Systems Modeling of the Water-Energy-Food-Ecosystems Nexus: Insights from a Region Facing Structural Water Scarcity in Southern Spain.

The complex relationship between water, energy, food, and ecological systems, known as the WEFE nexus, has emerged as a major topic in the debate about sustainable economic development and resource management. This subject is of special interest in Mediterranean coastal areas as rapid economic expansion driven by population growth, higher influx of tourists, and intensification of agriculture is leading to structural water scarcity conditions. However, addressing the diverse range of issues associated with the nexus is a difficult task due to the existence of intricate interconnections, interdependencies, and nonlinearities within and across its various components.

Challenges for Circular Economy under the EU 2020/741 Wastewater Reuse Regulation.

Wastewater reuse is seen as an opportunity to support a circular economy and optimize water resources. However, the use of wastewater is limited by the need for the proper protection of health and the environment and demands a certain minimum quality of treated reclaimed water. The objective of this work is to evaluate the opportunities both for the agents in the water treatment chain (from municipalities to farmers) and for technology providers under the recently approved Regulation EU-2020/741.