Development of a Model for the Implementation of the Circular Economy in Desert Coastal Regions

Abstract

Food production is the main challenge for developing arid regions due to the restricted access to fresh water. This study combines the environmental know-how of two coastal desert regions on the American continent with similar geographical characteristics to propose a general model for a circular economy in stressed environmental conditions. The Atacama Desert, located in Chile, is the driest place on Earth. Due to the lack of rainfall in decades, the possibility of growing food is almost impossible. The Desert of Sonora, in the northwest of Mexico, is known for its extreme aridity and temperatures over 50 °C in summer. Both deserts have continuously growing cities ranging from 400,000 to 900,000 inhabitants, where access to and management of freshwater represents an issue. A circular economy model was developed. Critical parameters for this model considered: the utilisation of solar energy for water desalination and energy production, integrated with hydroponic farming and water dosing with hydrogels for food production; microalgae for biofuels; seaweed for biochemicals; anaerobic digestion for organic waste management and nutrient recovery from wastewater sludge treatment. Regional policies and governance are needed to incentivise the adoption of circular economy models.

Strategies for promoting sustainable aquaculture in arid and semi-arid areas – A review

“…Climate change and desertification are expected to increase salinization and desertification of agricultural lands, according to the World Meteorological Organization. Dry lands are characterized by inhospitable temperatures, inaccessi-ble terrain, and a scarcity of sweet water, which makes them difficult to inhabit (Cabrera-González et al, 2022). It is generally recognized, however, that arid lands have a great deal of potential for development.…”

“…Climate change threatens to cause more droughts in already arid and semi-arid regions of the world and threatens the livelihoods and well-being of hundreds of millions of people. In the near future, it will not be possible to heal global climate change, but we should do all we can to minimize the risks of water scarcity (IPCC, 2022;Cabrera-González et al, 2022). This can be accomplished through the use of efficient irrigation methods, wastewater recycling, collecting drainage and flash flood water, and improving low-cost desalination technologies.…”

Cultivation of the polyextremophile Cyanidioschyzon merolae 10D during summer conditions on the coast of the Red Sea and its adaptation to hypersaline sea water

“…Algae can be cultivated in inexpensive photobioreactors built on non-arable land and directly connected to industrial side-streams to derive value from effluents produced in otherwise overlooked geographical areas such as desert regions or other extreme environments ( Fuentes-Grünewald et al, 2012 ; Vigani, 2020 ; Cabrera-González et al, 2022 ). The implementation of algal bioprocesses in emerging human settlement contexts will further promote algal biomass and bioproduct integration into common use in the bioeconomy ( Cabrera-González et al, 2022 ).…”

“…Algae can be cultivated in inexpensive photobioreactors built on non-arable land and directly connected to industrial side-streams to derive value from effluents produced in otherwise overlooked geographical areas such as desert regions or other extreme environments ( Fuentes-Grünewald et al, 2012 ; Vigani, 2020 ; Cabrera-González et al, 2022 ). The implementation of algal bioprocesses in emerging human settlement contexts will further promote algal biomass and bioproduct integration into common use in the bioeconomy ( Cabrera-González et al, 2022 ). Microalgal bioprocesses are most strategically suited to geographies with high solar irradiation and stable temperatures, having local CO 2 emissions sources, non-arable land, access to sea water, and inexpensive energy sources ( Fuentes-Grünewald et al, 2012 ; Greene et al, 2022 ; Schipper et al, 2022 ).…”

“…It is predicted that in these environments, microalgal biomass production from local inputs can be maximized ( Greene et al, 2022 ). To capture the value of resources in waste-streams, the development and integration of algal bioprocesses can play a role in circular reuse concepts in these environments ( Cabrera-González et al, 2022 ). New target microalgal species with high biotechnological potential, that can tolerate extreme conditions must be identified, characterized, and developed for these contexts.…”