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270 Chapter Seven

BO X
Continued
7. 5

Fig. 2 The reduced nitrate concentrations
achieved in (a) soil water beneath an area
converted from arable to permanent grass
and (b) in depth samples of groundwater in
an area of new forest in the Drastrup area,
Denmark. After the Municipality of
Aalborg (2001).

Table 7.3 Summary of measured soil nitrate losses prior to (1990/91) and during the Pilot Nitrate Sensitive Area (NSA) scheme. Fluxes
have been adjusted to mean rainfall conditions. After ADAS (2003).
Crop type N loss winter 1990/91 Mean N loss in winters of 1992/3, 1993/4,
1994/5
−1
−1
−1
−1
kg N ha (adjusted) mg L as NO − n kg N ha (adjusted) mg L as NO − n
3 3
Potatoes, sugar beet 92 ± 23 228 ± 52 10 38 ± 4 87 ± 9 46
Cereals 40 ± 4 102 ± 11 61 53 ± 3 85 ± 5 142
Grass 44 ± 7 102 ± 16 27 42 ± 8 69 ± 14 79
Premium scheme – – 0 6 ± 4 9 ± 6 70
All sites 65 ± 12 163 ± 29 108 47 ± 3 79 ± 5 380