Research progress and prospect on the regulation of intercropping on soil aggregate structure and function

Soil aggregates are the basic units of soil structure and play a crucial role in maintaining soil ecological functions. Intercropping has great potential to promote the formation and stabilization of soil aggregates. However, there is a lack of systematic summary on the mechanisms by which intercropping systems affect the structure and function of soil aggregates. We summarized the rhizosphere processes influencing soil aggregate formation, sorted out the effects and action mechanisms of root structure and morphology, root exudates, rhizosphere microorganisms, soil fauna, and rhizosphere physical processes on soil aggregate formation, and explored the potential processes and mechanisms by which intercropping drives soil aggregate formation by affecting root structure and morphology, root exudates, and rhizosphere microorganisms. Additionally, we reviewed the impacts of intercropping on organic carbon, nutrient content and availability, and microbial community characteristics in soil aggregates with different particle sizes. Finally, we prospected the research directions regarding the regulation of soil aggregate structure and function by intercropping, emphasizing that efforts should be strengthened in the following aspects: quantitative research on the process of soil aggregate formation regulated by intercropping; the effects of intercropping on functional microbial communities at the aggregate level and the corresponding regulatory mechanisms; the spatial and temporal scales of intercropping's impacts on soil aggregate structure; and the development of intercropping technologies and models based on the directional cultivation of macroaggregates.