Nutrient Management Strategies for Enhancing Maize Yield and Improving Soil Fertility in the Changbai Mountains—Liaodong Hilly Region: A Meta-Analysis

To further enhance nutrient use efficiency for maize cultivation in the Changbai Mountains—Liaodong Hilly Region and to safeguard both grain production and soil quality, 2441 pairs of data points extracted from 47 publicly published papers were selected for analysis to investigate the effects of different fertilizer types, their application rates, and field management practices on spring maize yield enhancement, crop growth, and soil physicochemical properties. According to the subgroup analysis of the above indicators, the results demonstrated that various fertilization management practices can effectively increase maize yield and soil nutrient content. Specifically, applications of nitrogen fertilizer (39.78%) and top-dressing (34.10%) had the best effect on increasing maize yield. The combination of organic–inorganic application (22.93%) and straw returning (20.46%) had the best effect on increasing soil organic matter. Based on grain yield and its components, crop physiology and soil physicochemical properties, we recommend an optimal nutrient management strategy for this region: an application rate of 180 kg/ha for nitrogen and 70–100 kg/ha for both phosphorus and potassium, and the field management practice of combined application of chemical fertilizers and manure based on full-amount straw returning in the field. This study provides a reference for nutrient management of maize fields in the Changbai Mountains—Liaodong Hilly Region.