Intercropping enhances soil multifunctionality by restructuring microbial community and biogeochemical cycles.

Area of Science:

• Agricultural Science
• Soil Science
• Microbiology

Background:

• Intercropping enhances soil ecosystem multifunctionality (SEMF) through microbially-mediated processes, but the driving factors remain unclear.
• Sustainable agriculture practices like intercropping are crucial for improving soil fertility and crop yield.
• Understanding the microbial regulation of SEMF is essential for optimizing agricultural systems.

Purpose of the Study:

• To investigate the factors driving SEMF in intercropping systems under varying nitrogen gradients.
• To assess the impact of intercropping on soil microbial communities and their role in SEMF.
• To establish a framework for optimizing nitrogen fertilization in intercropping systems.

Main Methods:

• Collected soil samples from intercropping and monocropping systems with no, low, and high nitrogen fertilization.
• Analyzed soil microbial communities using amplicon sequencing and functional gene abundance.
• Measured 21 soil ecosystem functions aggregated into six categories and assessed microbial regulation of SEMF.

Main Results:

• Multi-year intercropping significantly enhanced SEMF by 20.3% without nitrogen and 69.6% under low nitrogen, with no effect under high nitrogen.
• Fungal diversity and community composition were identified as primary drivers of SEMF in intercropping.
• Intercropping positively regulated keystone microbial taxa, restructured community composition, improved fungal diversity, and accelerated biogeochemical cycles.

Conclusions:

• Loss of microbial diversity impairs SEMF; intercropping maximizes SEMF, particularly under low-nitrogen conditions.
• Intercropping enhances SEMF by modulating soil microbial communities and accelerating biogeochemical cycles.
• These findings provide a framework for optimized nitrogen fertilization strategies in intercropping systems for sustainable agriculture.