| Registro completo |
| Provedor de dados: |
Organic Eprints
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| País: |
Germany
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| Título: |
Incorporation of Nitrogen-15-Labeled Amendments into Physically Separated Soil Organic Matter Fractions
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| Autores: |
Bosshard, C.
Frossard, E.
Dubois, D.
Mäder, P.
Manolov, I.
Oberson, A.
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| Data: |
2008
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| Ano: |
2008
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| Palavras-chave: |
Soil
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| Resumo: |
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 (MF). Of total soil N, 67% was contained in macroaggregates. Size density fractionation of aggregates revealed that about 60% of soil N was stored in MF while LF and iPOM contained together <3% of soil N. Despite longterm OM input and higher soil biological activity in BIOORG than CONMIN the two soils did not differ in the distribution and content of N in aggregate and size density fractions. Recovery of 15N in nonfractionated soil ranged from 20% (SlurryF) to 25% (SlurryU) of originally applied 15N. The small macroaggregates were for each amendment the major sink (7–12% of applied 15N). In all aggregates and for all amendments, MF was the most important 15N sink, totally containing between 6.6% (SlurryF) to 11.6% (SlurryU) of applied 15N. Less than 1% of applied 15N was recovered in LF, and even less (<0.5%) in iPOM. The proportion of amendment-derived N in aggregate fractions and in several size density fractions (LF, fi ne iPOM, MF) was higher for urine than for feces and mineral fertilizer. Recovery of urine-derived 15N was greater in aggregate fractions of BIOORG than CONMIN soil. During dispersion of aggregates to obtain iPOM and MF, about 27% of total soil N and between 37 and 55% of 15N contained in non-fractionated soil was lost, showing the importance of aggregation to protect N.
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| Tipo: |
Journal paper
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| Identificador: |
http://orgprints.org/26387/1/Bosshard_et_al_2008_SSSAJ_72_POM.pdf
Bosshard, C.; Frossard, E.; Dubois, D.; Mäder, P.; Manolov, I. and Oberson, A. (2008) Incorporation of Nitrogen-15-Labeled Amendments into Physically Separated Soil Organic Matter Fractions. Soil Science Society of America Journal, 72 (4), pp. 949-959.
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| Relação: |
http://orgprints.org/26387/
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| Formato: |
application/pdf
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