management.
Ano: 2013
URL: http://orgprints.org/22014/1/22014.pdf

Urea concentration affects short-term N turnover and N2O production in grassland soil
Provedor de dados: 21
Autores: Petersen, Søren O.; Stamatiadis, Stamatis; Christofides, C.; Yamulki, Sirwan; Bol, . Roland.
Introduction  For Western Europe it is estimated that, on average, 8% of total N excreted by dairy cattle is deposited during grazing (IPCC, 1997). The intake and excretion of N is influenced by factors such as feed composition, lactation stage and pasture quality, and the excretion of excess N as urea in the urine can therefore vary considerably. Urea can lead to high ammonium levels in the soil which may influence N dynamics and gaseous emissions. This laboratory study was conducted to investigate short-term effects of urea concentration on N2O emissions.     Methods  Solutions containing 0 (CTL), 5 (LU) and 10 g l-1 urea-N (HU) were added to sieved and repacked soil cores of pasture soil at a rate of 4 l m-2. Also, 5 g l-1 urea-N was added to soil...
Tipo: Conference paper, poster, etc.
Palavras-chave: Dairy cattle.
Ano: 2003
URL: http://orgprints.org/1296/1/12th_N_workshop_180903.ppt

Kløvergræs ensilage og kompost som grøngødning
Provedor de dados: 21
Autores: Carter, Mette S.; Ambus, Per; Petersen, Søren O.; Sørensen, Peter.
En ny strategi kan måske forbedre udnyttelsen af det kvælstof, som fikseres af kløverplanter i økologisk planteavl. Vores studie viste en større frigivelse af kvælstof fra ensileret kløvergræs end fra kompost af kløvergræs iblandet halm. Samtidig fandt vi, at indarbejdning af grøngødning ved harvning frem for pløjning reducerede udledningen af den stærke drivhusgas, lattergas.
Tipo: Newspaper or magazine article
Palavras-chave: Nutrient turnover; Air and water emissions.
Ano: 2013
URL: http://orgprints.org/24959/14/24959.pdf

Flow of nutrients and climate relevant gases in experimental rotations on three soil types
Provedor de dados: 21
Autores: Petersen, Søren O.
Within organic farming there is a continued effort to close nutrient cycles in order to improve nutrient use efficiency for crop production while also minimizing environmental impacts. In Denmark a long-term crop rotation experiment on three soil types, i.e., Jyndevad (4.5% clay, 2.0% C), Foulum (8.8% clay, 3.8% C) and Flakkebjerg (15.5% clay, 1.7% C), provides a platform for studies of agronomic and environmental aspects of organic farming. Selected results from investigations at these sites are presented.     In 2007 and 2008 one study determined soil microbial biomass N and mineralizable N on all three locations during the growing season in four selected rotations, three organic and one conventional; the objective was to evaluate the role of soil...
Tipo: Conference paper, poster, etc.
Palavras-chave: Farming Systems; Air and water emissions; Denmark.
Ano: 2009
URL: http://orgprints.org/19468/4/19468.pdf

Effects of contrasting catch crops on nitrogen availability and nitrous oxide emissions in an organic cropping system
Provedor de dados: 21
Autores: Li, Xiaoxi; Petersen, Søren O.; Sørensen, Peter; Olesen, Jørgen E.
Abstract Legume-based catch crops (LBCCs) may act as an important source of nitrogen (N) in organic crop rotations because of biological N fixation. However, the potential risk of high nitrous oxide (N2O) emissions needs to be taken into account when including LBCCs in crop rotations. Here, we report the results from a one-year field experiment, which investigated N availability and N2O emissions as affected by three LBCCs, i.e., red clover (CL), red clover–ryegrass mixture (GC) and winter vetch (WV), two non-LBCCs, i.e., perennial ryegrass (GR) and fodder radish (FR), and a control (CO) without catch crops. The effect of two catch crop management strategies was also tested: autumn harvest of the catch crop versus incorporation of whole-crop residues by...
Tipo: Journal paper
Palavras-chave: Cereals; Pulses and oilseeds Nutrient turnover Air and water emissions Farm nutrient management.
Ano: 2015
URL: http://orgprints.org/28131/2/28131.pdf

Developments in greenhouse gas emissions and net energy use in Danish agriculture - How to achieve substantial CO2 reductions?
Provedor de dados: 21
Autores: Dalgaard, Tommy; Olesen, Jørgen E.; Petersen, B.M.; Petersen, Søren O.; Jørgensen, Uffe; Kristensen, Troels; Hutchings, Nicholas J.; Gyldenkerne, Steen; Hermansen, J.E.
Greenhouse gas (GHG) emissions from agriculture are a significant contributor to total Danish emissions. Consequently, much effort is currently given to the exploration of potential strategies to reduce agricultural   emissions. This paper presents results from a study estimating agricultural GHG emissions in the form of methane, nitrous oxide and carbon dioxide (including carbon sources and sinks, and the impact of energy consumption/bioenergy production) from Danish agriculture in the years 1990-2010. An analysis of possible measures to reduce the GHG emissions indicated that a 50-70% reduction of agricultural emissions by 2050 relative to 1990 is achievable, including mitigation measures in relation to the handling of manure and fertilisers,...
Tipo: Journal paper
Palavras-chave: Nutrient turnover; Air and water emissions; Buildings and machinery; Landscape and recreation; Farm nutrient management.
Ano: 2011
URL: http://orgprints.org/19044/4/19044.pdf

Dynamics of a pasture soil microbial community after deposition of cattle urine amended with [13C]urea
Provedor de dados: 21
Autores: Petersen, Søren O.; Roslev, Peter; Bol, Roland.
Within grazed pastures, urine patches are hot-spots of nitrogen turnover since dietary N surpluses are excreted mainly as urea in the urine. This short-term experiment investigated 13C uptake in microbial lipids after simulated deposition of cattle urine at 10.0 and 17.1 g urea-C m-2. Confined field plots without or with cattle urine amendment were sampled after 4 and 14 days, and soil from 0-5 and 10-20 cm depth was analyzed for content and composition of phospholipid fatty acids (PLFAs), and for the distribution of urea-derived 13C among individual PLFAs. Carbon dioxide emissions were quantified and the contributions derived from urea assessed. Initial changes in PLFA composition were greater at the lower level of urea, as revealed by a principal...
Tipo: Journal paper
Palavras-chave: Soil biology.
Ano: 2004
URL: http://orgprints.org/4061/1/4061.pdf