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

Abstract

Despite several decades of encouraging land management actions to improve water quality on rural land, we are still struggling to accurately quantify what management actions have been implemented, where these actions have been used and the intensity of implementation. This is largely because standardised approaches to recording and reporting of land management actions have not been established, resulting in a lack of robust information that can be used to determine the effectiveness and longevity of these actions at a catchment or larger scale. Better information on the effectiveness of different land management actions will provide land managers with more certainty that their investments in land management actions will make a difference. We reviewed a total of 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 then 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, how to address the challenges with doing this and recommended a suite of indicators of land management actions that could be standardised and widely used to improve water quality. 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. Some common actions are measured using a wide variety of incompatible approaches (e.g., riparian management is often indicated by length of fencing, width of vegetated buffer strips, proportion of the catchment with stock exclusion), whereas other indicators of land management action are at such a high level (e.g., costs) that they do not provide information on the actions used. The scale/intensity of land management efforts is often not reported spatially with information typically restricted to small scales such as single point location information, making it difficult, if not impossible to determine the scale of actions within a catchment relative to a given water quality monitoring site.