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| Registros recuperados: 11 | |
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| Garland, Gina; Bünemann, E. K.; Oberson, A.; Frossard, E.; Snapp, S.; Chikowo, R.; Six, J.. |
| Effective use of soil phosphorus (P) for crop production requires an understanding of how P pools are stabilized and cycled within soil aggregates, rather than assuming that P dynamics, particularly organic P, closely follow those of C. The main goal of this study was to compare C and N cycling with P dynamics in soil aggregate fractions under two distinct crop species, maize (Zea mays) and pigeon pea (Cajanus cajan) in a highly-weathered Lixisol. We found that while C and N follow an open cycle, whereby C and N are mineralized from microaggregates during macroaggregate turnover and partially exit the soil system as gas and leachate, P has a relatively closed cycle, where most of the mineralized and solubilized P from microaggregates is lost from the... |
| Tipo: Journal paper |
Palavras-chave: Soil. |
| Ano: 2018 |
URL: http://orgprints.org/34709/1/garland-etal-2018-SoilBiolBiochem-Vol116-p91-98.pdf |
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| Bosshard, C.; Frossard, E.; Dubois, D.; Mäder, P.; Manolov, I.; Oberson, A.. |
| Physically separated soil organic matter (SOM) fractions may take different functions in soil N dynamics. We studied the effect of long-term organic matter (OM) management and different soil biological activity on the incorporation of N added with organic and mineral amendments into aggregate fractions and size density fractions. We applied 15N-labeled sheep feces, urine, and mineral fertilizer to microplots installed in plots of conventional (CONMIN) and bio-organic (BIOORG) cropping systems. Soil sampled 112 d after amendment was separated into macro-, microaggregates, and microstructures. Aggregates were then fractionated into free light fraction (LF), intra-aggregate particulate organic matter (iPOM),and the mineral-associated organic matter fraction... |
| Tipo: Journal paper |
Palavras-chave: Soil. |
| Ano: 2008 |
URL: http://orgprints.org/26387/1/Bosshard_et_al_2008_SSSAJ_72_POM.pdf |
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| Oehl, F.; Frossard, E.; Fliessbach, A.; Dubois, D.; Oberson, A.. |
| Soil organic P (Po) mineralization plays an important role in soil P cycling. Quantitative information on the release of available inorganic P (Pi) by this process is difficult to obtain because any mineralized Pi gets rapidly sorbed. We applied a new approach to quantify basal soil Po mineralization, based on 33PO4 isotopic dilution during 10 days of incubation, in soils differing in microbiological activity. The soils originated from a 20 years old field experiment, including a conventional system receiving exclusively mineral fertilizers (MIN), a bioorganic (ORG) and bio-dynamic (DYN) system. Indicators of soil microbiological activity, such as size and activity of the soil microbial biomass and phosphatase activity, were highest in DYN and lowest in... |
| Tipo: Journal paper |
Palavras-chave: Nutrient turnover; Soil biology; Soil quality. |
| Ano: 2004 |
URL: http://orgprints.org/2791/1/Oehl_et_al_2004_SBB_36.pdf |
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| Meyer, G.; Maurhofer, M.; Frossard, E.; Gamper, H. A.; Mäder, P.; Mészáros, É.; Schönholzer-Mauclaire, L.; Symanczik, S.; Oberson, A.. |
| Soil microorganisms exuding organic acids have the potential to solubilize inorganic phosphorus (P), which could improve the P availability to plants growing on calcareous soil. The gluconic acid exuding bacteria Pseudomonas protegens CHA0 can solubilize P under glucose rich in vitro conditions, but evidence on the effectiveness in soil is lacking. This discrepancy in P solubilization between in vitro and in vivo is common for many P solubilizing bacteria. Possible causes for this discrepancy are rarely explored in soil using mechanism oriented approaches. Proposed reasons for limitation of bacterial P solubilization in soil are low persistence of the inoculant or low glucose availability in the plant rhizosphere. To test these two hypotheses we... |
| Tipo: Journal paper |
Palavras-chave: Cereals; Pulses and oilseeds Nutrient turnover. |
| Ano: 2019 |
URL: http://orgprints.org/36362/1/Meyer-etal-2019-SoilBiolBiocehmistry-Vol131-p217-228.pdf |
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| Loes, A-K.; Bünemann, E.; Cooper, J.; Hörtenhuber, S.; Magid, J.; Oberson, A.; Möller, K.. |
| Organic farming systems need to replace nutrients exported via farm products, especially phosphorus (P) which may otherwise become depleted in soil in the long term. In Europe, EU regulations for organic production are shaping the farming systems with respect to inputs of nutrients. Permitted off-farm P sources include conventional animal manure, composted or anaerobically digested organic residues, rock phosphate, and some animal residues such as meat and bone meal. The recent proposed revision of EU regulations for organic production (2014) puts less emphasis on closing nutrient cycles and instead aims at minimizing off-farm inputs, to reduce the risk of importing contaminants. This development, which has received little attention from the organic sector... |
| Tipo: Journal paper |
Palavras-chave: Soil quality; Composting and manuring; Regulation. |
| Ano: 2016 |
URL: http://orgprints.org/32308/1/loes-etal2016-OrgAgri-online-p1-24.pdf |
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| Bosshard, C.; Sørensen, P.; Frossard, E.; Mayer, J.; Mäder, P.; Nanzer, S.; Oberson, A.. |
| Nitrogen (N) utilisation by crops has to be improved to minimize losses to the environment. We investigated N use efficiency of animal manure and mineral fertiliser and fate of fertiliser N not taken up by crops in a conventional (CONMIN) and a bioorganic (BIOORG) cropping system of a long-term field experiment over three vegetation periods (winter wheat–soybean–maize). Microplots planted with wheat received a single application of 15N-labelled slurries (either urine or faeces labelled) or mineral fertiliser. At the end of each vegetation period we tested whether higher microbial activity and larger microbial biomass in BIOORG than CONMIN soils, and lower long-term N input level in BIOORG, affected use efficiency and fate of fertiliser N not taken up by... |
| Tipo: Journal paper |
Palavras-chave: Soil. |
| Ano: 2009 |
URL: http://orgprints.org/26369/1/Bosshard_etal_2009_NCA83.pdf |
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| Oehl, F.; Oberson, A.; Tagmann, H.U.; Besson, J.M.; Dubois, D.; Mäder, P.; Roth, H.-R.; Frossard, E.. |
| The aim of this work was to assess to which extent organic farming practices would affect the accumulation of total and available phosphorus (P) in a cropped soil in comparison to conventional practices. In order to achieve this, soil samples were taken from a long-term field trial comparing a non-fertilised control (NON), two conventionally cultivated treatments (MIN, CON), and two organically cultivated treatments (ORG, DYN). Soil samples were taken from each treatment at two depths (0-20 and 30-50 cm) before starting the field trial (1977) and at the end of every three crop rotations (1984, 1991 and 1998). They were then analysed for total P (Pt ), total inorganic P (Pi ), total organic P (Po) and isotopically exchangeable Pi . After 21 years, the... |
| Tipo: Journal paper |
Palavras-chave: Soil. |
| Ano: 2002 |
URL: http://orgprints.org/26761/1/Oehl_et_al_2002_NCA.pdf |
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| Garland, Gina; Bünemann, E. K.; Oberson, A.; Frossard, E.; Six, J.. |
| Background and aims In Malawi, strategies are being sought to boost maize production through improvements in soil fertility. This study assessed the impact of intercropping maize (Zea mays) with pigeon pea (Cajanus cajan) in Lixisols of Malawi on yield, biological N fixation, soil aggregation, and P forms within soil aggregates. Methods Maize and pigeon pea were grown intercropped in pots, with varying degrees of root interaction in order to understand the relative importance of biochemical versus physical rhizospheric interactions. Following harvest, soils were separated into aggregate fractions using wet-sieving, and the nutrient content of all fractions was assessed. Results The proportion of macroaggregates and microaggregates increased by 52 and... |
| Tipo: Journal paper |
Palavras-chave: Soil quality; Root crops. |
| Ano: 2017 |
URL: http://orgprints.org/32324/1/garland-etal-2017-PlantSoil-Vol-415-Issue1-2-p37-55.pdf |
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| Oberson, A.; Frossard, E.; Bühlmann, C.; Mayer, J.; Mäder, P.; Lüscher, A.. |
| Background and aim Symbiotic dinitrogen (N2) fixation is the most important external N source in organic systems. Our objective was to compare symbiotic N2 fixation of clover grown in organically and conventionally cropped grass-clover leys, while taking into account nutrient supply gradients. Methods We studied leys of a 30-year-old field experiment over 2 years in order to compare organic and conventional systems at two fertilization levels. Using 15N natural abundance methods, we determined the proportion of N derived from the atmosphere (PNdfa), the amount of Ndfa (ANdfa), and the transfer of clover N to grasses for both red clover (Trifolium pratense L.) and white clover (Trifolium repens L.). Results In all treatments and both years, PNdfa was... |
| Tipo: Journal paper |
Palavras-chave: Nutrient turnover; Crop husbandry. |
| Ano: 2013 |
URL: http://orgprints.org/23228/1/Oberson-etal-2013-PlantansSoil-onlinefirst.pdf |
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| Oberson, A.; Nanzer, S.; Bosshard, C.; Dubois, D.; Mäder, P.; Frossard, E.. |
| Nitrogen (N) is often the most limiting nutrient in organic cropping systems. N2 fixing crops present an important option to improve N supply and to maintain soil fertility. In a field experiment, we investigated whether the lower N fertilization level and higher soil microbial activity in organic than conventional systems affected symbiotic N2 fixation by soybean (Glycine max, var. Maple Arrow) growing in 2004 in plots that were since 1978 under the following systems: bio-dynamic (DYN); bio-organic (ORG); conventional with organic and mineral fertilizers (CON); CON with exclusively mineral fertilizers (MIN); non-fertilized control (NON). We estimated the percentage of legume N derived from the atmosphere (%Ndfa) by the natural abundance (NA) method. For... |
| Tipo: Journal paper |
Palavras-chave: Nutrient turnover Cereals; Pulses and oilseeds. |
| Ano: 2007 |
URL: http://orgprints.org/13460/1/oberson-etal-2007-plant-and-soil_290_69-83.pdf |
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| Registros recuperados: 11 | |
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