Zhan Xinyi, Shu Yongwei, Guo Liu, Liu Xinyue, Zhao Quan, Li Yuze, Yong Taiwen, Yang Wenyu
College of Agronomy, Sichuan Agricultural University, Chengdu, China.
Sichuan Engineering Research Center for Crop Strip Intercropping System/Key Laboratory of Crop Ecophysiology and Farming System in Southwest, Ministry of Agriculture, Chengdu, China.
Front Microbiol. 2025 Aug 29;16:1658783. doi: 10.3389/fmicb.2025.1658783. eCollection 2025.
Soybean-based intercropping has emerged as a key sustainable agricultural practice, which enhances system productivity and improves soil health. Although numerous studies have investigated soybean yield under intercropping systems, the responses of soil microbial community traits and their associations with yield remain unclear.
Based on 323 observations extracted from 89 peer-reviewed articles, we conducted a meta-analysis to investigate the responses of soil microbial community traits and crop yield to soybean-based intercropping.
Compared to monoculture, our analysis revealed that soybean-based intercropping did not significantly affect soybean yield (effect size = -0.020, 95% CI: -0.105 to 0.065), but significantly changed soil microbial communities. The practice significantly enhanced microbial community α-diversity indices, including Shannon (effect size = 0.036, 95% CI: 0.020 to 0.053), Chao1 (effect size = 0.034, 95% CI: 0.002 to 0.067), and richness (effect size = 0.102, 95% CI: 0.026 to 0.178), while also significantly altered microbial community structure (effect size = 0.741, 95% CI: 0.629 to 0.852). Random forest analysis identified nitrogen fertilization rate as the primary predictor of α-diversity indices. And nitrogen fertilization rate showed a significant negative correlation with Chao1 ( = 0.051, = 0.079) and a marginally significant negative correlation with richness ( = 0.141, = 0.018). Nitrogen fertilizer type significantly affected soil microbial α-diversity, with mixed nitrogen fertilizers demonstrating greater effects on both Chao1 (effect size = 0.111, 95% CI: 0.034 to 0.188) and richness (effect size = 0.192, 95% CI: 0.038 to 0.345) than mineral fertilizers. Intriguingly, while we only found a marginally significant positive correlation between Chao1 and soybean yield ( = 0.131, = 0.082), yield advantages over monoculture emerged within a specific Shannon index range from 0.008 to 0.401. Given the lack of a direct association between nitrogen fertilization rate and soybean yield ( = 0.056, > 0.05), its influence on soybean yield in soybean-based intercropping may mediated by the changes in microbial community diversity.
Collectively, these findings reveal soil microbial responses to soybean-based intercropping and highlight the potential for optimizing microbial communities to enhance soil health and agricultural sustainability in intercropping systems.
基于大豆的间作已成为一种关键的可持续农业实践，可提高系统生产力并改善土壤健康状况。尽管众多研究已调查了间作系统下的大豆产量，但土壤微生物群落特征的响应及其与产量的关联仍不明确。
基于从89篇同行评审文章中提取的323条观测数据，我们进行了一项荟萃分析，以研究土壤微生物群落特征和作物产量对基于大豆的间作的响应。
与单作相比，我们的分析表明基于大豆的间作并未显著影响大豆产量（效应大小 = -0.020，95%置信区间：-0.105至0.065），但显著改变了土壤微生物群落。这种做法显著提高了微生物群落的α多样性指数，包括香农指数（效应大小 = 0.036，95%置信区间：0.020至0.053）、Chao1指数（效应大小 = 0.034，95%置信区间：0.002至0.067）和丰富度（效应大小 = 0.102，95%置信区间：0.026至0.178），同时也显著改变了微生物群落结构（效应大小 = 0.741，95%置信区间：0.629至0.852）。随机森林分析确定氮肥施用量是α多样性指数的主要预测因子。氮肥施用量与Chao1指数呈显著负相关（P = 0.051，R² = 0.079），与丰富度呈边缘显著负相关（P = 0.141，R² = 0.018）。氮肥类型显著影响土壤微生物α多样性，混合氮肥对Chao1指数（效应大小 = 0.111，95%置信区间：0.034至0.188）和丰富度（效应大小 = 0.192，95%置信区间：0.038至0.345）的影响均大于矿物肥料。有趣的是，虽然我们仅发现Chao1指数与大豆产量之间存在边缘显著的正相关（P = 0.131，R² = 0.082），但在香农指数从0.008至0.401的特定范围内，间作相对于单作具有产量优势。鉴于氮肥施用量与大豆产量之间缺乏直接关联（P = 0.056，R > 0.05），其对基于大豆的间作中大豆产量的影响可能是通过微生物群落多样性的变化介导的。
总体而言，这些发现揭示了土壤微生物对基于大豆的间作的响应，并突出了优化微生物群落以增强间作系统中土壤健康和农业可持续性的潜力。
