Nitrogen distribution and potential nitrate leaching in a combined ...

Mean N concentration in miscanthus plant material after harvest in August 2009 are registered
in table 3. SD indicates standard deviations. Spring harvested miscanthus was investigated by
Jørgensen (1997) from 1993 to 1995 and the average N concentration of the plant material
from this investigation was included in the table. The highest concentrations of N were
registered in a willow evaporation bed at the locality Gesten (55° 32´N, 9° 11´E). The young
aged ‘Jorr’ and ‘Bjørn’ had crop N off-takes of 170 kgN/ha. The N concentrations of ‘Jorr’ at
research center Foulum were not as high as in Gesten. In Gesten harvest was performed in
September before defoliation. Mineral fertilizer did not have an effect on the N concentration
of plant material at the Foulum locality. An affect of the higher supply of N in the small
paddocks was observed in the N concentration of the miscanthus plant material.
To sum up, high N concentrations of willow plant material were shown in Gesten, while
willow from Foulum had a lower N concentration of the plant material.
3.3.3 Nitrogen balance
Results quantifying inputs to and outputs from each pig system and the willow reference area
are shown in table 4.
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