Abstract:

The study of changes in soil bacterial communities and diversity characteristics in photovoltaic power stations in karst desertification areas, as well as their key regulatory factors, is of great significance for assessing the impact of photovoltaic station construction on the ecological environment. In this study, three different photovoltaic arrays (high, medium, and low) within the Shilin photovoltaic demonstration area in Yunnan, as well as a control area without photovoltaic arrays (outside the panel), were selected. High-throughput sequencing was used to analyze the soil bacteria and their responses to different photovoltaic array treatments and environmental factors. The results showed that environmental factors, soil bacterial community composition, and diversity responded positively to changes in photovoltaic array height. Soil moisture content, pH, total potassium, and plant diversity increased significantly with increasing array height, whereas soil organic matter content and density decreased significantly. The increase in photovoltaic array height significantly promoted the relative abundance of Proteobacteria and Actinobacteria, but reduced the relative abundance of Acidobacteria. Soil bacterial diversity (α and β diversity) increased significantly with photovoltaic array height, reaching its maximum in the high-array region. RDA and random forest models indicated that soil total potassium and pH significantly promoted bacterial α-diversity, with notable effects on the relative abundance of Actinobacteria and Acidobacteria, respectively. Soil moisture content significantly altered the bacterial β-diversity. The results indicated that the installation of photovoltaic panels primarily influenced the dominant bacterial communities and diversity changes by altering the soil total potassium content, moisture, and pH levels. This study provides a reference for assessing the ecological impacts of photovoltaic power station construction in karst desertification areas.

Key words: rocky desertification, soil, bacterial community, diversity, photovoltaic array

摘要：

研究石漠化地区光伏电站土壤细菌群落和多样性的变化特征及其关键调控因子，对于评估光伏电站建设对生态环境的影响具有重要意义。选取云南石林光伏示范区内3种不同高度的光伏阵列（高板、中板、低板）以及未架设光伏阵列的对照区域（板外）为研究对象，采用高通量测序技术对土壤细菌进行测序，分析其在不同光伏阵列处理下的变化及对环境因子的响应。结果显示，环境因子、土壤细菌群落组成及多样性会积极响应光伏阵列高度的变化，其中，土壤含水量、pH值、全钾含量、植物多样性沿光伏阵列高度呈显著的增加趋势，而土壤有机质含量与密度呈显著的减少变化；光伏阵列高度的增加显著促进了变形菌门、放线菌门的相对丰度，但会降低酸杆菌的相对丰度。土壤细菌多样性（α和β多样性）沿光伏阵列高度呈显著的增加变化，在高板光伏阵列区域达到最大值；RDA分析和随机森林模型表明，土壤全钾和pH能够显著促进细菌的α多样性，且分别对放线菌门、酸杆菌门的相对丰度具有显著的促进作用，而含水量会显著地改变细菌的β多样性。结果表明，光伏阵列的架设主要通过改变土壤全钾含量、含水量和pH值来影响优势细菌群落和多样性变化。该研究可为石漠化地区光伏电站建设对生态环境影响的评估提供参考。

关键词: 石漠化, 土壤, 细菌群落, 多样性, 光伏阵列