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The excessive application of nitrogen (N) has caused a series of environmental problems. Brown earth (BE) is one of the main soil types in China, and the specific soil-forming conditions make it high risk of nutrient leaching. Determining the soil fertility of BE and optimal N application rates for main crops' production is important to reduce nitrogen leaching. Based on China's second national soil survey, the basic fertility level of BE was defined, and the effects of four N management methods [one-time base fertilizer (BF), topdressing (TF), combined organic fertilizer (OF) and controlled-release fertilizer (CF)] on maize and wheat yield and N efficiency were analysed. The study found that except for lower phosphorus content (level 4), the soil fertility of BE was at a moderate level (level 3). Compared with no N application, these four N management methods significantly increased the maize and wheat yield and showed the trend of OF > CF > TF > BF; TF, CF and OF significantly increased the N efficiency comparison with BF. The optimal N application rates for wheat and maize were 129-174 kg ha −1 and 170-235 kg ha −1 , respectively, when considering the win-win of yield and N efficiency. N fertilizer reduction in BE needs to be further strengthened, and the specific N application rates to achieve profit maximization should be adjusted depending on environmental factors.

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