Demonstrating efficacy of on-land management actions to improve water quality: How can we quantify what actions have been done?

We reviewed 91 global publications and proceedings between 1989 and 2019 which assessed the complexities related to recording and reporting sustainable land use actions with a focus on freshwater ecosystems in rural areas in the developed world. We summarised these complexities (i.e., temporal and spatial lag-effects, confidentiality issues, lack of data robustness) and mined the literature about methodologies on how actions can be measured and how to address the challenges with doing this. Our review of literature identified numerous sources describing land management actions, but little information on standardised indicators of location, scale and intensity of the most common actions, making it difficult, if not impossible to determine the scale of actions within a catchment relative to a given water quality monitoring site. We recommend a suite of indicators of land management actions that could be standardised and widely used to improve water quality.