Li Yuanyuan, Zhang Qiong, Zhu Lixia, Yang Jing, Wei Jingjing, Li Yunhe, Chen Xiaohuang
Provincial Key Laboratory of Landscape Plants with Fujian and Taiwan Characteristics, Minnan Normal University, Zhangzhou, 363000, China.
Fujian Province University Key Laboratory of Pollution Monitoring and Control, Minnan Normal University, Zhangzhou, 36300, China.
Environ Microbiome. 2025 May 24;20(1):57. doi: 10.1186/s40793-025-00721-6.
The application of oyster shell has recently been used to increase soil pH in Southern China. However, little is known about causal shifts in the rhizosphere microbial community of pomelo trees, especially in orchards that have experienced natural accumulation of heavy metals over many years due to continuous fertilization and soil acidification. This study evaluated the effects of oyster shell powder applied for 1 year (T1), 2 years (T2) and 3 years (T3), alongside a control group with no soil amendments (Control; CK), on soil acidification and microbial diversity. Our findings demonstrated that the application of oyster shell significantly increased soil pH and reduced the concentrations of heavy metals such as thallium (Tl), chromium (Cr), and manganese (Mn). Illumina sequencing-based community analysis revealed that oyster shell application significantly increased the alpha diversity indices of both bacterial and fungal communities and influenced their distribution in the soil. Notably, all oyster shell-treated groups (T1-T3) showed significantly higher relative abundances of beneficial microbes (e.g., Nitrolancea, Vicinamibacterales) and those involved in carbohydrate degradation and nitrogen fixation compared to the control. Conversely, the relative abundances of Acidibacter and Chujaibacter (associated with heavy metal degradation and soil-borne diseases), Trichoderma and Acremonium (plant-beneficial fungi), as well as functionally annotated groups linked to nitrogen assimilation and pathotrophic modes (predicted via FUNGuild analysis), decreased significantly. Our results suggest that the application of oyster shell powder amendments contributes to improved soil properties and microbial environments; however, the effects on soil nitrogen cycling and fungal function are complex, warranting further research.
近年来，在中国南方，牡蛎壳已被用于提高土壤pH值。然而，对于柚树根际微生物群落的因果变化知之甚少，特别是在那些由于长期施肥和土壤酸化而经历了多年重金属自然积累的果园中。本研究评估了施用1年（T1）、2年（T2）和3年（T3）的牡蛎壳粉以及未进行土壤改良的对照组（对照；CK）对土壤酸化和微生物多样性的影响。我们的研究结果表明，施用牡蛎壳显著提高了土壤pH值，并降低了铊（Tl）、铬（Cr）和锰（Mn）等重金属的浓度。基于Illumina测序的群落分析表明，施用牡蛎壳显著提高了细菌和真菌群落的α多样性指数，并影响了它们在土壤中的分布。值得注意的是，与对照组相比，所有牡蛎壳处理组（T1-T3）中有益微生物（如硝化刺菌属、邻氨基杆菌目）以及参与碳水化合物降解和固氮的微生物的相对丰度均显著更高。相反，与重金属降解和土传病害相关的酸杆菌属和楚氏杆菌属、木霉属和枝顶孢属（植物有益真菌）以及与氮同化和致病营养模式相关的功能注释组（通过FUNGuild分析预测）的相对丰度显著降低。我们的结果表明，施用牡蛎壳粉改良剂有助于改善土壤性质和微生物环境；然而，对土壤氮循环和真菌功能的影响较为复杂，值得进一步研究。
