Enhancing cropping system productivity and soil properties through cotton/peanut intercropping with optimized row configurations

Background and aims Crop diversified cropping (intercropping) can enhance soil health and crop productivity through integrate resource use, which has been seen as a key strategy for sustainable agriculture and long-term food security. However, different row configurations under intercropping systems can direct affect soil properties and crop productivity, and the studies results are not consistent depend on different experiment site and management practices. Methods To address this, a split-plot field experiment was conducted at two sites (Pingdu and Changyi in Shandong, China) to evaluate row configuration effects on soil properties and crop productivity in the short term. Treatments included monoculture cotton (MC), monoculture peanut (MP), and three intercropping configurations: C2P4 (2 cotton:4 peanut rows), C4P4 (4 cotton:4 peanut rows), and C4P6 (4 cotton:6 peanut rows). Results On average, compared to monoculture, cotton-peanut intercropping systems demonstrated comprehensive improvements, reducing soil bulk density by 4.2–15.5%, increasing soil organic matter (5.2–15.5%), available nitrogen (4.4–14.1%), and phosphorus (4.7–12.0%), while enhancing microbial abundance (bacteria: 14.5–17.4%; fungi: 27.0–35.7%; actinomycetes: 24.7–27.3%). Pearson's correlation analysis showed that humus fractions, microbial abundance and soil nutrient availability are all key determinants of crop yield. These benefits scaled progressively with the peanut-to-cotton row ratio, the C4P6 configuration (4 cotton:6 peanut rows) achieved peak performance, with cotton and peanut yields reaching 4,741.65 kg·ha⁻¹ and 5,484.75 kg·ha⁻¹, respectively, alongside the highest soil quality index (SQI = 1,335), representing an 82.4% improvement over monoculture. Conclusions Cotton-peanut intercropping enhances crop productivity through optimized root-soil interactions that improve soil structure, nutrient availability, and microbial functionality, with the C4P6 configuration demonstrating superior performance by synchronizing interspecific facilitation. This study provides a practical measure for sustainable intensification in the Yellow River Basin of China and semi-arid regions with analogous soil constraints.