Farming strategies and nutrient balances in organic farming systems in Denmark
Danish Institute of Plant and Soil Science.Department of Soil Science, Research Centre Foulum, P.O Box 23, DK-8830 Tjele.
|In Denmark, Danish Institute of Plant and Soil
Science takes care of Research in Cropping Systems. Ecological crop rotations have been
established, since 1987, at three state research stations. Results from the first rotation
of a six year fodder crop rotation will be presented. The crop rotation is situated at
Research Centre Foulum in the middle of Jutland. The soil type is a coarse sandy loam.The
crops have been established in fields of about 1 ha and all crops are present each year.
Nutrient balances, yields, pests and diseases, soil nutrients content etc have been
measured.In the fodder crop production system nearly half of the area is covered with
leguminous plant in combination with grass and cereals. Clover grass and thereby the
fixation of nitrogen has been, as years pass, the main fertilizer for the other crops in
the rotation. Potassium, on the other hand, with the high input of nitrogen, become the
limiting regulator of yield in the rotation. Farm management and a well designed crop
rotation conserving nitrogen and controlling weed, are main factors in making ecological
and economic sustainable farming systems. A main problem in the long run will be the
decreasing value of potassium and how to compensated the loss. In the first rotation very
high yields have lowered the plant available potassium. Yield, nutrient balances for N, P
and K and farm management will be presented.
Mikkelsen, G. & Mikkelsen, S.A. 1989. Start of Farming Systems Research in Denmark. WPRS Bull. (Bull. SROP), 1989. XII, 5, 7-15.
Mikkelsen, G. 1990. Research in ecological cropping systems at the Danish Research Service for Plant and Soil Science. Biological Farming in Europe. Reur Technical Series 12, 1990.