State Key Laboratory of Efficient Production of Forest Resources, Beijing Forestry University, Beijing, 100083, China.
Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
BMC Plant Biol. 2024 Nov 1;24(1):1035. doi: 10.1186/s12870-024-05648-7.
The interaction between soil characteristics and microbial communities is crucial for poplar growth under different planting densities. Yet, little is understood about their relationships and how they respond to primary environmental drivers across varying planting densities.
In this study, we investigated poplar growth metrics, soil characteristics, and community assembly of soil bacterial and fungal communities in four poplar genotypes (M1316, BT17, S86, and B331) planted at low, medium, and high densities. Our findings reveal that planting density significantly influenced poplar growth, soil nutrients, and microbial communities (P < 0.05). Lower and medium planting densities supported superior poplar growth, higher soil nutrient levels, increased microbial diversity, and more stable microbial co-occurrence networks. The assembly of bacterial communities in plantation soils was predominantly deterministic (βNTI < -2), while fungal communities showed more stochastic assembly patterns (-2 < βNTI < 2). Soil available phosphorus (AP) and potassium (AK) emerged as pivotal factors shaping microbial communities and influencing bacterial and fungal community assembly. Elevated AP levels promoted the recruitment of beneficial bacteria such as Bacillus and Streptomyces, known for their phosphate-solubilizing abilities. This facilitated positive feedback regulation of soil AP, forming beneficial loops in soils with lower and medium planting densities.
Our study underscores the critical role of planting density in shaping soil microbial communities and their interaction with poplar growth. This research carries significant implications for enhancing forest management practices by integrating microbiological factors to bolster forest resilience and productivity.
土壤特性和微生物群落之间的相互作用对于不同种植密度下的杨树生长至关重要。然而，对于它们之间的关系以及它们如何响应不同种植密度下的主要环境驱动因素，我们知之甚少。
在这项研究中，我们调查了四个杨树基因型（M1316、BT17、S86 和 B331）在低、中、高种植密度下的杨树生长指标、土壤特性和土壤细菌和真菌群落的群落组装。我们的研究结果表明，种植密度显著影响杨树生长、土壤养分和微生物群落（P<0.05）。较低和中等种植密度支持杨树生长、更高的土壤养分水平、增加的微生物多样性和更稳定的微生物共生网络。种植土壤中细菌群落的组装主要是确定性的（βNTI<-2），而真菌群落表现出更多的随机组装模式（-2<βNTI<2）。土壤有效磷（AP）和钾（AK）是塑造微生物群落和影响细菌和真菌群落组装的关键因素。AP 水平的升高促进了有益细菌的招募，如芽孢杆菌和链霉菌，它们以解磷能力而闻名。这促进了土壤 AP 的正反馈调节，在低和中种植密度的土壤中形成有益的循环。
我们的研究强调了种植密度在塑造土壤微生物群落及其与杨树生长相互作用方面的关键作用。本研究对于通过整合微生物学因素来增强森林管理实践、提高森林的恢复力和生产力具有重要意义。
