Investigations on tile drains in clayey regions of the Netherlands
Onderzoek aan drainwater in de kleigebieden van Nederland
26 May 2012, PDF |
131 pages |
Meinardi CR , Eertwegh GAPH van den
RIVM Report 714901007
The investigations of drain water composition in the Netherlands regions with a clayey soil consisted of sampling two or more times the drain water at 18 farms. The emphasis in the determinations was on the analysis of the concentrations of nitrate, ortho-phosphate and total phosphate in drain water, but also other components of the drain water composition were determined. Additionally, the soil was investigated by a simple geohydrological program. Results have been represented in the form of tables, showing the concentrations of the various elements in drain water of separate farms and by figures and descriptions. A significant deviation in the concentrations of nitrate, ortho- and total phosphate was remarked between especially the values for the northern clay district and the other major regions (central and southwestern seaclay districts and the deep polders). Another aim of the investigations was to research possible influences of crop type, the relation between fertilizer and manure levels, a relation with top soil structure and the role of meteorology in the leaching of nutrients from clayey soils.