Sustainable nutrient use on dairy farms in northwest Europe
The View from Teagasc: Dairyman, a project part-funded by Interreg, is aimed at improving resource use efficiency on dairy farms in northwest Europe. The objective was to compare the performances of 127 pilot dairy farms in 10 regions: Ireland, Northern Ireland, Brittany, Pays de la Loire, Nord Pas de Calais, Flanders, Wallonia, Baden Württemberg, Luxembourg and The Netherlands.
The project involved 14 partner organisations and nine knowledge transfer centres. It ran from 2009 to 2013 and on-farm data collection took place on 21 Irish dairy farms over a three-year period from 2009 to 2011.
The use of nutrients on the pilot farms was analysed and compared across the regions. Inputs of fertiliser N, which averaged approximately 200kg/ha in Ireland and Northern Ireland, were consistently greater than the other regions in the study, which averaged approximately 90kg/ha.
However, although fertiliser N input was relatively high on Irish farms, relatively low imports of concentrate and other feeds resulted in surplus N on Irish farms (170kg/ha) being close to the average of the regions in the study.
The average P surplus on farms in regions other than Ireland typically ranged between four and 17kg/ha. However, there was a deficit of
P on the Irish farms; more P was being exported from Irish farms than imported onto Irish farms. The deficit of P on Irish farms can
be attributed to the relatively low levels of concentrates fed per cow and low P fertilisation of grassland. Low P fertilisation of
grassland is attributable to the very restrictive regulations governing P fertilisation of grassland in Ireland and the sharp increase in
the cost of artificial fertiliser P in recent years.
For more information go to www.interregdairyman.eu.
By Andy Boland and James Humphreys, Teagasc
Image: Fertiliser spreading/Photo O’Gorman Photography