Soil is the core resource of agricultural production. It not only provides crops with nutrients and water for growth but also supports multiple ecological functions such as microbial activity and nutrient cycling. This comprehensive capability is termed “soil multifunctionality”. In recent years, soil degradation issues have become increasingly prominent, including erosion, nutrient loss, and declining organic matter. How to enhance soil health through scientific agricultural management measures has become a global priority. As a key practice in sustainable agriculture, crop rotation can improve soil quality by altering soil environments and microbial communities, particularly through rotations between leguminous and gramineous crops—legumes reduce fertilizer dependence via nitrogen fixation by rhizobia. But do different legume crop rotations yield varying effects? Which rotation pattern can systematically enhance soil multifunctionality?
A team led by Prof. Zhenke Zhu from Ningbo University analyzed 261 soil samples across China to systematically compare the impacts of different legume crop rotations on soil properties and microbial communities, revealing the unique advantages of faba bean (Vicia faba) rotation in enhancing soil multifunctionality and its microbial-driven mechanisms. The relevant paper has been published in Frontiers of Agricultural Science and Engineering (DOI: 10.15302/J-FASE-2025604).
The team collected post-harvest soil samples from legume crops across a wide geographic range in China (21.66°–48.02°N, 86.29°–125.26°E), analyzing key indicators such as soil water content, organic carbon, total nitrogen, and total phosphorus, while using high-throughput sequencing to characterize the rhizosphere microbial community structure. Results showed that compared with other legume rotations, faba bean rotation increased soil water content by 29.1%, total carbon, total nitrogen, and total phosphorus by 40.9%, 55.9%, and 18.9% respectively, and organic carbon content by 61.6%. Meanwhile, soil microbial biomass and respiration rate were significantly higher. The “soil multifunctionality index”—a comprehensive assessment of soil fertility, water retention, nutrient cycling, and other functions—scored highest under faba bean rotation.
Further analysis of microbial communities revealed that faba bean rotation significantly increased bacterial richness and diversity, while enriching two key microbial groups: desulfobacterota and Planctomycetota. The former is closely associated with soil nitrogen and phosphorus mineralization, while the latter participates in nitrogen cycling and polysaccharide decomposition. Together, they create favorable conditions for microbial activity and nutrient supply. Microbial co-occurrence network analysis also showed that the microbial network under faba bean rotation was more complex, with stronger “bridge roles” of key microbial groups and more efficient microbial collaboration, further supporting the enhancement of soil functions.
This study compared the soil effects of different legume rotations at the national scale, confirming that the advantages of faba bean rotation in enhancing soil multifunctionality are not accidental but achieved through multiple mechanisms: “improving soil physical-chemical properties—optimizing microbial community structure—enhancing microbial activity”. The study also notes that legume species and regional differences are two primary factors influencing soil properties, providing a scientific basis for selecting adapted legume rotation models in different regions.
DOI: 10.15302/J-FASE-2025604