Rotational strip peanut/cereal intercropping systems improve soil quality and crop yields in aeolian sandy soil

Aeolian sandy soil occupied one-fifth of the agricultural land in Northeast China; however, effective strategies to mitigate aeolian sandy soil degradation and enhance crop production remain largely unexplored. Here, a two-year field experiment was conducted on the aeolian sandy soil to evaluate the effects of rotational strip peanut/cereal intercropping systems on soil quality and crop yields. The experiment comprised seven treatments: peanut/corn intercropping with strip widths of 3, 6, and 9 m; peanut/millet intercropping with strip widths of 3, 6, and 9 m; and a peanut monoculture serving as the control. We showed that both peanut/corn and peanut/millet intercropping systems significantly enhanced the nutrient levels including total alkaline- hydrolyzable nitrogen, available phosphorus, available potassium, and organic matter in the rhizosphere soil compared with peanut monoculture. Moreover, the activities of soil enzymes such as catalase, cellulase, urease, and phosphomonoesterase were substantially increased in intercropping treatments. Entropy-weighted TOPSIS analysis indicated that peanut/corn and peanut/millet intercropping with strip width of 6-m treatments achieved optimal performance in regulating soil nutrients, enhancing enzyme activities, and improving land-use efficiency. These two treatments also significantly increased the peanut yield and total output values, reduced total input costs, while optimized economic returns over peanut monoculture. In summary, this study provides scientific evidence that rotational peanut/cereal intercropping systems utilizing a 6-m strip width could be utilized as practical strategies for improving crop production, restoring ecological balance, and ensuring sustainable land management of aeolian sandy soil in Northeast China.