Table 14.5 - Area coefficients for nitrate losses to surface waters from river catchments with different landuse characteristics

Country/region Characteristics of catchment area Area coefficient, kg N/ha/year Reference
11 EU/EFTA countries (average of 30 catchments) Forest, scrub, heath or grassland 1.6** Hornung et al (1990)
France Forest 2­7 Pierre and Prat (1989)
Nordic countries <10 per cent agriculture 0.6 EEA-TF questionnaire
Finland Forest 1.3­3.1* Rekolainen (1989)
Sweden Forest 1.3 Ryding and Forsberg (1979)
Sweden Mixed agriculture 16 Ryding and Forsberg (1979)
Switzerland Mixed agriculture 16­21 Gächter and Furrer (1972)
Finland Mixed agriculture 7.6­20* Rekolainen (1989)
UK (Devon) Grassland 8­51 Webb and Walling (1985)
Northern Ireland Mainly grassland 3.4­17 Smith (1977)
Poland (Pomerania) 55­75 per cent arable land 1­1.3 Taylor et al (1986)
Denmark Averages for various types of agriculture on different soil types 13­20 Christensen et al (1993)
France Intensive cereal production 15­18 Pierre and Prat (1989)
Central and Eastern Europe (Poland, Czech Republic, Latvia, Lithuania) >50 per cent agriculture 3.0 EEA-TF questionnaire
former USSR (different regions) Various types of arable land 31­104* Kudeyarov and Bashkin (1984)
UK (Shenley Brook) Clay soils, 23 per cent arable land 17­74 Roberts (1987)
Wales Agricultural grazing 5­25 Brooker and Johnson (1984)

Notes:
*Total nitrogen.
**A few of these baseline catchments, however, show relatively large output of nitrate (>10 kg N/ha/year); this is either because of changed N dynamics due to forest damage or site preparation for afforestation including ploughing and drainage.