Drivers and thresholds of change for European wetlands

D1.2 will assess the direct and indirect drivers of change in wetland functioning and whether changes or reversals in some drivers will contribute to sustained restoration. Drivers include, for example, climate, water and land management, as well as community interactions (WP2), policy, and governance (WP3). The Task will assess the interactions between these drivers and their role in pushing wetlands across thresholds of change. In many wetland systems there are feedback loops and non-linear interactions between drivers of change and wetland function, which may result in catastrophic shifts between alternative stable states. If a wetland crosses a threshold or tipping point, then the reversal of a driver (e.g. reduced phosphorus input) may not simply result in the wetland functions returning to their original state. Therefore, in addition to changing the driving forces, other actions may be required to restore wetland functions. Hence, understanding the different drivers, their interactions with each other, how they influence wetland functioning, and identifying critical thresholds, is essential for defining the ‘Safe Operating Space’ for wetlands (Task 1.3). We will synthesise the scientific understanding of drivers of wetland change across disciplines and subject it to an external on-line review by wetland researchers and wetland practitioners (~ 200 people). Opening the evidence to external evaluation, it will support wider project objectives of co-creation (WP5) and dissemination (WP7) with regard to the understanding of the interactions between on-site drivers of change and off-site stressors) Drivers may be direct (e.g. water level) or indirect (e.g. water management and regional upstream abstraction policy), local (e.g. livestock grazing pressure) or regional (e.g. water abstraction elsewhere in the watershed/aquifer). We will also be able to extract information specifically about our Knowledge and Action Sites from this expert survey but will include a larger sampling of experts from other locations with similar wetlands to allow for wider applicability to the assessment for future upscaling.We will use the data and feedback to derive quantifiable functional relationships of the response of wetlands to drivers of change, including the indicators outlined by Task 1.1 for the Knowledge and Action sites. For example, we will quantify the upstream flow stressors or nutrient loading drivers that result in cumulative effects. We will also analyse the evidence for whether reversing/reducing different drivers of change in a recovery of wetland functioning or not.