Autor: |
Cecilia Lindahl, Eva Salomon, Lena Rodhe, Kristina Lindgren, Johan Malgeryd |
Rok vydání: |
2012 |
Předmět: |
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Zdroj: |
The Open Agriculture Journal. 6:27-35 |
ISSN: |
1874-3315 |
Popis: |
Ammonia (NH 3 ) emissions originate predominantly from manure. In outdoor pig production, excretory behav- iour creates nitrogen (N) point loads. This study examined ammonia losses from pigs on grassland at two farms by calcu- lating N field balances per pen and sub-areas preferred (P) and not preferred (NP) for excretion. Spatial variation in am- monia losses was measured with an equilibrium concentration method in one pen per farm during two years at the end of the fattening period. Cumulative ammonia losses during a fattening period were measured using a micrometeorological mass balance method. P sub-areas had 10- to 100-fold higher amounts of excreted N than NP sub-areas. Ammonia losses were higher from P sub-areas (0.056-1.843 g NH 3 ha -1 hr -1 ) than from NP sub-areas (0.001-0.332 g NH 3 ha -1 hr -1 ). Am- monia losses from NP sub-areas varied more widely. Cumulative NH 3 losses were 28 kg pen -1 . Gross NH 3 losses were 0.66 kg N pig -1 , representing 14% of excreted N. |
Databáze: |
OpenAIRE |
Externí odkaz: |
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