Abstract: This study explored the impact of intercropping Macrotyloma Uniflorum 'Yazhou’ in litchi orchards on soil microbial community structure, diversity, and soil physicochemical properties. Soil samples from two model litchi orchards intercropping with Macrotyloma Uniflorum 'Yazhou’ and those without Macrotyloma Uniflorum were analyzed for their physicochemical properties and microbes using 16S rRNA amplicon sequencing analysis. After intercropping Macrotyloma Uniflorum 'Yazhou’ in litchi orchards, soil organic matter, total nitrogen, ammonium nitrogen, and available phosphorus content increased by 23.9%, 23.9%, 41.7%, and 60.4%, respectively, indicating that this practice enhances soil nutrient levels. The litchi Macrotyloma Uniflorum 'Yazhou’ intercropping model increases the relative abundance of Bryobacter, which is involved in decomposing organic matter, and Firmicutes, Cyanobacteria, and Bathyarchaeia are unique microbial groups in this model with relative abundances exceeding 1%. Redundancy analysis revealed that pH, total potassium, total nitrogen, and organic matter are the primary physicochemical factors influencing soil microbial community structure at the phylum level in this model. In summary, intercropping Macrotyloma Uniflorum 'Yazhou’ in litchi orchards improves soil nutrient levels, alters soil microbial community structure, and increases the relative abundance of microorganisms that promote organic matter decomposition, thereby optimizing the environmental conditions of litchi orchards.

Key words: Litchi, Intercropping, Macrotyloma uniflorum 'Yazhou’, Soil nutrients, Soil microbial community structure

摘要： 为探究荔枝园间作'崖州’硬皮豆(Macrotyloma uniflorum 'Yazhou’)对土壤微生物群落结构、多样性及土壤理化性质的影响，本研究以荔枝园间作'崖州’硬皮豆和荔枝园未间作两种模式的土壤样品，测定其理化性质，并进行了16S rRNA扩增子测序分析。在荔枝园间作'崖州’皮豆后，土壤的有机质、全氮、铵态氮和有效磷含量分别提高了23.9%，23.9%，41.7%和60.4%，说明荔枝园间作'崖州’硬皮豆能够改善土壤的养分水平。荔枝间作'崖州’硬皮豆模式能够提高分解有机质的Bryobacter的相对丰度，且厚壁菌门(Firmicutes)，蓝菌门(Cyanobacteria)和Bathyarchaeia是该模式下独有的相对丰度大于1%的微生物群类；冗余分析结果表明，pH值、全钾、全氮和有机质是该模式下影响土壤微生物门水平的主要理化因子。综上所述，荔枝园间作'崖州’硬皮豆会提高土壤的养分水平、改变土壤微生物的群落结构、提高促进有机物分解微生物的相对丰度，对荔枝园的环境条件起到一定的优化作用。

关键词: 荔枝, 间作, '崖州’硬皮豆, 土壤养分, 土壤微生物群落结构