Keywords: Pig manure, manure disposal, manure transport, transport costs, transport energy, transport distance, GIS-based networks, INSPIRE Directive, ALLOCATE program.

There has been considerable debate in Ireland about the impacts of the Nitrates Directive (Directive 91/676/EEC) on the pig industry in relation to the 170 kg/ha organic N limit mandated in the Directive and the possible inclusion of an upper limit for phosphorus. Such requirements, especially a phosphorus limit, will lead to more restrictive rules on slurry spreading. The argument centers around whether there is sufficient suitable arable land to meet the needs of the pig industry for spreading pig slurry. At a national level, a key difficulty in Ireland is a lack of accurate data on the real transport distances involved in getting pig slurry from producer locations to potential arable land for spreading.

A full road-based network analysis has been performed in a Geographic Information Systems (GIS) software environment on a pilot area of Ireland examining the location of pig producing facilities and potential arable land. The allocation procedure as run in its current form has proved to be powerful analysis tool in providing a mechanism to generate very close approximations to the real transport distances that pig facilities need to transport pig slurry. Real transport distances then have to be viewed in relation to the range of costs involved in transport.

Our calculations indicate that manure transport from livestock farms to arable farms becomes energetically questionable beyond distances of 50-75 km. From a financial point of view manure could be transported over much longer distances if the arable farmer only had to pay for the costs of transport and spreading. Transporting manure is not a self-evident solution under all circumstances.

Réamonn Fealy, Teagasc, Kinsealy Research Center, Malahide Road, Dublin 17, Ireland.
Jaap Schröder, Plant Research International B.V., Agrosystems Research, Wageningen University, P O Box 16, NL-6700 AA Wageningen, Netherlands.

28 pages, 10 figures, 3 tables, 35 references.