The study aimed to find the best way to water and fertilize maize crops in northwest China to maximize yield, nitrogen accumulation, and profit while minimizing soil pollution. By testing different irrigation amounts and fertilizer rates, researchers discovered that a balance is needed to achieve high yields without harming the environment. They found that the right combination of water and nutrients can lead to the best results, with certain levels of irrigation and fertilization leading to the highest grain yield and nitrogen accumulation. It was also noted that excessive fertilization can increase soil nitrate levels, but proper irrigation can help mitigate this issue. Ultimately, a specific range of irrigation and fertilization levels was identified as optimal for achieving the best crop outcomes.