The role of the near-surface pathways in the delivery of flow and nutrients to streams in Irish catchments

Abstract

Management of pollution from diffuse agricultural and small point sources remains a significant challenge worldwide. Understanding and quantifying the contributions of flow and nutrients, through each hydro(geo)logical pathway, to the receptor of interest, is an important part of identifying the highest-risk, critical source areas (CSAs). The aim of this research was to develop an improved conceptual understanding of the near-surface pathways in the delivery of flow and nutrients to streams. The near-surface pathways included interflow, artificial drainage and flow in the transition zone, i.e. the weathered zone between the top of the bedrock and the overlying subsoils.