Phosphorus and nitrogen losses from temperate permanent grassland on clay-loam soil after the installation of artificial mole and gravel mole drainage

• Published in: The Science of the total environment 2019-04, Vol.659, p.1428-1436
• Main Authors: Valbuena-Parralejo, N., Fenton, O., Tuohy, P., Williams, M., Lanigan, G.J., Humphreys, J.
• Format: Article
• Language: English
• Subjects: Ammonium; Mole and gravel mole drainage; Nitrate; Pathways interactions; Phosphorus
• ISSN: 0048-9697; 1879-1026
• DOI: 10.1016/j.scitotenv.2018.12.173

Mole (M) and gravel-mole (GM) drainage systems improve the permeability of soils with high clay contents. They collect and carry away infiltrating water during episodic rainfall events. Characterisation of nutrient fluxes (concentration and flows) in overland flow (OF) and in mole drain flow (MF) across sequential rainfall events is important for environmental assessment of such drainage systems. The objective of this study is to assess the impact of drainage systems on soil nutrient losses. Three treatments were imposed on grazed permanent grassland on a clay loam soil in Ireland (52°30′N, 08°12′W) slope 1.48%: undrained control (C), mole drainage (M) and gravel mole drainage (GM). Plots (100 m × 15 m) were arranged in a randomized complete block design with four replicated blocks. Nitrogen (N) and phosphorus (P) concentrations in OF, MF and groundwater (GW) were measured from each plot over 15 consecutive rainfall events. The results showed that M and GM (P