Water-related processes: IPBES Nexus assessment Options for delivering sustainable approaches to water

The recently approved and published IPBES Nexus Assessment, focuses on the interactions and interlinkages between biodiversity, water, food, health and climate. This assessment, requested by member states signatory to IPBES, defines nexus approaches, scenarios for nexus interactions and response options to each of the nexus elements with particular focus on cascading effects beyond a single nexus element. Within this context, we developed and examined the response options for water and their percolation to the other nexus elements. In this presentation, we will show (i) our process to identify the water response options which included multiple knowledge systems, (ii) their evaluation through assessing enablers and barriers, feasibility, context and scale and governance, and (iii) the robustness of our knowledge on the effectiveness of these response options to deliver on water quantity and quality. Currently, ~80% of humanity’s freshwater demand is used to meet food production, 75% of the global population in 2005 is dependent on forest for accessible freshwater, and at least 50 diseases are attributable to poor water supply, quality and sanitation. We find that the 15 response options that we examined cut across more than two nexus elements, yet we found no response option that would deliver benefits to all nexus elements concurrently. Particularly, stronger or more robust trade-offs emerge when water, biodiversity and food systems are considered. Future scenarios show that a nature positive nexus will concurrently deliver on all nexus elements, and for water specifically, the strongest impacts emerge if food systems are prioritized as well as nature overexploitation.