caa a22 4500 463208889 CHVBK 20180405153134.0 cr unu---uuuuu 170326e20070201xx s 000 0 eng 10.1007/s10705-006-9051-9 doi (NATIONALLICENCE)springer-10.1007/s10705-006-9051-9 Nitrate in upper groundwater on farms under tillage as affected by fertilizer use, soil type and groundwater table [Elektronische Daten] [F. de Ruijter, L. Boumans, A. Smit, M. van den Berg] Indicators are needed to check whether policies on protection of groundwater are effective and if regulations are complied with. We evaluated various indicators at different scales, both in space and in time, and at different degrees of complexity. Groundwater was sampled on 34 arable farms for 3years. Nitrate concentration in upper groundwater was low on clay soil. On sandy soil, peat layers reduced the nitrate concentration with about 80mg/l on average. Sandy soils with high groundwater tables had nitrate concentrations that were less than half of those at sandy soils with low groundwater tables. The relationship between different fertilization variables and nitrate in groundwater was investigated for sandy soils without peat layers. N surplus poorly correlated with nitrate concentrations in groundwater when individual sampling points were studied, but clearly increased when data were averaged at the farm level. Soil mineral nitrogen correlated best with nitrate concentrations in groundwater. The relationships show that especially on well drained soil drastic measures will be inevitable to reach good water quality. Springer Science+Business Media B.V., 2006 Arable farming nationallicence Bulb cultivation nationallicence Element balance nationallicence Horticulture nationallicence Nitrogen nationallicence Nutrient balance nationallicence Nursery stock production nationallicence de Ruijter F. Plant Research International, Wageningen University and Research Centre, P.O. Box 16, 6700 AA, Wageningen, The Netherlands aut Boumans L. National Institute For Public Health and the Environment, Bilthoven, The Netherlands aut Smit A. Plant Research International, Wageningen University and Research Centre, P.O. Box 16, 6700 AA, Wageningen, The Netherlands aut van den Berg M. South African Sugarcane Research Institute (SASRI), Mount Edgecombe, South Africa aut Nutrient Cycling in Agroecosystems Kluwer Academic Publishers 77/2(2007-02-01), 155-167 1385-1314 77:2<155 2007 77 10705 https://doi.org/10.1007/s10705-006-9051-9 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10705-006-9051-9 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- de Ruijter F. Plant Research International, Wageningen University and Research Centre, P.O. Box 16, 6700 AA, Wageningen, The Netherlands aut NATIONALLICENCE 700 1- Boumans L. National Institute For Public Health and the Environment, Bilthoven, The Netherlands aut NATIONALLICENCE 700 1- Smit A. Plant Research International, Wageningen University and Research Centre, P.O. Box 16, 6700 AA, Wageningen, The Netherlands aut NATIONALLICENCE 700 1- van den Berg M. South African Sugarcane Research Institute (SASRI), Mount Edgecombe, South Africa aut NATIONALLICENCE 773 0- Nutrient Cycling in Agroecosystems Kluwer Academic Publishers 77/2(2007-02-01), 155-167 1385-1314 77:2<155 2007 77 10705 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer