Evidence and perception of phosphorus loss risk factors in farmyards

Abstract

Farmyards present potential point sources of phosphorus loss to watercourses, affecting their 16 ecological quality and attainment of environmental goals. Unlike many relatively simple point sources, 17 farmyards are complex sub-systems within the wider agricultural setting, including individual runoff, 18 management and infrastructure factors which influence the risk (likelihood and magnitude) of 19 phosphorus loss. Comparison across these factors is confounded by heterogeneity in farmyard design 20 and management, however, weighting of individual factors will support estimation of the relative 21 riskiness of farmyards. This will allow identification of appropriate mitigation measures and evaluation 22 of cost-benefit ratios. The aim of this study is to evaluate the riskiness of runoff, management, and 23 infrastructure factors on phosphorus loss from farmyards to water, using expert opinion and to 24 evaluate whether those estimates are supported by the literature. A survey of research, advisory and 25 policy stakeholders was conducted (147 respondents) in which individuals rated the importance of 26 individual factors from 0 (having no impact) to 10 (having critical impact) on phosphorus loss from 27 farmyards. The most highly ranked factors were within the infrastructure category, followed by runoff 28 and finally management factors. Factors relating to silage effluent and slurry storage were assigned 29 the greatest risk (≥8.4). Runoff factors were also high risk but may be difficult to mitigate compared 30 to infrastructure. Management factors were rated lower by all stakeholder groups but may offer low 31 cost options to offset more intransigent risks. High consensus was observed between stakeholder 32 groups, with significant differences in risk ratings for only 8 out of 29 individual factors.

Description

Publication history: Accepted - 18 September 2020; Published online - 14 October 2020.

Keywords

farmyard, phosphorus, water quality, point source, risk

Citation

Vero, S.E., Sherry, E. and Doody, D. (2020) ‘Evidence and perception of phosphorus loss risk factors in farmyards’, Environmental Science & Policy. Elsevier BV. doi:10.1016/j.envsci.2020.09.025

DOI

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