| Registro completo |
| Provedor de dados: |
Rev. Bras. Ciênc. Solo
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| País: |
Brazil
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| Título: |
Sheep Excreta as Source of Nitrous Oxide in Ryegrass Pasture in Southern Brazil
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| Autores: |
Tomazi,Michely
Magiero,Emanuelle Cavazini
Assmann,Joice Mari
Bagatini,Tatiane
Dieckow,Jeferson
Carvalho,Paulo Cesar de Faccio
Bayer,Cimélio
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| Data: |
2015-10-01
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| Ano: |
2015
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| Palavras-chave: |
Climate change
Emission factor
Urine
Dung
Crop-livestock system
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| Resumo: |
ABSTRACT Livestock urine and dung are important components of the N cycle in pastures, but little information on its effect on soil nitrous oxide (N2O) emissions is available. We conducted a short-term (39-day) trial to quantify the direct N2O-N emissions from sheep excreta on an experimental area of ryegrass pasture growing on a Typic Paleudult in southern Brazil. Four rates of urine-N (161, 242, 323, and 403 kg ha-1 N) and one of dung-N (13 kg ha-1 N) were applied, as well as a control plot receiving no excreta. The N2O-N emission factor (EF = % of added N released as N2O-N) for urine and dung was calculated, taking into account the N2O fluxes in the field, over a period of 39 days. The EF value of the urine and dung was used to estimate the emissions of N2O-N over a 90-day period of pasture in the winter under two grazing intensities (2.5 or 5.0 times the herbage intake potential of grazing lambs). The soil N2O-N fluxes ranged from 4 to 353 µg m-2h-1. The highest N2O-N fluxes occurred 16 days after application of urine and dung, when the highest soil nitrate content was also recorded and the water-filled pore space exceeded 60 %. The mean EF for urine was 0.25 % of applied N, much higher than that for dung (0.06 %). We found that N2O-N emissions for the 90-day winter pasture period were 0.54 kg ha-1 for low grazing intensity and 0.62 kg ha-1 for moderate grazing intensity. Comparison of the two forms of excreta show that urine was the main contributor to N2O-N emissions (mean of 36 %), whereas dung was responsible for less than 0.1 % of total soil N2O-N emissions.
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| Tipo: |
Info:eu-repo/semantics/article
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| Idioma: |
Inglês
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| Identificador: |
http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832015000501498
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| Editor: |
Sociedade Brasileira de Ciência do Solo
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| Relação: |
10.1590/01000683rbcs20140497
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| Formato: |
text/html
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| Fonte: |
Revista Brasileira de Ciência do Solo v.39 n.5 2015
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| Direitos: |
info:eu-repo/semantics/openAccess
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