Nitrogen (N) fertilizers are one of the most expensive inputs in agricultural settings. Additionally, the loss of N increases costs, contributes to soil acidification, and causes off-site pollution of the air, groundwater and waterways. This study reviews current knowledge about technologies for N fertilization with potential to increase N use efficiency and reduce its negative effects on the environment. Classic inorganic sources such as urea and ammonium sulfate are the major sources utilized, while controlled N release fertilizers have not been significantly adopted for cereals and oil crops. Microorganisms, with the exception of Rhizobium sp. in soybeans, are also not widely used nowadays (e.g., plant growth-promoting bacteria and cynobacteria). The interest in implementing new N fertilization knowledge is stimulating the development of sensors to diagnose the N status and decision support systems for integrating several variables to optimize sources, rates and methods of application. Among potential new technologies we identified the incipient development of nanofertilizers, nutrient formulations to coat seeds, and recycled nutrients. Furthermore, increasing concern about the environmental consequences of N may facilitate the implementation of innovations outside the farm such as more effective regulations to guide N fertilization and methods to manufacture N fertilizers that are more energy-efficient and less CO₂ equivalent emitting.

Physical and environmental vulnerability analysis conducted for the Illangama watershed located in Ecuador's Andean highlands, shows deteriorated soil quality and declining crop productivity. These problems are caused by soil erosion in steep slopes and inappropriate soil management practices. Research projects conducted from 2011 to 2014 adopted and examined the feasibility of conservation agriculture practices for potato (Solanum tuberosum L.), oat (Avena sativa L.) and vetch (Vicia sativa L.), barley (Hordeum vulgare L.), bean (Vicia faba L.), and a mixture of pastures (annual ryegrass [Lolium multiflorum Lam.], perennial ryegrass [L. perenne L.], orchardgrass [Dactylis glomerata L.], white clover[Trifolium repens L.], and red clover [T. pratense L.]). The practices included surface water deviation ditches, reduced tillage, residue retention, and application of N, all within an improved rotation. The study examined crop yields and economic returns in an effort to identify the best practices. Results indicate that crop productivity and net (of cost of production) benefits of the system were increased as much as 25 and 24%, respectively, using a feasible conservation agriculture system compared to conventional practices. This study shows that conservation agriculture increases yields and saves on production costs due to less tillage. We also found that N fertilization with these conservation agriculture practices increases yields and net returns. This study concludes that conservation agriculture practices are good alternatives for these high‐altitude Andean soils. The practices should be promoted among Andean producers to increase the productivity and sustainability of their potato–grain–pasture systems.Core Ideas The Andean region of Ecuador is critical for the country's food security. Cultivation of high‐slope mountainous agriculture is accelerating erosion. Conservation agriculture is an attractive management alternative. Implementation of reduced tillage could contribute to higher net income for farmers. These practices could benefit nearly 200,000 Ecuadorean farms.