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| Chirinda, N.; Carter, M.S; Albert, K.R.; Ambus, P.; Olesen, J.E.; Porter, J.R.; Petersen, S.O.. |
| Conventional cropping systems rely on targeted short-term fertility management, whereas organic systems depend, in part, on long-term increase in soil fertility as determined by crop rotation and management. Such differences influence soil nitrogen (N) cycling and availability through the year. The main objective of this study was to compare nitrous oxide (N2O) emissions from soil under winter wheat (Triticum aestivum L.) within three organic and one conventional cropping system that differed in type of fertilizer, presence of catch crops and proportion of N2-fixing crops. The study was replicated in two identical long-term crop rotation experiments on sandy loam soils under different climatic conditions in Denmark (Flakkebjerg–eastern Denmark and... |
| Tipo: Journal paper |
Palavras-chave: Farming Systems; Air and water emissions; Environmental aspects. |
| Ano: 2010 |
URL: http://orgprints.org/18510/1/chirinda_et_al_2010_%28N2O%29.pdf |
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| Ambus, P.. |
| Kløvergræs er et vigtigt element i økologisk mælkeproduktion. Flere undersøgelser har dog antydet at denne driftsform rummer en risiko for uønskede udslip af gasformige kvælstof-forbindelser til omgivelserne. En af de gasformer der er særlig opmærksomhed omkring, er lattergas, der er en kraftig drivhusgas med en væsentlig betydning for den globale opvarmning. Af det samlede danske udslip af drivhusgasser, udgør lattergas mere end 10%, hovedsalig udledt ved landbrugsaktivitet. Biologisk kvælstof-fiksering er en nøgleproces i kløvergræssystemer, men vores viden om processen er endnu ufuldstændig, specielt når det gælder bidraget fra rodbiomassen. Af samme grund eksisterer der heller ingen viden om, hvor meget af det fikserede kvælstof, som atter frigives til... |
| Tipo: Newspaper or magazine article |
Palavras-chave: Air and water emissions. |
| Ano: 2002 |
URL: http://orgprints.org/4157/1/Ambus_mark.pdf |
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| Ambus, P.. |
| These results show that emission of N2O is greater when N is added as urine compared with mineral N. This can probably be explained by the presence of organic carbon compounds in the urine, which may fuel the N2O production. Moreover, there is a greater exchange of N between the applied urine-N pool and the soil indigenous N-pool compared with the added mineral N-pool and soil indigenous N, which also indicates an increased microbial activity in the urine patches. The urea content of the urine seemed to be of importance for N2O emissions, suggesting dietary regulations of urine N-composition as a N2O mitigation option. |
| Tipo: Conference paper, poster, etc. |
Palavras-chave: Crop husbandry. |
| Ano: 2004 |
URL: http://orgprints.org/2286/1/pambus040204.pdf |
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| Johansen, A.; Hauggaard-Nielsen, H.; Ambus, P.; Dalgaard, T.; Jørgensen, U.; Nielsen, A.M.; Nielsen, L.H.; Olesen, J.E.; Roepstorff, A.; Skytte, K.; Smith, J.E.; Thomsen, A.B.; Carter, M.S.; Jensen, E.S.. |
| Production of bioenergy in organic agriculture may be implemented in the future to reduce the reliance on non-renewable fossil fuels and minimize greenhouse gas (GHG) emissions. Therefore it is important to assess the potential effect this may have on soil quality and biological parameters. This project aims at designing and evaluate a combined concept for biomass and bio-energy production in OA, while considering soil bio-geo-chemical cycling of plant nutrients and biodiversity of the soil microbiota. |
| Tipo: Conference paper, poster, etc. |
Palavras-chave: Nutrient turnover; Soil biology; Biodiversity and ecosystem services; Soil quality; Air and water emissions; Farm economics; Farm nutrient management; Quality and evaluation of inputs. |
| Ano: 2008 |
URL: http://orgprints.org/15157/1/15157.pdf |
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| Ambus, P.. |
| Organic farming practises, and in particular dairy production systems based on grass-clover pastures are becoming increasingly abundant within Danish agriculture. Grass-clover pastures may provide a mitigation option to reduce grassland nitrous oxide (N2O) emissions (Velthof et al. 1998). The objectives of this work was to examine the relationship between N2O emissions and transformations of inorganic N in organically managed grass-clover pastures of different ages. Results from the project will be used for calibration of the FASSET whole-farm nitrogen transformation model. |
| Tipo: Conference paper, poster, etc. |
Palavras-chave: Air and water emissions. |
| Ano: 2002 |
URL: http://orgprints.org/123/1/123.pdf |
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| Ambus, P.; Petersen, S.O.; Soussana, J.-F.. |
| Deposition of urine and dung by grazing animals is a strong source for N2O production and evolution in grass pastures. Investigations have shown that at least 20% of the annual losses of N2O from a grazed pasture may be associated with urine patches. Moreover, it is well known that urine depositions causes plant damage (scorching) and root death. It can therefore be hypothesized that organic C is released, which may further stimulate the production of N2O. In this study we have used combined 13C-pulse labeling and 15N-labeled urine in order to determine the amount of plant derived C respired in response to the urine application and assess the N2O emission factor from urine patches. Over a six weeks course the cumulated amount of CO2 evolved equaled the... |
| Tipo: Journal paper |
Palavras-chave: Pasture and forage crops; Air and water emissions. |
| Ano: 2007 |
URL: http://orgprints.org/10143/1/AGEE2979-Jan2007.pdf |
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| Thyme, M.; Ambus, P.. |
| The contribution of biologically fixed dinitrogen (N2) to the nitrous oxide (N2O) production in grasslands is unknown. To assess the contribution of recently fixed N2 as a source of N2O and the transfer of fixed N from clover to companion grass, mixtures of white clover and perennial ryegrass were incubated for 14 days in a 15N2-enriched atmosphere (0.4 atom% excess). Immediately after labelling, half of the grass-clover pots were sampled for N2 fixation determination, whereas the remaining half were examined for emission of 15N labelled N2O for another eight days using a static chamber method. Biological N2 fixation measured in grass-clover shoots and roots as well as in soil constituted 342, 38 and 67 mg N m-2 d-1 at 16, 26 and 36 weeks after emergence,... |
| Tipo: Journal paper |
Palavras-chave: Nutrient turnover; Pasture and forage crops; Air and water emissions. |
| Ano: 2004 |
URL: http://orgprints.org/4148/1/4148.pdf |
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| Ambus, P.. |
| Gennem de seneste årtier har der været stigende opmærksomhed omkring udledningen af drivhusgasser i forbindelse med landbrugsproduktionen, og megen forskning har været rettet mod at identificere de væsentligste kilder og mulige afværgeforanstaltninger. I forbindelse med planteproduktion er det især anvendelsen af kvælstof(N)-holdige gødningstyper, mineralske såvelsom husdyrbaserede, som bidrager til udslip af den vigtige drivhusgas lattergas. |
| Tipo: Newspaper or magazine article |
Palavras-chave: Air and water emissions. |
| Ano: 2004 |
URL: http://orgprints.org/4158/1/Ambus_%C3%B8koljordb0804.pdf |
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