The study looked at how different levels of irrigation and nitrogen fertilizer affected the growth and yield of spring wheat on sandy farmlands in the Heihe River basin. They found that increasing irrigation led to higher water consumption, while nitrogen fertilizer increased above-ground dry matter and grain yield up to a certain point. The best combination for high yield and water use efficiency was low irrigation with 221 kg of nitrogen per hectare. High nitrogen levels above 221 kg per hectare led to more dry matter but also increased drought stress. Overall, the study showed that a specific combination of irrigation and nitrogen levels can maximize wheat yield in this region.