DEciphering temporal trends and safe operating spaces for river biodiversity within the context of multiple STRESSors (DESTRESS)

Growing human demands for clean freshwater and increasing impacts of climate change put increasing pressure on river ecosystems worldwide. But riverine biodiversity needs for freshwater quality and quantity are not quantified. In other words, we do not currently know exactly how much and how clean freshwater resources should be in order to avoid further biodiversity loss in stream and river ecosystems. DESTRESS is a synthesis project with the overall objective to provide guidance and knowledge to balance freshwater needs between riverine biodiversity and human society. DESTRESS will utilise a highly unique time-series dataset comprising stream invertebrate data for >2,000 sites across 23 European countries; 1968-2020, average 15 years of sampling. This will be used to analyse and identify temporal trends in European stream biodiversity. The temporal biodiversity trends will also be linked to simulated hydrological regimes for a subset of the sites and to existing European data on measured exposure of toxic contaminants to analyse pressure-response relationships. In this context, we will identify biodiversity change points along the existing gradients of hydrological and contaminant stress. The pressure-response relationships will be applied to define 'safe operating spaces' (SOS) for riverine biodiversity in context of their water quality and quantity requirements. Through collaboration and co-creation processes with key stakeholders, the concept of SOS will be applied to relevant case study examples to understand management, end-user, and legislative requirements for the SOS concept. The end-product of DESTRESS will enable evidence-based decision making on freshwater consumption, supply, and treatment to balance water quantity and quality needs between freshwater biodiversity and human society.

Growing human demands for clean freshwater and climate change put increasing pressure on river ecosystems, but riverine biodiversity needs for freshwater quality and quantity are not quantified. DESTRESS is a synthesis project with the overall objective to provide guidance and knowledge to balance freshwater needs between riverine biodiversity and human society. DESTRESS is spearheaded by the Aquatic Synthesis Research Centre (AquaSYNC) and will synthesise and analyse unique and comprehensive time series of European riverine macroinvertebrate monitoring data (>2,000 sites across 23 European countries; 1968-2020, average 15 years of sampling) to identify temporal trends in ecological and biological trait composition, abundance, and common biodiversity metrics. Temporal biodiversity trends will also be linked to simulated hydrological regimes for a subset of the sites and to existing European data on measured contaminant exposure to analyse pressure-response relationships and identify biodiversity change points along the existing gradients of hydrological and contaminant stress. The pressure-response relationships will be applied to define 'safe operating spaces' (SOS) for riverine biodiversity in context of their water quality and quantity requirements. Through co-creation processes with key stakeholders, the concept of SOS will be applied to relevant case study examples to understand management, end-user, and legislative requirements for the SOS concept. These inputs will be embedded into the SOS concept of DESTRESS ensuring that the end-product will become operational, relevant, and will fit to legislative requirements for end-users, managers, and competent authorities. The end-product of DESTRESS will enable evidence-based decision making on freshwater consumption, supply, and treatment to balance water quantity and quality needs between freshwater biodiversity and human society.