Sustainable quinoa production in Morocco: balancing productivity and environmental performance

Increasing quinoa yields through improved nutrient and water management is critical for smallholder farmers in Morocco. However, strategies are needed to minimize tradeoffs between food production and sustainability goals. For two quinoa production scenarios, we evaluated how increasing organic and inorganic nitrogen (N) inputs influenced yields and seven environmental impact categories (global warming potential (GWP), human carcinogenic toxicity, freshwater, marine and terrestrial ecotoxicity, freshwater eutrophication, and fossil resource scarcity). The first scenario included inorganic N fertilizer with deficit irrigation while the second included organic amendments (manure and compost) with full irrigation. Across both scenarios, the primary contributors to GWP were fertilization, irrigation, machinery use, and transportation of organic amendments (9%–75%, 15%–64%, 5%–29%, and 0%–18%, respectively). With inorganic fertilization, quinoa yields increased by 30% above the control at 40 kg N ha −1 , but not at higher N rates. Even at this modest level of N inputs, GWP increased by 69% from 0.99 to 1.68 kg CO 2 eq kg −1 , which corresponded to a 63%–251% increase across other environmental impact categories. With organic amendments, both 10 t ha −1 of compost and 20 t ha −1 of manure achieved the highest quinoa productivity (1,891 and 1,852 kg ha −1 ) with the lowest GWP (1.34 and 1.42 kg CO 2 eq kg −1 ) and a 49%–55% decrease across other environmental impact categories. Here we provide the first integrated assessment of organic and inorganic N management strategies to increase quinoa productivity in Morocco while minimizing environmental impacts.