Influence of Hydrological Processes on Phosphate Leaching in Tile Drained Sandy Soils

Influence of Hydrological Processes on Phosphate Leaching in Tile Drained Sandy Soils: A Case Study in the Bollenstreek

Tiesma, Menno (TU Delft Civil Engineering and Geosciences)

Bogaard, T.A. (mentor)
Barcala Paolillo, Victoria (graduation committee)
van Breukelen, B.M. (graduation committee)
Foppen, Jan Willem (graduation committee)
Rozemeijer, Joachim (graduation committee)

Delft University of Technology

Civil Engineering

2022-06-05

Leaching of phosphorus (P) from agricultural land is an important source of eutrophication in the Bollenstreek in the Netherlands. This is because floriculture has led to high P concentrations in the sandy soils with low organic carbon content, which are characterised by a low retention capacity for P. In this study, P concentrations in groundwater from three plots in the Bollensteek were found to exceed the water framework directive (WFD) by a factor of 40. The case study on a single plot showed a phosphate load of 5.5 kg/ha/year leached through the tile drains, which is an order of magnitude higher than fields outside the Bollensteek. To understand where phosphate comes from and how hydrological processes influence leaching, hydraulic and chemical measurements of soil, groundwater and tile drain outflow were taken in a field with regulated tile drainage, and two hydrological models were created to simulate wet winter and dry summer conditions. The results showed the flow paths from this plot under wet and dry conditions and illustrated how hydrological processes can influence phosphate leaching through the soil and tile drains.

phosphate
leaching
Bollenstreek
Case study
Floriculture
Hydrological processes
Field scale

http://resolver.tudelft.nl/uuid:8a2f51b8-36f6-4377-9d24-503c36b6b226

2022-06-14

Student theses

master thesis

© 2022 Menno Tiesma