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| Registros recuperados: 10 | |
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| Halberg, Niels; Kristensen, Ib Sillebak; Møller, Berit E.. |
| At begrænse tabet af nærringsstoffer til det omgivende miljø indgår som en del af mange landmænds mål for god driftledelse. Det er vanskeligt at måle eller beregne det faktiske tab af kvælstof fra husdyrbedrifter, og der findes endnu ingen modeller, som kan beregne de enkelte tabsposter rimeligt præcist og samtidigt redegør for den samlede omsætning af kvælstof (N) på bedriften. Separate opgørelser af udnyttelse og tab af N fra enten besætning eller marker giver et mangelfuldt billede af bedriftens reelle udnyttelse af N. Derimod kan en beregning af en husdyrbedrifts samlede omsætning og overskud af N give et godt udtryk for det potentielle N-tab til det omgivende miljø. Ved DJF er der i flere år udført analyser af N-omsætningen og N-udnyttelse i... |
| Tipo: Newspaper or magazine article |
Palavras-chave: Farm nutrient management; Air and water emissions. |
| Ano: 1998 |
URL: http://orgprints.org/13116/1/13116.pdf |
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| Halberg, Niels; Hermansen, John E.; Kristensen, Ib Sillebak; Eriksen, Jørgen; Tvedegaard, Niels; Petersen, Bjørn Molt. |
| Organic rules for grazing and access to outdoor area in pig production may be met in different ways, which express compromises between considerations for animal welfare, feed self-reliance and negative environmental impact such as greeehouse gas emissions and nitrate pollution. This article compares environmental impact of the main organic pig systems in Denmark. Normally sows are kept in huts on grassland and finishing pigs are being raised in stables with access to an outdoor run. One alternative practised is rearing also the fattening pigs on grassland all year round. The third method investigated was a one-unit pen system mainly consisting of a deep litter area under a climate tent and with restricted access to a grazing area. Using life cycle... |
| Tipo: Journal paper |
Palavras-chave: Pigs. |
| Ano: 2010 |
URL: http://orgprints.org/16754/1/16754.pdf |
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| Halberg, Niels; Hermansen, John E.; Kristensen, Ib Sillebak; Eriksen, Jørgen; Tvedegaard, Niels. |
| Organic pig production has emerged as an alternative to the intensive conventional pig production in Europe with the animals confined indoors and often an imbalance between livestock and land for feed production and manure utilisation. The organic systems aim at improving animal welfare by supporting the pig’s natural behaviour (Hermansen et al., 2003), and improving soil fertility by better linking crop and livestock production from an agro-ecological point of view. The differences between organic and conventional pig production is more fundamental than for example differences between dairy production systems, which may be why the share of pig herds within the organic holdings is considerably lower than the percentage of pig herds in conventional... |
| Tipo: Conference paper, poster, etc. |
Palavras-chave: Environmental aspects; Pigs. |
| Ano: 2008 |
URL: http://orgprints.org/15585/1/15585.pdf |
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| Tvedegaard, Niels; Kristensen, Ib Sillebak; Kristensen, Troels. |
| Udviklingen inden for den økologiske kvægproduktion resulterer i større bedrifter. En ofte afledt effekt af udviklingen er, at afgræsning med malkekøer ikke er mulig på en del bedriftens arealer pga. store afstande og eller fysiske forhindringer i form af veje mellem mark og stald-faciliteter, hvorfor det er en særlig udfordring at udnytte græsmarken via afgræsning og at sikre en hensigtsmæssig placering af græsmarkerne i sædskiftet til sikring af bedriftens produktion, økonomi og næringsstofomsætning. Til understøttelse af den strategiske rådgivning og beslutningstagen er der derfor udarbejdet et modelværktøj med fokus på denne problemstilling. I det følgende er beskrevet model forudsætninger og vist enkelte resultater af udvalgte scenarier. Modellen er... |
| Tipo: Report chapter |
Palavras-chave: Farming Systems; Animal husbandry; Feeding and growth; Farm nutrient management. |
| Ano: 2010 |
URL: http://orgprints.org/17919/1/17919.pdf |
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| Kristensen, Troels; Kristensen, Ib Sillebak; Sehested, Jakob. |
| I kapitlet beskrives tre produktionssystemer, som har kørt på Den Økologiske Forsøgsstation Rugballegård gennem tre år: 1) Mælkeproduktion, 2) Svineproduktion samt 3) Kombineret produktion af svin og kvæg, hvor køerne tildeles et reduceret niveau af tilskudsfoder. Kvægbesætningen blev således delt i to hold: N på normalt foderniveau, som afspejlede det rene mælkeproduktionssystem; og L på lavt foderniveau, som afspejlede kombinationssystemet, hvor det energirige foder blev brugt til svineproduktionen. Systemerne er beskrevet gennem modelberegninger og gennem resultater fra Rugballegård. Modelberegningerne viser den højeste gennemsnitlige afgrødeproduktion på 5650 kg ts per ha i kvægsædskiftet (tilhørende malkekvæg på normalt foderniveau) mod 3250 kg ts per... |
| Tipo: Report chapter |
Palavras-chave: Production systems. |
| Ano: 2002 |
URL: http://orgprints.org/202/1/Microsoft_Word_%2D_nr_17_kap_4.pdf |
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| Halberg, Niels; Kristensen, Erik Steen; Kristensen, Ib Sillebak. |
| Separate focus on crop fertilization or feeding practices inadequately describes nitrogen (N) loss from mixed dairy farms because of (1) interaction between animal and crop production and between the production system and the manager, and (2) uncertainties of herd N production and crop N utilization. Therefore a systems approach was used to study N turnover and N efficiency on 16 conventional and 14 organic private Danish farms with mixed animal (dairy) and crop production. There were significant differences in N surplus at the farm level (242 kg. N/ha. vs. 124 kg. N/ha. on conventional and organic dairy farms respectively) with a correlation between stocking rate and N surplus. N efficiency was calculated as the output of N in animal products divided by... |
| Tipo: Journal paper |
Palavras-chave: Farm nutrient management. |
| Ano: 1995 |
URL: http://orgprints.org/13010/1/13010.pdf |
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| Kristenseen, Troels; Søegaard, Karen; Kristensen, Ib Sillebak. |
| By the intensifying of the livestock production with specialised and larger farm units the role of grassland has been reduced. The change in EU policy from a production-oriented marked to a marked where the choice of crop is linked to its added value; grassland has an opportunity to come back. However, the aim for research and farming practice within grassland management should be seen in this new context. The paper reviews different production and management systems, mainly stressed on grazing systems, within intensive dairy farming and aspects of feeding and quality of herbage in order to propose areas of special interest seen in the new context. Farming systems based on homegrown feed, as organic farming and systems based on legumes, need to be further... |
| Tipo: Journal paper |
Palavras-chave: Production systems. |
| Ano: 2005 |
URL: http://orgprints.org/4693/1/4693.pdf |
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| Registros recuperados: 10 | |
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