Ryegrass bioretention for reducing overland-flow and phosphorus export

M Humphreys, K McCleod (North Wyke) & P Haygarth (CWSM, Lancaster)

In the UK, grasslands represent a distinct, spatially dominant sector of land use and represent 72 percent of all land devoted to agriculture (equal to over 13 million ha) (Defra, 2007). From a scientific perspective, UK grasslands present a unique systems-based focus, where biological and environmental systems interact, providing opportunities for collaborations with multi and inter-disciplinary science. For BBSRC, this generates exciting biological challenges; centred on understanding the processes of interaction between plants, livestock derived organic matter, soil biota and their consequential affects on the wider environmental systems, particularly water and atmospheres. This studentship represents the collaboration of two organizations with a strong multidisciplinary track record in grassland science.   The objective of the project is to test the hypothesis that Festuca species, with deeper rooting characteristics and larger more erect foliage compared with Lolium species, can help reduce leakage of phosphorus to the wider environment using the following methods:

1. Construct a conceptual model for the potential bioretention of water and phosphorus by ryegrass
2. Quantification of the relationship between grass phenotype and P transfer to water courses.
3. Identification of species and ideotypes for mitigating P transfer to water courses.
4. Identification of QTLs and markers for ‘barrier traits’ conferring reduced P transfer.