Balance for nitrogen in agriculture in the Netherlands, 2000
Every year, large quantities of nitrogen enter agriculture, primarily in livestock feed and chemical fertilisers. Withdrawal takes place through animal and vegetable products. There is an annual surplus that places a burden on soil and air.
Return flows within agriculture
Within agriculture, two nitrogen return flows can be distinguished. In the first, nitrogen withdrawn from the soil in crops such as green maize and grass is returned directly to the livestock industry. The second flow is the deposition of volatilised ammonia (NH3) on agricultural land. This NH3 comes from the excretion and storage of manure, the application of manure and fertiliser on agricultural land, and crop storage (mainly green maize and silage).
Return flows outside agriculture
There are two return flows which occur partly outside agriculture. Some agricultural products such as grain are returned directly to the compound feed industry. Others reach the compound feed industry and livestock farming through the food and drinks industry. This is waste generated during the processing of animal and vegetable products. A large proportion of both streams is used as concentrated feed in agriculture. The rest is exported or sold as animal feed outside the agriculture sector.
