Water-Energy-Food-Ecosystem (WEFE) Nexus & Smart Policy Integration

Drought is a climatic phenomenon characterized by a significant decrease in precipitation over an extended period, leading to water scarcity. Globally, this issue affects many regions of the world. In Morocco, drought is particularly concerning as the country is located in an arid and semi-arid region, making it especially vulnerable to this challenge. The primary objective of this study is to characterize climatic drought in the Bouregreg watershed (Morocco) for the period 1973-2023 through the calculation of the The Mean Deviation Index (MDX) and the Standardized Precipitation Index (SPI) at different time scales: 1 month, 6 months, 12 months, and 24 months, for the three studied stations: Lalla Chafia, Ouljet Haboub, and Sidi Mohamed Chrif. The Mean Deviation Index showed that 2010 was the wettest year, while 1983, 1995, and 2007 were the driest. The longest dry periods occurred from 1998 to 2002, and the longest wet periods from 2008 to 2011. In the short term (1 and 6 months), the SPI indicates that the study area experienced moderate drought for 6.9% to 10.3% of the total analyzed time. In the medium term (12 months), 11% to 12.6% of the analyzed time recorded moderate drought. In the long term (24 months), SPI values show that 11% to 15.4% of the total analyzed time recorded moderate drought. Furthermore, the spatialization of the SPI revealed that the southern part of the Bouregreg watershed is more humid, with positive SPI values, while the north is dry, with negative SPI values.

Globally, recovery of nutrients and water from municipal wastewater or biorefinery processing wastewater is crucially important for achieving circular economy and coping with the challenges of water scarcity and fertilizer shortage. However, potential presences of pathogens and chemical contaminants in the reclaimed wastewater raise major concerns for its reuse. Pressure-driven membrane-based separation processes, such as microfiltration (MF), ultrafiltration (UF), allow to obtain superior permeate water, offering an alternative solution to produce liquid fertilizers for plant cultivation; while electrodialysis (ED, an electrical-driven membrane process) is capable to concentrate nutrients and facilitate rapid precipitation of struvite when a sacrificial magnesium (Mg) anode is applied in the ED process). In this presentation, several attempts on membrane-based processes to recover nutrient streams or struvite from primary-treated municipal wastewater and microalgal processing wastewater will be presented, and their feasibility as fertilizers to cultivate plants (such as tomato, lettuce, basil) in soil-based and hydroponic-based systems will be examined based on plant growth and heavy metal uptake. The results revealed that the insignificant difference of plant growth using the MF-treated municipal water and commercial fertilizer solution as irrigation water; the MF-treated microalgal processing wastewater as irrigation water led to slightly less plant growth. Nevertheless, the hazard quotient indexes of heavy metals in the plants were less than 1, indicating negligible human health risk. The Mg-anode ED-based nutrient recovery from municipal wastewater was strongly associated with applied crossflow velocity and current density, and long-term operation of the ED process towards achieving high-purity struvite is on-going.